NASA SP-7037 (62) -I s ~ »• N» > n | to c « -^ o' s. JT; S. 5' 397 A75-38144 works dedicated to the sixtieth birthday of academician Vladimir Nikolaevich Chelomei Moscow, Izdatel'stvo VINITI, 1974, p 97-102 8 refs In Russian Weis-Fogh (1973) has proposed a special mechanism to explain the superior performance of the chalcid wasp Eucarsia formosa The buildup of the lift coefficient by other hovering insects is delayed by the Wagner effect, i e , the time required for vorticity shedding from the trailing edge to generate the necessary circulation around the wing Encarsia formosa, however, eliminates the Wagner effect in building up maximum lift by preceding each beat of the wings by a special movement, the 'clap and fling' In the present paper, the Weis-Fogh mechanism of lift generation is analyzed on the basis of unsteady-state aerodynamics for plane flow It is shown that, in addition to the elimination of the Wagner effect, flow separation effects are an important factor in the Weis-Fogh mechanism V P A75-38340 National Symposium on Helicopter Aero- dynamic Efficiency, Hartford, Conn , March 6, 7,1975, Proceedings Symposium sponsored by the American Helicopter Society New York, American Helicopter Society, Inc , 1975 224 p S20 The proceedings deal with the influence of rotor aerodynamic design on performance and noise, advanced airfoil developments, and parasite drag reduction Among the maior topics discussed are the identification of factors influencing the hovering performance of helicopter rotors, the use of antitorque devices other than tail rotors, the improvement of performance by tip air mass injection, evaluation of airfoil sections for helicopter rotor applications, the effects of parasite drag on rotor performance and dynamic response, a cost benefit evaluation of helicopter parasite drag reductions, and a tunnel spanning airfoil testing technique s D A75-38144 # Investigation of self-oscillations of an auto- pilot mount (Issledovame avtokolebann stenda s avtopilotom) N V Butenin, P A Zemskov, and V S Metrikm (Gor'kovskn Gosudarstvennyi Universitet, Gorki, USSR) In Selected problems in applied mechanics Collection of works dedicated to the sixtieth birthday of academician Vladimir Nikolaevich Chelomei (A75- 3812618-39) Moscow, Izdatel'stvo VINITI, 1974, p 179-186 8 refs In Russian The existence and uniqueness of stable asymmetric self- oscillatory motion without slippage in an autopilot mount are proven by the method of point-to-point mapping It is shown that stable symmetric modes with slippage do not exist Quantitative characteristics of the motion are analyzed together with the separation of the parameter plane in the region of stability F G M A75-38261 f,' The cost-effectiveness of mertial navigation for civil aircraft A A Edwards Journal of Navigation, vol 28, July 1975, p 274 282, Discussion, p 282 285 The article compares the 1969 predictions and the 1974 actual cost and accuracy of mertial navigation The realized capital outlay and maintenance expenditure were greater than predicted but these were offset in 1974/5 by higher system utilization The difference between predicted and realized expenditure did not exceed 3 percent The earlier progress and temporary setbacks, which caused significant improvements and beneficial design changes in INS are explained Future INS developments include a grid point storage system for magnetic variation, navigational accuracy improvement methods and new sensor techniques Strap down techniques are seen by the airlines as an extremely promising development and would be acceptable both as a vertical reference and as a source of navigational data M G A75-38262 H Future trends in flight control systems G H Hunt (Royal Aircraft Establishment, Farnborough, Hants, England) (Royal Institute of Navigation and Institution of Electronic and Radio Engineers, Joint Meeting on Advances in Airborne Equipment for Navigation and Freight Control, London, England, Jan 15, 19751 Journal of Navigation, vol 28, July 1975, p 286 299 The problems of reliability, integrity, and failure in flight control systems are followed by separate discussions of the outer- loop system, which can fail but being of limited authority can be switched out, and the inner loop system which must never completely fail, otherwise the control of the whole aircraft is lost The relationship between system failure rate and complexity for systems principally comprised of processors, rather than sensors and actuators is shown The fly by wire control system, its advantages, and the disadvantages resulting from the presence of the mechanical standby linkage are discussed The advantages that digital computers and data transmission possess for the fly-by wire applications are summarized Current FBW/CCV (control configured vehicle) programs represent a large and important trend in aircraft technology, in which the control system is assuming an importance in the design cycle equal to that of the airframe and engines M G A75-38341 # Uniform downwash with rotors having a finite number of blades F D Harris and M A McVeigh (Boeing Vertol Co , Philadelphia, Pa ) In National Symposium on Helicopter Aerodynamic Efficiency, Hartford, Conn, Maich 6, 7, 1975, Proceedings New York, American Helicopter Society, Inc , 1975, p 1 1-1 26 20 refs The classical blade element momentum theory for an infinite bladed rotor is reexammed to show that the historically defined optimum rotor is not correct for a practical rotor with a finite number of blades Fixed-wing aerodynamic theory is used to demonstrate that the loading on a single blade is better represented by treating the rotor blade as a wing in a linearly varying spanwise velocity field An approximation for the velocity induced by a rolled-up trailed tip vortex is suggested Realistic goals for maximum hovering performance efficiency of rotors with a finite number of blades and uniform downwash are discussed S D A75 38342 /• A second approximation to the induced drag of a rotor in forward flight R W Prouty (Summa Corp , Hughes Helicopters Div , Culver City, Calif ) In National Symposium on Helicopter Aerodynamic Efficiency, Hartford, Conn , March 6, 7, 1975, Proceedings New York, American Heli- copter Society, Inc , 1975, p 2 1 2 4 The method of determining the induced drag of a wing from the distribution of circulation in its wake has been adapted for an infinite bladed helicopter rotor Using this method, a 'rotor induced efficiency factor' can be determined which will result in computing more realistic induced drag values than the conventional momentum method T.ie factor is shown to be a function of rotor geometry and flight conditions and is plotted for several combinations of these parameters (Author) A75-38343 H Trimming dual control rotors for optimum performance D W Robinson, Jr and F K Dunn (Kaman Aerospace Corp, Bloomfield, Conn) In National Symposium on Helicopter Aerodynamic Efficiency, Hartford, Conn , March 6, 7, 1975, Proceedings New York, American Helicopter Society, Inc , 1975, p 31-313 5 refs Certain advanced rotor concepts, in addition to the conventional collective and first harmonic control inputs, feature a secondary control input to alter the loading distribution, thereby improving performance Trimming such a rotor requires selecting primary and secondary control input settings to achieve specified trim forces at the most favorable trade off of performance parameters Trade off optimization using typical aeroelastic rotor analyses directly is prohibitively expensive The paper discusses and illustrates an indirect approach using response surface analysis Results of a limited number of aeroelastic analysis cases are used to develop a simple mathematical model of rotor responses of interest Optimization is performed with the simple model, and the final selection of controls confirmed by the main rotor analysis program (Author) 398 A75-38350 A75-38344 # Summary of antitorque devices other than tail rotors F Ra i t ch fUS Army, Army Mobility Research and Develop- ment Laboratory, Fort Eustis, Va ) In National Symposium on Helicopter Aerodynamic Efficiency, Hartford, Conn , March 6, 7, 1975, Proceedings New York, American Helicopter Society, Inc. 1975, p 41-49 6 refs Past and present efforts in replacing tail rotors on single-mam- rotor helicopters for reasons of safety, vulnerability, noise, ef ficiency, and high-speed dynamics are reviewed Fan in-fin and fan-m-fuselage designs are discussed It is shown that modifying any existing helicopter with a different antitorque and yaw control device will cause serious weight and center-of-gravity problems, and that alternatives to the tail rotor are likely to best serve their purpose on small-to-medium-seized vehicles with indifferent yaw stability contribution, especially near zero thrust Most helicopters already have insufficient yaw damping, which will be aggravated by tail rotor elimination S D A75-38345 * # Summary of results indicating the beneficial effects of rotor vortex modification R P White, Jr, J C Balcerak (Systems Research Laboratories, Inc, Rochester, N Y ) , and R J Pegg (NASA, Langley Research Center, Hampton, Va ) In National Symposium on Helicopter Aerodynamic Efficiency, Hartford, Conn , March 6, 7, 1975, Proceedings New York, American Helicopter Society, Inc , 1975, p 5 1 5 1 5 15 refs The possibility of reducing blade-slap noise and high-frequency air loads and of increasing performance by tip air mass injection (TAMI) is investigated The discussion is limited to two types of TAMI chordwise injection with air injected at the blade tip in a chordwise direction and spanwise injection with air injected in a spanwise direction Experimental and analytical results indicate that a properly designed TAMI system can restructure the near field characteristics of a concentrated vortex that trails off the tip of a lifting surface, that the tip vortex is spread by the application of chordwise TAMI, that mixing exists between the injected air mass and the vortex flow which enhances vortex decay, that the net power requirements to implement the system on operational hehcopteis are within acceptable levels, that maximum drop of noise level reduc tions of about 25 dB can be achieved, and that a decrease in the drag induced by the tip vortex in a spanwise TAMI system can be obtained by restructuring the vortex as it forms along the airfoil chord and by moving the vortex farther outboard of the tip S D A75-38346 K The supersonic rotor J P Jones (Westland Helicopters, Ltd , Yeovil, Somerset, England) In National Symposium on Helicopter Aerodynamic Efficiency, Hartford, Conn , March 6, 7, 1975, Proceedings New York, American Helicopter Society, Inc , 1975, p 6 1 6 8 9 refs An account is given of some theoretical studies of the operation of a helicopter rotor at tip speeds which are about twice the speed of sound It is shown that the blade loadings of a supersonic rotor operating near its optimum are about three times those of a conventional rotor One horse power generates two to three pounds of lift The power required does not increase with altitude and in forward flight the supersonic l i f t does not vary significantly as the blade rotates Theoretical estimates of the noise are compared with experimental evidence and it is shown that the noise level will remain sensibly constant beyond a Mach number at the tip of about 1 1 There are shock-free zones above and below the rotor The implications of these features for helicopter aerodynamic design are discussed (Author) A75-38347 fj Acoustic effects of rotor-wake interaction during low-power descent B D Charles (Bell Helicopter Co , Fort Worth, Tex ) In National Symposium on Helicopter Aerodynamic Efficiency, Hartford, Conn , March 6, 7, 1975, Proceedings New York, American Helicopter Society, Inc, 1975, p 7 1 7 8 6 refs Helicopter blade vortex interaction noise has been measured in partial-power descent using a microphone array mounted external to the vehicle The array was designed to permit spatial location of dominant slap noise sources while mapping intensity levels with forward speed and descent rate Vortex interactions were predicted using a free-wake aerodynamic analysis, and show good trend correlation with noise intensity variations with descent rate How ever, the predicted intersection azimuth positions yield only fair agreement with position data Vortex interaction aerodynamics are modeled simply by two-dimensional, quasi static theory and indicate that shock formation and stall may be responsible for intense slap noise (Author) A75-38348 # A state-of-the-art survey of two-dimensional airfoil data R W Prouty (Summa Corp , Hughes Helicopters Div , Culver City, Calif ) In National Symposium on Helicopter Aero- dynamic Efficiency, Hartford, Conn , March 6, 7, 1975, Proceedings New York, American Helicopter Society, Inc, 1975, p 8 1 8 1 2 32 refs A survey of existing two dimensional airfoil data has been made in order to provide the basis for developing new airfoils with particular characteristics or for comparing an existing airfoil with the current state-of the art It is shown that the most significant aerodynamic characteristics are related to a few key physical parameters It is also shown that test differences in Reynolds numbers can seriously distort comparisons of one airfoil with another (Author) A75-38349 " " An analytical and experimental evaluation of airfoil sections for helicopter rotor application G J Bmgham and K W Noonan (U S Army, Air Mobility Research and Development Laboratory, NASA, Langley Research Center, Airfoil Research Section, Hampton, Va) In National Symposium on Helicopter Aerodynamic Efficiency, Hartford, Conn, March 6, 7, 1975, Proceedings New York, American Helicopter Society, Inc , 1975, p 9 1 9 10 20 refs The influence of the more independent airfoil parameters such as thickness, thickness distribution, leading-edge radius, camber, and camber distribution on lift Mach number characteristics is investi- gated at lift coefficients up to near maximum lift The analysis is based on the drag divergence Mach number (Md) prediction techniques, where Md is the free stream Mach number at which the rate of increase of drag coefficient with Mach number equals 0 1 The analytical results obtained indicate the compromises in Md which result from changes in thickness ratio, location of maximum thickness, leading edge radius, camber addition, and location of maximum camber for four and five digit airfoils and some six senes airfoils of potential interest for helicopters An example of airfoil sections which combines several of the favorable geometric changes is evaluated analytically and experimentally A comparison of results shows that the relative effect of the geometric changes on the lift coefficient Md relation is realistic, and that the methods of analysis employed can be effectively used during preliminary vehicle design and airfoil selection S D A75-38350 ;7 A tunnel spanning airfoil testing technique D R Chaddock (US Naval Material Command, Ship Research and Development Center, Bethesda, Md ) In National Symposium on Helicopter Aerodynamic Efficiency, Hartford, Conn , March 6, 7, 1975, Proceedings New York, American Helicopter Society, Inc, 1975, p 12 1-12 12 6 refs Several helicopter airfoil blade sections are tested in a transonic wind tunnel in order to obtain transonic two-dimensional data The airfoil models are described along with the transonic wind tunnel of rectangular cross-section Center span pressures are integrated to calculate lift, pitching moment, and drag A wake rake is used to measure wake total and static pressures which are integrated to calculate drag All data are measured simultaneously by using scam-valves under identical conditions for a constant angle of attack, and balance data are averaged for each data point Comparisons 399 A75-38351 between integrated surface pressure data, balance data, and wake rake transverse show that the integrated pressure data give displaced curves, reduced pitching moments, and are consistent with the balance drag data Wake rake data indicate a lower level and different gradient for the drag rise as a function of angle of attack than either the pressure or the balance data Means of reducing discrepancies between the measuring techniques are discussed S D A75-38351 A simplified approach to generalized heli- copter configuration modeling and the prediction of fuselage surface pressures T W Sheeny (United Aircraft Corp , Sikorsky Aircraft Div, Stratford, Conn ) In National Symposium on Helicopter Aerodynamic Efficiency, Hartford, Conn, March 6, 7, 1975, Proceedings New York, American Helicopter Society, Inc , 1975, p 1 5 1 1 5 8 An analytical method using well tried potential flow techniques has been developed to analyze the aerodynamic flow field on and about aircraft configurations To simplify the use of the techniques, a computer aided method to generate analytical models of aircraft configurations has been developed The method has demonstrated good correlation with experimental data and its potential for being a beneficial design tool In addition, the computer modeling technique developed reduces user responsibility while accurately modeling the configuration analyzed (Author) A75-38352 ff Wasted fuel - Another reason for drag reduction J P Rabbott, Jr and R H Stroub (U S Army, Air Mobility Research and Development Laboratory Moffett Field, Calif ) In National Symposium on Helicopter Aerodynamic Efficiency, Hartford, Conn , March 6, 7, 1975, Proceedings New York, American Helicopter Society, Inc, 1975, p 1 7 1 1 7 6 14refs The effects of changes in helicopter parasite drag on fuel costs in the period 1970-1990 are reviewed for both the civil and military fleet Factors considered include the fleet mix of light, medium and heavy helicopters and the gradual phasing out of in-service heli- copters and introduction of more modern designs This leads to a composite fleet cruise speed and equivalent flat plate parasite drag area An equivalent speed for fuel utilization is defined and yearly parasite drag fuel costs computed based on current parasite drag design practices Three improved levels of drag technology are postulated and associated potential savings in fuel costs presented It is concluded that the potential savings in fuel costs are measured in tens of millions of dollars per year (Author) A75-38353 # Effects of parasite drag on rotor performance and dynamic response A F Smith (Kaman Aerospace Corp, Blumfield, Conn ) In National Symposium on Helicopter Aero- dynamic Efficiency, Hartford Conn , March 6, 7, 1975, Proceedings New York, American Helicopter Society, Inc, 1975, p 18 1-186 A coupled aeroelastic analysis including two elastic modes and three rigid body response modes is used to compute the rotor response of a typical helicopter with the aid of FORTRAN IV language The effect of drag on rotor dynamic loadings, bending moment distributions, blade section angle of attack, rotor power, and hub shears is evaluated over a range of forward flight speeds and typical rotor loading conditions It is shown that (1) increasing helicopter flat plate area increases rotor power, tip angle of attack, blade flapping, resultant hub shears, and higher harmonic flatwise bending moments, but reduces first harmonic flatwise bending moments, and (2) every additional square foot of drag reduces rotor maximum forward speed by 2 5 knots S D A75-38354 ff Effect of helicopter drag reduction on rotor dynamic loads and blade life A W Kerr (Lockheed-California Co , Burbank, Calif) In National Symposium on Helicopter Aero- dynamic Efficiency, Hartford, Conn , March 6, 7, 1975, Proceedings New York, American Helicopter Society Inc 1975, p 19 1 197 ' Helicopter drag as reflected in rotor propulsive force require- ments has a significant effect on dynamic blade loads which can affect blade life These loads also generate excitation for airframe vibrations A detailed analysis has been made to assess the impact of helicopter drag on blade and rotor hub loads Predicted dynamic loads are presented for a 16,000 pound helicopter with a four-bladed stiff-mplane hingeless rotor flying at 150 knots with airframe (including hub and pylon) parasite drag levels between 0 and 30 square feet of equivalent flat-plate drag area The analysis used is described briefly and correlation with flight data shown The significance of dynamic loads on blade life and airframe vibration are discussed Reduction of airframe drag level decreases vibration excitation and blade loads significantly, which can result in opportunity for weight reduction and a secondary impact on extension of blade life (Author) A75-38355 II Cost benefit evaluation of helicopter parasite drag reductions J M Duhon (Bell Helicopter Co , Fort Worth, Tex ) In National Symposium on Helicopter Aerodynamic Efficiency, Hartford, Conn , March 6, 7, 1975, Proceedings New York, American Helicopter Society, Inc , 1975, p 161 163 The paper discusses means of evaluating the effect of drag reduction on empty weight, cost to manufacture, and cost to operate Drag reduction in the design phase is shown to be much more effective than such reduction attempted in the development or product improvement phase The paper proposes guidelines for determining how much weight and how many dollars can be expended beneficially on drag reduction A numerical example shows cost and weight evaluation for a simple commercial application (Author) A75-38356 * " A comprehensive plan for helicopter drag reduction R M Williams and P S Montana (US Naval National Command, Ship Research and Development Center, Bethesda, Md ) In National Symposium on Helicopter Aerodynamic Efficiency, Hartford, Conn , March 6, 7, 1975, Proceedings New York, American Helicopter Society, Inc, 1975, p 13 1-1326 31 refs Navy NASA-Army supported research Current helicopters have parasite drag levels 6 to 10 times as great as fixed wing aircraft The commensurate poor cruise efficiency results in a substantial degradation of potential mission capability The paper traces the origins of helicopter drag and shows that the problem (primarily due to bluff body flow separation) can be solved by the adoption of a comprehensive research and development plan This plan, known as the Fuselage Design Methodology, comprises both nonaerodynamic and aerodynamic aspects The aerodynamics are discussed in detail and experimental and analytical programs are described which will lead to a solution of the bluff body problem Some recent results of work conducted at the Naval Ship Research and Development Center (NSRDC) are presented to illustrate these programs It is concluded that a 75 per cent reduction of helicopter drag is possible by the full implementation of the Fuselage Design Methodology (Author) A75-38357 # A study of the potential benefits of advanced airfoils for helicopter applications V M Paghno and D R Clark (United Aircraft Corp , Sikorsky Aircraft Div , Stratford, Conn ) In National Symposium on Helicopter Aerodynamic Efficiency, Hartford, Conn , March 6, 7, 1975, Proceedings New York, American Helicopter Society, Inc , 1975, p 11 1 11 15 6 refs Contract No N00019-73-G 0225 An analytical study is made of the potential benefits of advanced airfoils for helicopter applications Representative missions are defined and partial derivatives are developed which relate specific airfoil characteristics to rotor aerodynamic efficiency and to heli- copter design gross weight Selected airfoils are incorporated in design applications so that computed aerodynamic benefits are interfaced with rotor dynamic limitations, structural weight require- ments, and cost elements It is demonstrated that airfoil im- provements may contribute to reduction in power required, increases 400 A75-38576 in load carrying capacity for a given blade area, or increased load factor capability during maneuvers This study addresses the reduced power or performance benefits only (Author) A75-38358 A review of design objectives for advanced helicopter rotor airfoils L U Dadone and T Fukushima (Boeing Vertol Co , Philadelphia, Pa ) In National Symposium on Helicopter Aerodynamic Efficiency, Hartford, Conn, March 6, 7, 1975, Proceedings New York, American Helicopter Society, Inc , 1975, p 10 1-10 18 19 refs The mam features of several recent advanced airfoils are reviewed in order to define the degree of commonality present in the guidelines under which they were developed and, when possible, to explain the differences in design objectives The advanced airfoils are discussed under three categories modifications of the NACA 0012 airfoil, modified versions of high speed cambered airfoils, and transonic airfoils designed for helicopter rotors based on methodolo- gy for high-speed fixed wing applications The flow environment of a helicopter rotor and the key sectional characteristics for hover and forward flight are examined The sectional characteristics necessary to improve Vertol rotors are determined through several airfoil design, airfoil test and rotor test iterations It is shown that while the design guidelines under which all advanced helicopter airfoils are developed recognize the importance of high lift, low pitching moments, and good high Mach number performance, only the Vertol guidelines actually specify a lower limit for the maximum lift coefficient and prescribe nose-up pitching moments S D A75-38370 Looping in a hydrogen cooling system I N Moisheev {Teplofizika Vysokikh Temperatur, vol 12, Nov -Dec 1974, p 1257-1266 ) High Temperature, vol 12, no 6. July 1975, p 1103-1110 Translation The present paper considers the problem of circuit design for a forced hydrogen cooling system for aircraft subjected to high heat loads The hydrogen in such systems is used both as a fuel and as a coolant Two methods of using the hydrogen are compared a single-circuit method and a double circuit method In the single- circuit system, the hydrogen flows directly in a cooling jacket, where it is heated In the double-circuit system, the aerodynamically generated heat is accumulated by a high-temperature heat-transfer agent which circulates in a closed circuit, then the heat is transferred to the hydrogen coolant in a high-temperature heat exchanger A liquid-metal heat-transfer agent is used in the present case It is shown that the double-circuit system can offer considerable advantages over a single circuit system, especially for high heat loads A T S A75-38375 Reflection of a shock wave from a wedge G A Makarevich, O A Predvoditeleva, and G S Lisenkova (Teplo- fizika Vysokikh Temperatur, vol 12, Nov-Dec 1974, p 13181321) High Temperature, vol 12, no 6, July 1975, p 1172-1175 12 refs Translation Experimental studies were made of the reflection of shock waves of various intensities in the region of intermediate angles between regular and irregular reflections A wedge-shaped model was used in an electric-discharge shock tube 80 mm in diameter During the experiments, the Mach number was 1 85, 6, or 10, and the initial pressure in the tube was varied from 4 to 30 torr High-speed motion pictures were made at rates from 125,000 to 187,000 frames/sec A T S A75-38406 H Hypersonic flow past V-shaped conical wings (Giperzvukovoe obtekanie konicheskikh kryl'ev V-obraznoi formy) A L Conor and N A Ostapenko Moskovskn Gosudarstvennyi Universitet. Institut Mekhamki, Otchet no 1164, 1971 24 p 23 refs In Russian An analytical method is proposed for calculating a hypersonic flow past a conical wing Assuming that the flow patterns are curvilinear Mach shock waves and that the region of turbulent flow is a strongly compressed layer, a closed solution is constructed which allows regions bounded by a contact discontinuity as well as bow and internal shock waves to be joined smoothly It is shown that the problem reduces mathematically to the solution of two integro- differential equations On the basis of an approximate solution, the characteristics of the flow field are determined, and the maximum L/D ratio is established with a wing conic angle of less than 180 deg F G M A75-38407 # Integral method for calculating a detached stream behind a body in a supersonic flow (Integral'nyi metod rase he t a otryvnogo techenna za telom v sverkhzvukovom potoke) L V Gogish and G lu Stepanov Moskovskn Gosudarstvennyi Universitet, Institut Mekhamki, Otchet no 1188, 1971 36 p 25 refs In Russian A stream behind a body in a supersonic flow is examined taking into account the basic characteristics of the flow about its leading edge the presence of shock waves and entropic layers, the nature of the boundary layer, and its interaction with an mviscid stream Characteristic subregions of the stream in the wake are delimited, and stream conditions in these subregions are formulated for viscous and mviscid flow layers with allowance for their interaction Integral relations are obtained in a general form for two-dimensional viscous and mviscid gas flows in jets, layers, and wakes, and a simple method for calculating detached streams is constructed on the basis of these relations together with assumptions about velocity profiles, boundary layers, and closure relationships Simple approximations are described for calculating a turbulent boundary layer and the wake in a gas with arbitrary pressure and heat exchange gradients FG M A75-38550 # LTA aerodynamic data revisited H C Curtiss, Jr, D C Hazen, and W F Putman (Princeton University, Princeton, N J ) American Institute of Aeronautics and Astronautics, Lighter Than Air Technology Conference, Snowmass, Colo, July 1517, 1975, Paper 75-951 17 p 38 refs Sources of aerodynamic data for lighter than-air vehicles are surveyed, and their probable accuracy is critically evaluated It is noted that most of the cited literature was published prior to 1930 Attention is restricted to essentially fully buoyant craft employing conventional airship-shaped hulls of more or less circular cross section and fineness ratios ranging from 3 to 10 Major topics discussed include drag, lift, and sideforce aerododynamics, equilib num flight, dynamic stability, and controllability It is shown that modern analytical methods based on boundary layer and flow theory should be utilized to obtain more reliable data on drag effects as well as hull forces and moments Previously published papers on estimation of stability derivatives, response rates, coupling effects, and controllability are found to be less than satisfactory due to the inadequate testing method of the time It is suggested that analytical predictive techniques be employed in these areas without experi- mental verification F G M A75-38576 •;' New structural form of sandwich core K Miura (Tokyo, University, Tokyo, Japan) Journal of Aircraft, vol 12, May 1975, p 437-441 The purpose of this study is to present a new structural form of sandwich core The observation, that the characteristics of honey- comb core is distinctly attributable to its stabilized perpendicular wall elements, leads to the possibility of a hypothetical core concept characterized by stabilized oblique wall elements To embody the hypothetical concept, the core form constituted by superposing two mutually orthogonal corrugations is proposed The resultant core can be manufactured from a single sheet by some press forming technique The theoretical and experimental analyses of the core reveal that the shear modulus and strength are comparable with those of honeycomb core, and the elastic properties can be designed to be either isotropic or orthotropic Other features of the core such as the simplicity of form, the applicability to both flat and curved sandwiches, and the possibility of circulating fluid between facings, may excite new applications of sandwich construction in aircraft structures (Author) 401 A75-38579 A75-38579 # Static stability and aperiodic divergence G Sachs (Darmstadt, Techmsche Hochschule, Darmstadt, West Germany) Journal of Aircraft, vol 12, May 1975, p 497500 6 refs The present work shows conditions under which static stability cannot prevent aperiodic divergence and indicates cases where static stability is and is not sufficient for dynamic stability Root locus analyses and stability boundary graphs are given for various aerodynamic quantities involved In the cases considered, stability is found to be sufficient for dynamic stability and sufficient to prevent aperiodic divergence S J M A75-38601 The acoustic response of a nozzle flow to an externally applied low frequency pressure field J R Jacques (Cambridge University, Cambridge, England) Journal of Sound and Vibration, vol 41, July 8, 1975, p 1332 17 refs A theoretical discussion is presented of the noise generated when a |et exhausts from a constant pressure plenum chamber into an unsteady atmosphere That unsteadiness provokes fluctuations at the nozzle exit and these are evaluated by taking into account a model of the axisymmetnc jet instability modes It is found that the radiated noise is virtually omnidirectional and that it depends strongly on both the jet Mach number and nozzle contraction ratio This sound mechanism vanishes completely when the |et becomes sonic Then, despite the unsteady external field, the nozzle flow is unperturbed The sound power radiated scales on the sixth power of jet speed so that it is likely to dominate over the jet mixing noise at low Mach number The mechanism can be driven by any aero- dynamic perturbation around the nozzle, but it is found that if the perturbation is acoustic, the scattered energy is an altogether negligible fraction of that incident on the nozzle area (Author) A75-38603 A social survey to examine the variance of aircraft noise annoyance R M Edwards (Loughborough University of Technology, Loughborough, Leics, England) Journal of Sound and Vibration, vol 41, July 8, 1975, p 41-51 10 refs Research supported by the Civil Aviation Authority The large variability in the measurement of human response to aircraft noise is described, and the philosophy behind a social survey designed to eliminate some causes of this variability, by considering a small geographical area over which the noise from one aircraft flyover is nearly constant, is outlined Results from this survey show that it is not noise measurements and noise indices that need improvement, but measures of human response Until we have a better measure of response than McKennell's Guttman Annoyance Scale efforts to improve noise indices are wasted The variability in annoyance score of the residents of the area studied is just as high as that in previous surveys in which NNI has been used as an Index to group areas of equal noise exposure Some objections to the operation of this particular Guttman scale are raised Analysis of the Coefficients of Reproducibility of the scale as used in various surveys shows that the scale has behaved differently in different surveys (Author) A75-38618 ff Turbulent near wake of a flat plate II - Effects of boundary layer profile and compressibility K Toyoda (Hokkaido Institute of Technology, Sapporo, Japan) and N Hirayama (Tokyo Metropolitan University, Tokyo, Japan) JSME, Bulletin, vol 18, June 1975, p 605611 12 refs In the previous report, we proposed a method to calculate the development of the incompressible turbulent wake close to a flat plate The calculated results were compared with experimental data in which the wake started from the turbulent boundary layers on both sides of a thin flat plate The agreement between the calculated and the experimental results was very good, and we can conclude that the diffusion phenomenon of the turbulent near wake has been made clear both qualitatively and quantitatively In that case the shape parameters of the boundary layers at the trailing edge of the plate were all equal to 1 45 Here in this report, we extend the previous method so that we can study the effect of the boundary layer profile and that of compressibility upon the development of the turbulent wake close to a flat plate The calculated results show that the wake profile is dependent on the boundary layer profile and compressibility The agreement between the calculated and the experimental results is excellent (Author) A75-38629 Possibilities concerning a use of borescope inspection methods in nondestructive material testing and the significance of these methods (Moglichkeiten der Borescope- Untersuchungsmethoden in der zerstorungsfreien Werkstoffprufung und deren Aussagekraft) H -G Straatmann (Lufttransport Unternehmen GmbH, Dusseldorf, West Germany) (Deutsche Gesellschaft fur Zerstorungsfreie Prufverfahren, Vonragstagung uber Zerstorungsfreie Matenalpnifung, Berlin, West Germany, May 5-7, 1975) Matenalpnifung, vol 17, July 1975, p 220,221 In German Industrial glass fiber borescopes are used for the examination of cavities in the case of accessibility difficulties The employment of the borescope technique in the case of an inspection involving an aircraft engine is discussed The engine consists of five different modules Openings for borescope inspection are provided in each module G R A75-38668 UTTAS Air International, vol 9, Aug 1975, p 67-74 Two competing designs for the Utility Tactical Transport Aircraft System (UTTAS) are outlined The UTTAS will be a utility transport helicopter powered by twin turboshaft engines Although only slightly advanced over the UH-1, which it is to replace, in terms of troop capacity, the UTTAS will have greater payload capacity in high-temperature and high-altitude operations, superior performance, and improved reliability and availability Cutaway drawings of the two designs are provided P T H A75-38726 # Spike, relays and aircraft electric systems 0 Markowitz (U S Navy, Aviation Supply Office, Philadelphia, Pa ) In Annual National Relay Conference, 23rd, Oklahoma State University, Stillwater, Okla, April 29, 30, 1975, Proceedings Conference sponsored by the Oklahoma State University and National Association of Relay Manufacturers Scottsdale, Ariz, National Association of Relay Manufacturers, 1975, p 12-1 to 12-14 8 refs A spike is produced by the interruption of current flow or a sudden change in current level that releases stored magnetic energy Spike generators are considered to be aircraft relays, solenoids, magnetic clutches, actuators, pulsing switches, motors, transformers, and the like The specific characteristics of a spike are translated into generic characteristics which are used for defining the spike A review of the existing approaches to spike suppression in a relay suggests that a directed total approach is required by the relay industry to provide the optimal system approach to relay suppression A basic spike generator circuit is presented along with an aircraft electric system design S D 402 N75-25871 STAR ENTRIES N76-25863 Georgia Inst of Tech . Atlanta DYNAMIC STALL CHARACTERISTICS OF AN OSCILLATING AIRFOIL IN A HARMONICALLY VARYING FREESTREAM VELOCITY Ph D. Thesis John Bruce Malone 1974 184 p Avail Univ Microfilms Order No 75-13001 The unsteady freestream environment of a helicopter rotor blade in forward flight was simulated using a gust generator mechanism installed in a low-turbulence wind tunnel A model is used for this investigation An operational analog computer is used to obtain both the aerodynamic moment acting on the model, and the work done by the moment during pitching oscillations of the airfoil The experimental tests indicate that the unsteady freestream can produce large changes in the shape of the aerodynamic moment versus angle of attack hysteresis loops The test results also show that the stability of the system can be adversely affected by the unsteady freestream under certain parametric conditions Dissert Abstr N75-25865 Virginia Polytechnic Inst and State Univ Blacksburg INVESTIGATION OF THE TURBULENT PROPERTIES OF THE WAKE BEHIND SELF PROPELLED. AXISYMMETRIC BODIES Ph D Thesis Chmg-Chang Chieng 1974 125 p Avail Univ Microfilms Order No 75-11930 The turbulent wakes behind a streamlined drag body a jet-propelled body and a propeller-driven body are studied experimentally in stability wind tunnel at a nominal free stream velocity of 206 ft/sec The turbulence properties investigated are axial, radial, and tangential turbulence intensities and radial and tangential shear stresses Data was taken at five axial stations downstream of the tail of the body X/D = 2. 5, 10, 20 and 40 It is found that the propeller-driven body produces the largest wake throughout the axial distance covered by these tests The jet-propelled body produces the middle sized wake compared to the other two models up to the station X/D = 20 beyond this station this wake becomes the smallest Dissert Abstr N75-25866 Virginia Polytechnic Inst and State Univ Blacksburg TURBULENT WAKE BEHIND SLENDER BODIES. INCLUD- ING SELF-PROPELLED CONFIGURATIONS PhD Thesis Roy Charles Swanson Jr 1975 115 p Avail Univ Microfilms Order No 75-11950 The turbulent wakes behind a streamlined drag body a jet-propelled body and a propeller-driven body are studied experimentally in a subsonic wind tunnel at a principal nominal freestream velocity of 206 ft/sec The wakes produced by the latter two bodies are momentumless Mean flow data taken at five axial stations (X/D =2 5 10, 20 and 40) downstream of the sterns of these bodies include velocity and static pressure distributions The streamwise variation of the maximum values of axial turbulence intensity and radial shear stress are also presented The mean flow data for the wake behind the drag body compare favorably with previous experiments and establish a rigid reference for the wakes behind slender self-propelled configurations Dissert Abstr N75-25867 Stanford Univ Calif POTENTIAL FLOW ABOUT THREE-DIMENSIONAL STREAMLINED LIFTING CONFIGURATIONS. WITH APPLICATION TO WINGS AND ROTORS Ph D Thesis James Michael Summa 1975 158 p Avail Univ Microfilms Order No 75-13606 A numerical method is developed and successfully applied for converging to the exact calculation of three-dimensional lifting potential flows including cases of unsteady motion The exact body surface boundary conditions are enforced, and all wake surfaces are unconstrained The assumptions made in the theoretical model are that the fluid is ideal and that no separation may take place The basic solution consists of the Green's function approach, where the velocity potential at any point in the fluid is represented by continuous distribution of doublets of unknown strength on each of the bounding surfaces Application of the surface tangency condition yields a set of coupled, singular Fredholm integral equations of the first kind relating the velocity potential doublet distributions to the normal velocity on the body surfaces and subject to the Kutta-Joukowski condition at trailing edges and the dynamic and geometric surface conditions on all wakes Dissert Abstr N76-26868# National Aviation Facilities Experimental Center Atlantic City. NJ THE MEASUREMENT OF THE BOEING 707 TRAILING VORTEX SYSTEM USING THE TOWER FLY-BY TECHNIQUE Final Report, Oct. • Nov 1972 Leo Garodz, David Lawrence, and Nelson Miller Mar 1975 124 p refs (AD-A008384. FAA-NA-74-37. FAA-RD-75-15) Avail NTIS HCS525 CSCL01/1 The results are presented for a series of low-altitude flight tests in which the trailing vortices of the Boeing 707 airplane were investigated using a 140-foot tower instrumented with airspeed, velocity, direction temperature, and humidity sensors Flow visualization was employed and motion picture records made The data presented consists of plots of vortex tangential velocity distribution, peak tangential velocity as a function of time, airplane configuration, windspeed, and airplane altitude in proximity to the tower, vortex descent rates, lateral transport velocities, and specimen time histories of the velocities measured by individual sensors Author N75-25870*# National Aeronautics and Space Administration Langley Research Center Langley Station. Va COMPARISON OF MEASURED AND CALCULATED AIRCRAFT LIFT GENERATED PRESSURES Donald S Fmdley Jun 1975 17 p refs (NASA-TM-X-72707) Avail NTIS HC $3 25 CSCL01A Lift generated pressures produced by large heavy aircraft at low altitudes were investigated due to concern over their possible effects on ground objects Aircraft lift generated pressures were calculated using elementary airfoil theory, and these values were compared with ground level measurements made during an overflight program The predicted and the measured values were in relatively good agreement Due to lack of experimental investigations of this phenomenon opportunity was taken during an overflight program to use a specially instrumented test range to measure the ground pressures produced for a range of aircraft weights and distances Author N76-25871 *# Boston Univ , Mass Coll of Engineering STEADY AND OSCILLATORY. SUBSONIC AND SUPER- SONIC. AERODYNAMIC PRESSURE AND GENERALIZED FORCES FOR COMPLEX AIRCRAFT CONFIGURATIONS AND APPLICATIONS TO FLUTTER M S Thesis Lee-Tzong Chen 1975 201 p refs (Grant NGR-22-004-030) (NASA-CR-142983) Avail NTIS HC $7 25 CSCL 01A A general method for analyzing aerodynamic flows around complex configurations is presented By applying the Green function method, a linear integral equation relating the unknown small perturbation potential on the surface of the body, to the known downwash is obtained The surfaces of the aircraft wake and diaphragm (if necessary) are divided into small quadrilateral elements which are approximated with hyperboloidal surfaces The potential and its normal derivative are assumed to be constant within each element This yields a set of linear algebraic equations and the coefficients are evaluated analytically By using Gaussian elimination method equations are solved for the potentials at the centroids of elements The pressure coefficient is evaluated by the finite different method, the lift and moment coefficients are evaluated by numerical integration Numerical results are presented, and applications to flutter are also included Author 403 N75-25874 N75-25874*# Mississippi State Univ. Mississippi State Aerophysics and Aerospace Engineering NUMERICAL SOLUTION OF THE NAVIER-STOKES EQUA- TIONS FOR ARBITRARY TWO-DIMENSIONAL MULTI- ELEMENT AIRFOILS Semiannual Status Report, 1 Jan. - 30 Jun 1975 Joe F Thompson 1 Jul 1975 8 p (Grant NGR-25-001-055) (NASA-CR-143038) Avail NTIS HC $3 25 CSCL 01A Abstracts are presented on a method of numerical solution of the Navier-Stokes equation for the flow about arbitrary airfoils, using a numerically generated curvilinear coordinate system having a coordinate line coincident with the body contour Results of continuing research are reported and include application of the Navier-Stokes solution in the vorticity-stream function formulation to a number of single airfoils at Reynolds numbers up to 2000, programming of the Navier-Stokes solution for multiple airfoils in the primitive variable formulation testing of the potential flow solution of multiple bodies and development of a generalized coordinate system program L B N75-26876# Technion - Israel Inst of Tech Haifa Oept of Aeronautical Engineering AERODYNAMIC EFFECTS OF VORTEX SUPPRESSORS H Portnoy Jul 1974 20 p refs (Grant AF-AFOSR-2145-71, AF Proj 6813, AF Proj 9781) (AO-A003750 TAE-221, AFOSR-75-0013TR, SR-4) Avail NTIS CSCL 01/1 The effectiveness of various devices in accelarating the dissi- pation of wing-tip vortices has received consideraole attention re- cently These devices include |ets blown into or near the vortex core, both in the upstream and downstream direction, small cruci- form wings, both fixed and rotating mounted close behind the wing near tip and angled fences or vortex generators mounted on the wing upper and lower surfaces so as to produce swirl opposite to that of the tip vortex In this report are proposed mathemati- cal models for representing some of these devices in order to calculate their effects on the wing aerodynamic properties These models are incorporated into a lifting-line theory and examples are calculated for high-aspect-ratio, unswept untwisted wings of the elliptic planform In order to obtain results of a more useful kind, it is suggested that these models be used with a lifting-surface theory of the vortex-lattice type GRA N76-26877# Flow Research, Inc , Kent Wash BOUNDARY LAYER TRANSITION ON BLUNT BODIES Scientific Report, 15 Jan - 14 Jul 1974 Denny R S Ko Charles L Merkle and Toshi Kubota Oct 1974 8 p refs (Contract F44620-74-C-0049, AF Proj 4730A) (AD-A004826, AFOSR-75-0191TR) Avail NTIS CSCL 16/2 The results of linear stability theory have been used to predict the location of boundary-layer transition with emphasis on including the effects of surface roughness and axisymmetric geometry Both of these parameters are important in determin- ing transition on re-entry vehicles The effects of surface roughness were included by means of a turbulent sublayer model which attributes the effects of roughness to an alteration in the mean velocity profile Axisymmetric effects were included by a proper consideration of the growth rate of the boundary-layer thick- ness GRA N75-25878# Army Aviation Engineering Flight Activity Edwards AFB Calif ARTIFICIAL ICING TESTS CH-47C HELICOPTER Final Report. 8 Apr - 2 May 1974 Carl F Mittag James C OConnor, and Louis Kronenberger, Jr Aug 1974 71 p (AD-A004008. USAAEFA-73-04-1) Avail NTIS CSCL 01/3 The United States Army Aviation Engineering Flight Activity conducted a limited evaluation of the CH-47C helicopter in artificial icing conditions from 8 April 1974 through 2 May 1974 These tests were conducted at Moses Lake, Washington and consisted of 2 9 hours in an artificial icing environment Artificial icing tests were conducted to evaluate the capability of the CH-47C helicopter to safely operate in an icing environment and to verify the icing limitations presented in the operator's manual Addition- ally, the capabilities of the standard anti-ice systems and installed special equipment were evaluated GRA N75-26879# Naval Postgraduate School Monterey Calif AERODYNAMIC CHARACTERISTICS OF AN AXISYM- METRIC BODY UNDERGOING A UNIFORM PITCHING MOTION PhD Thesis Lloyd Henry Smith Dec 1974 99 p refs (AD-A003859) Avail NTIS CSCL 16/2 An experimental investigation was conducted to determine the effect of a uniform pitching motion on a slender axisymmetric body while undergoing large excursions in angle of attack Force and moment measurements were obtained for a slender tangent-ogive/cylmdrical body over a range of Reynolds numbers from 50,000 to 140,000 while varying the angle of attack from zero to 90 degrees and the pitch rate between zero and 281 degrees per second Smoke flow visualization studies were used as an aid in assessing wake vortex transitions GRA N75-25881# Naval Air Development Center. Warmmster. Pa Air Vehicle Technology Dept AERODYNAMIC ANALYSIS OF A GENERAL PURPOSE TOW TARGET J B Smith 3 Dec 1974 21 p refs (AD-A003497, NADC-74132-30) Avail NTIS CSCL 01/3 This report presents the aerodynamic characteristics of a proposed aerial tow target configured to meet the general purpose tow target requirements of the Navy Standard Tow Target System The General Purpose Tow Target will serve as a target for missile and gunnery weapon firing exercises and will be capable of air launch and recovery GRA N75-25882# Marquardt Corp. Van Nuys, Calif A/A 47U-3 TOW TARGET REELING MACHINE LAUNCHER SYSTEM Dec 1974 16 p Revised (AD-A004622) Avail NTIS CSCL 01/3 The A/A 47 U-3 target launcher designed to provide target towing capability for subsonic and supersonic military aircraft is described Performance, design features, operation installation, and ground support equipment are included J M S N75-25883# Lockheed-Georgia Co Marietta A METHOD FOR PREDICTING ACOUSTICALLY INDUCED VIBRATION IN TRANSPORT AIRCRAFT. APPENDIX Final Report Harold W Bartel and Cecil W Schneider Sep 1974 54 p refs (Contract F33615-73-C-3638 AF Proj 1370) (AD-A004215. LG74ER01 2 1-App-1 AFFDL-TR-74-App-1) Avail NTIS CSCL 01/3 A method is set forth for predicting the acoustically induced structural vibration in transport category aircraft Charts are presented which correlate third-octave random noise and vibration levels at various confidence levels for the frequency range of 50 to 2500 Hertz The prediction charts are based on measured data from modern transport aircraft and are presented for the normal direction, ground operation, and a reference structural mass and rigidity Shell-type structure (fuselage, pods, fairings) and box-type structure (wing horizontal/vertical stabilizer) are treated separately Means are provided for predicting lateral and tangential vibration vibration in pressurized cruise flight, and for correcting for changes in structural mass and rigidity Application of the method to a hypothetical airplane design case is illustrated in an example GRA N75-25884/JI Lockheed-Georgia Co. Marietta REYNOLDS NUMBER EFFECTS ON THE BOATTAIL CHARACTERISTICS OF A SIMULATED NACELLE AT A MACH NUMBER OF 0 8 Final Report, 1 Dec 1973 - 8 Aug 1974 Ted Dansby Oct 1974 78 p refs (Contract F33615-74-C-4021 AF Proj 7064) (AD-A004803 LG74ER0078 ARL-74-0120) Avail NTIS CSCL 01/3 404 N75-25903 The effect of Reynolds number on the boattail drag of three simulated afterbody configurations is presented for zero angle of attack for a Mach number of 0 8 The boattail pressure drag for one of the configurations is shown to first decrease then significantly increase as the Reynolds number increases The behavior is explained by the regular variation of pressures in regions of the boattail The mechanism governing this behavior is discussed and is partially predicted from state-of-the-art theoretical techniques The influence of model installations and test techniques is shown to have a marked effect on the level of the drag GRA N75-25885# Advanced Technology Center, Inc Dallas Tex EXPERIMENTAL MATING OP TRAPPED VORTEX DIF- FUSERS WITH LARGE AREA RATIO THRUST AUG- MENTORS Final Report, Jun 1973 - Jan 1974 Charles H Haight and Robert M ODonnell Sep 1974 52 p refs (Contract F33615-73-C-4151 AF Proj 7116) (AD-A004802 B-94300/4CR-8 ARL-74-0115) Avail NTIS CSCL 01/3 The performance of a straight wall diffuser and various trapped vortex diffusers was measured with a basic ARL ejector as a test bed The straight wall diffuser. termed Configuration F by Aerospace Research Laboratories (ARU yielded thrust augmen- tation ratios in near agreement with those previously obtained by ARL Also, as noted by ARL the thrust augmentation of Configuration F was insensitive to changes in the primary injector pressure The trapped vortex diffusers investigated were of varying lengths GRA A six-degree-of-freedom simulation study was conducted to predict air launch separation characteristics of the MQM-74C aerial target drone from a DC-130A The effects of various launch aircraft flight conditions, flow field effects autopilot control system malfunction and loss of engine power on target separation characteristics were analyzed GRA N76-25894# Texas A&M Umv College Station Flight Mechanics Lab AERODYNAMIC SPOILER FOR PREVENTING AIRPLANE STALL/SPIN TYPE ACCIDENTS Final Report H I Chevalier Dec 1974 77 p refs (Contract DOT-FA73WA-3192) (AD-A006995 FAA-RD-75-21) Avail NTIS H C S 4 7 5 CSCL 01/3 A flight test investigation was conducted to evaluate the feasibility of an aerodynamic spoiler system installed on a Piper PA-30 airplane for deterring stall, and to determine its effective- ness as a stall deterrent for other light twin-engine general aviation airplanes Flight tests were conducted for the airplane without the spoiler installed, with the spoiler operated manually and with the spoiler operated automatically Test results were obtained for different c g locations, flap positions, and engine thrust Flight test maneuvers included approaches to stall from straight level flight, climbs, descents, turns slips and skids with both engines operating and with simulated single engine operation Tests also included takeoffs and landings Test results show that the spoiler concept is feasible for an airplane with a horizontal tail where the complete surface is moveable Author N75-25887# Air Force Systems Command Wright-Patterson AFB Ohio Foreign Technology Div A STUDY OF THE FLOW AROUND PLANE AND AXIALLY SYMMETRICAL BODIES WITH A SEPARATED SHOCK WAVE BY A FLOW AT LOW SUPERSONIC SPEED S M Gilmskn and M G Lebedev 6 Dec 1974 20 p refs Transl into ENGLISH from Akad Nauk SSSR Izv Mekhan (USSR) no 1 Jan - Feb 1965 p 17-23 (AD-A004442. FTD-MT-24-2287-74) Avail NTIS CSCL 20/4 This work is a continuation of the study of the flow around bodies of various forms by a supersonic flow of an ideal gas G F Telenin's method for the integration of equations of gas dynamics is used in the calculation of the flow around plane and axially symmetrical bodies by a flow at low supersonic speed Basically the range of Mach numbers M -2 is examined A comparison is carried out with experimental data and the results of calculations with the use of other numerical methods GRA N75-25891# Texas A&M Umv, College Station THEORETICAL PREDICTION OF AIRLOADS ON THIN DELTA WINGS IN INCOMPRESSIBLE FLOW B M Rao and W P Jones Jan 1975 46 p refs (Contract N00014-68-A-0308-0007) (AD-A004654. TEES-3029-75-01) Avail NTIS CSCL 01/1 Two methods are developed for the prediction of aerodynamic loads on sharp-edged delta wings in incompressible flow The first method is based on the application of the Polhamus suction analogy to the potential flow solution which is obtained in this paper by a unique numerical lifting surface method developed at Texas A and M University The second method is a direct extension of potential flow theory The mathematical model is modified by introducing a vortex system to represent the leading edge separation The strength of the separated vortices are adjusted by an empirical factor whose value is chosen in such a way that the total system gives the required lift GRA N75-25896$ Aeronautical Systems Div , Wright-Patterson AFB Ohio WET RUNWAY AIRCRAFT CONTROL PROJECT F 4 RAIN TIRE PROJECT Final Report. Mar 1971 - Oct 1974 William V Tracy Jr Oct 1974 383 p refs (AF Proj 5549) (AD-A004768 ASD-TR-74-37) Avail NTIS CSCL 01/3 This report presents the results of all efforts to study the prob- lem of wet runway control of the F-4 fighter aircraft The hardware tested is as follows Hytrol Mark II Brake Control System Hytrol Mark III Brake Control System, Standard Main Tire, Dunlop Mam Tire Sommer Mam Tire, BFG Mam Tire USAF Mam Tire. Dual Mode Hydro-Electrical Control Steering System, Standard Nose Tire, Dunlop Nose Tire BFG Nose Tire, and USAF Nose Tire In addition to this testing was also completed to determine the variation in mam tire spinup time with touchdown sink rate and the effect resulting from 50% worn main tires GRA N7B-26901*# Massachusetts Inst of Tech Cambridge Dept of Aeronautics and Astronautics FLIGHT TEST AND EVALUATION OF OMEGA NAVIGATION FOR GENERAL AVIATION Peter V Hwoschmsky Jun 1975 266 p refs (Grant NGL-22-009-640) (NASA-CR-132677) Avail NTIS HC $8 50 CSCL 17G A seventy hour flight test program was performed to determine the suitability and accuracy of a low cost Omega navigation receiver in a general aviation aircraft An analysis was made of signal availability in two widely separated geographic areas Comparison is made of the results of these flights with other navigation systems Conclusions drawn from the test experience indicate that developmental system improvement is necessary before a competent fail safe or fail soft area navigation system is offered to general aviation Author N75-25892# Naval Air Development Center Warmmster. Pa Dept of Air Vehicle Technology AIR LAUNCH CHARACTERISTICS OF THE MQM-74C TARGET DRONE FROM DC-130A AIRPLANE Mark Lempert 9 Jan 1975 125 p refs (AD-A004190. NADC-74079-30) Avail NTIS CSCL 01/3 N75-25903# Naval Postgraduate School, Monterey. Calif IMPROVEMENT OF AN/TPQ-27 FILTER AND CONTROL TECHNIQUES M S Thesis Robert Eugene Lentz Dec 1974 201 p refs (AD-A003878) Avail NTIS CSCL 17/7 405 N75-25905 A modified linear Kalman filter with deterministic forcing is used to improve the tracking capabilities of the Marine Corps AN/TPQ-27 remote tactical aircraft guidance system Both sixth and ninth order filters are developed and used with the Precision and Coarse Guidance simulation programs A technique for overcoming the effects of autopilot bias is presented and tested through simulation Precision Guidance control is modified to utilize angle error and angle error rate to generate corrective commands Significant improvement in aircraft state estimation, bombing accuracy, and overall system response is shown The Coarse guidance algorithms and simulation program perform aircraft guidance to the bombing run with more than adequate precision under simulated conditions GRA N75-26906# Aeronautical Systems Div Wright-Patterson AFB. Ohio A UNIVERSAL FLIGHT DIRECTOR COMPUTER Final Report Gerald W Francis Aug 1974 59 p (AD-A003634. ASD-TR-74-20) Avail NTIS CSCL 17/7 A technique is proposed which will make the flight director computer performance independent of aircraft dynamics, wind or aircraft position relative to the navigation beam The control law proposed will compensate for all such variables with an error correcting mechanism This technique results in a computer that is universal in its application GRA N76-26914* National Aeronautics and Space Administration Langley Research Center, Langley Station. Va HIGH LIFT AIRCRAFT Patent Willard S Blanchard, Jr and Joseph L Johnson, Jr, inventors (to NASA) Issued 20 May 1975 6 p Filed 5 Jun 1973 Supersedes N73-26007 (11-17. p 1980) (NASA-Case-LAR-11252-1. US-Patent-3 884.432. US-Patent-Appl-SN-367268. US-Patent-Class-244-15. US-Patent-Class-D12-76 US-Patent-Class-244-13, US-Patent-Class-244-42DA. US-Patent-Class-244-55) Avail US Patent Office CSCL 01C An aerodynamically balanced high-lift aircraft is proposed in which the problems of large nose-down pitching moments generated by the flap high-lift forces, the loss of trim lift during high-lift flight and the yawing moments caused by the loss of an engine are solved without the use of large horizontal and vertical tails A wing is carried by and bounced on the tips by spaced-parallel fuselages, horizontal tails are mounted only onto the outboard surfaces of the wing-tip fuselages the centroid-of-lift of the high-lift flaps is 'ocated substantially at the center of gravity of the aircraft and the exhausts of the engines are emitted in the vertical plane of symmetry of the aircraft Yawing moments ockurnng during flight with an engine inoperative are reduced, the horizontal tails carry an upload and contribute positive trim lift, large nose-down pitching moments generated by the high-lift flaps are minimized and noise levels are reduced Official Gazette of the U S Patent Office N76-26916* National Aeronautics and Space Administration Ames Research Center, Moffett Field, Calif SHOULDER HARNESS AND LAP BELT RESTRAINT SYSTEM Patent Albert P Garavaglia and Dennis S Matsuhiro, inventors (to NASA) Issued 3 Jun 1975 4 p Filed 19 Mar 1974 Supersedes N74-18805 (12 - 10, p 1137) (NASA-Case-ARC-10519-2 US-Patent-3,887,233, US-Patent-Appl-SN-452767. US-Patent-Class-297-389 US-Petent-Class-280-150SB US-Patem-Class-297-385, U S-Petent-Class-297-388) Avail US Patent Office CSCL 06Q A shoulder harness and lap belt restraint system are provided where the lap belt is combined with the shoulder harness so that a single fastening secures both the shoulder strap and the lap belt Official Gazette of the U S Patent Office N76-26916*# Douglas Aircraft Co, Inc. Long Beach. Calif ENGJNE/AIRFRAME COMPATIBILITY STUDIES FOR SUPERSONIC CRUISE AIRCRAFT May 1975 59 p (Contract NAS1-13229) (NASA-CR-132610-1 MDC-J4505-Suppl) Avail NTIS HC $425 CSCL 01C Engme/air f rame compatibilities are studied utilizing the advanced supersonic transport point design as the baseline for comparison Detailed studies of four engines are given The technical analysis, configuration descriptions, and study results are presented for each of the four specific engines studied M CF N76-26917*# National Aeronautics and Space Administration Ames Research Center, Moffett Field Calif A STOL AIRWORTHINESS INVESTIGATION USING A SIMULATION OF AN AUGMENTOR WING TRANSPORT VOLUME 2 SIMULATION DATA AND ANALYSIS Final Report Robert K Heffley. Robert L Stapleford, Robert C Rumold, John M Lehman, Barry C Scott, and Charles S Hynes Oct 1974 222 p refs Prepared in cooperation with Systems Technology. Inc, Mountain View, Calif and FAA, Moffett Field, Calif (Contract NAS2-7926) (NASA-TM-X-62396, AD-A006602, FAA-RD-74-179-Vol-2, A-5798) Avail NTIS CSCL 01/3 A simulator study of STOL airworthiness was conducted using a model of an augmentor wing transport The approach, flare and landing, go-around, and takeoff phases of flight were investigated The simulation and the data obtained are described These data include performance measures, pilot commentary, and pilot ratings A pilot/vehicle analysis of glide slope tracking and of the flare maneuver is included Author N76-26918*# Scientific Translation Service, Santa Barbara, Calif DESIGN OF AIRCRAFT WHEELS AND BRAKE SYSTEMS I I Zverev and S S Kokonm Washington NASA Jun 1975 260 p refs Transl into ENGLISH of the book "Proyektirovamye Aviatsionnykh Koles i Tormoznykh Sistem" Moscow. Mashmo- stroyeniye Press, 1973 224 p (Contract NASw-2483) (NASA-TT-F-15764) Avail NTIS HCS850 CSCL 01C The experience in the design and analysis of aircraft wheels and brakes, brake systems, brake control systems, and antiskid systems is summarized The static and fatigue strength of aircraft wheels, calculation of brake service life, brake dynamics, techniques for increasing brake energy absorption capacity, and design of the basic antiskid system elements are examined Author N75-26919# Fairchild Republic Div , Farmmgdale. NY PRELIMINARY DESIGN OF WINGS VOLUME 4 MINIMUM WEIGHT DESIGN OF COMPOSITE STRUCTURE Final Technical Report, Feb 1971 - Oct. 1972 Harold Switzky Mar 1974 56 p refs (Contract F33615-71-C-1241, AF Pro) 1368) (AD-A003667. AFFDL-TR-74-20-Vol-4) Avail NTIS CSCL 01/3 Minimum weight design procedures are developed for composite structure fabricated with plies oriented 0, plus or minus 45. and 90 degrees to the longitudinal axis and subjected to an arbitrary biaxial loading The design technique for stable structure is based upon a generalized ellipsoidal failure model which includes as special cases the classical models for orthotropic and isotropic structural behavior The strength and interaction parameters are established by a statistical fit of the available experimental data GRA N76-25921# Princeton U'niv, NJ Dept of Aerospace and Mechanical Sciences AN EXPERIMENTAL INVESTIGATION OF THE EFFECT OF A FUSELAGE ON WING CHARACTERISTICS Final Report, 1 Apr 1964 - 31 Mar. 1968 Fumio Yoshmo Oct 1975 215 p refs (Contract Nonr-1858(46). NR Proj 212-155) (AD-A003955, AMS-TB-1151) Avail NTIS CSCL 01/1 406 N75-25930 A series of experimental investigations utilizing flow visualiza- tion, force measurement and pressure distribution techniques to investigate the effect on wing lift of fuselage placement and cross-sectional shape are reported Emphasis is placed on conditions involving large circulation including the use Of circulation control GRA N76-26922# Naval Postgraduate School. Monterey, Calif AIRCRAFT FUEL TANK VULNERABILITY TO HYDRAULIC RAM: MODIFICATION OF THE NORTHROP FINITE ELEMENT COMPUTER CODE BR-1 TO INCLUDE FLUID- STRUCTURE INTERACTION THEORY AND USERS MANUAL FOR BR-1 HR Final Report. 1 Jul 1973 - 30 Jun. 1974 R E Ball Jul 1974 35 p refs (AD-A003471, NPS-57BP74071) Avail NTIS CSCL01/3 The finite element digital computer code BR-1, developed by the Northrop Corporation, for predicting the effects of internal air blast on combat aircraft structures is modified to include the effects of compressible fluid-structure interaction The true interaction phenomenon is approximated by the piston theory The modification enables the code to be used to predict the structural response of aircraft fuel tanks subjected to penetrating bullets end fragments GRA N76-26923# Army Aviation Engineering Flight Activity. Edwards AFB, Calif GUARDRAIL IIA RU-21H EVALUATION Final Report George M Yamakawa. Tom P Benson, and Larry K Brewer Jul 1974 34 p refs (AD-A004009, USAAEFA-74-35) Avail NTIS CSCL01/3 The United States Army Aviation Engineering Flight Activity conducted a flying qualities evaluation of the GUARDRAIL IIA RU-21H aircraft, manufactured by Beach Aircraft Corporation The RU-21H aircraft was tested at the Beech facility in Wichita, Kansas, on 11 and 12 May 1974 During the test program, 4 0 productive hours were flown The program included a stability and control evaluation and miscellaneous engineering tests necessary to provide substantiating data to aid the GUARDRAIL IIA airworthiness determination Within the scope of this test, the flying qualities of the GUARDRAIL IIA RU-21H aircraft are satisfactory GRA N75-26925# General Dynamics Corp , San Diego, Calif Convair Aerospace Div APPLICATION OF HIGH TEMPERATURE COMPOSITES TO AN AIRCRAFT COMPONENT Final Report. Jun 1973 - Mar. 1974 W F Wennhld May 1974 124 p refs (Contract N62269-74-C-0757) (AD-A003546, CASD-NSC-74-001) Avail NTIS CSCL11/4 The initial phase covered by this report was to include the design and analysis of two canard structures, one constructed primarily of boron/aluminum, the other primarily of graphite/ polyimide Both designs were then to be compared for weight saving, cost, and technical risk A decision was then to be made to build two canard structures for structural testing Depending upon the outcome of the evaluation, one of each material or two of one material would be built and tested A NASTRAN model was prepared and used in the sizing of structural elements Up to eight iterations were required in order to achieve a design which met the requirements The Gr/PI canard design was not successfully completed Because of the results with the Gr/PI canard, the effort was diverted to the B/AI configuration Two subelement specimen tests were performed in order to evaluate the use of boron/aluminum crossphed material in a reversing stress fatigue spectrum The testing showed that microcrackmg can occur in the aluminum matrix material and that additional testing is necessary A manufacturing plan and a production cost estimate were made for a canard with boron/aluminum skins and titanium substructure GRA N76-26926# Trans-Somes, Inc. Burlington, Mass HELICOPTER LIFT MARGIN SYSTEM Final Report Bradford W Edgerton and Sidney B Williams Dec 1974 48 p refs (Contract N00014-72-C-0001. NR Proj 213-087) (AD-A003917, Rept-80003. JANAIR-731003) Avail NTIS CSCL01/3 Helicopter power requirements are generally maximum when hovering out of ground effect Thus, takeoff and landing maneuvers are the most critical, since the power requirements may not be clear to the pilot at the time he must make the corresponding decisions Power deficiencies at takeoff or landing are very hazardous To maximize safety of takeoff and landing operations, a system has been devised which presents to the pilot his lift margin, a figure which represents the excess weight which could be accommodated under locally-existing barometric pressure, outside-air-temperature conditions, and engine and rotor system conditions GRA N76-26927# Georgia Inst of Tech. Atlanta School of Engineering Science and Mechanics MINIMUM WEIGHT DESIGN OF FUSELAGE TYPE STIFF- ENED CIRCULAR CYLINDRICAL SHELLS SUBJECT TO UNIFORM AXIAL COMPRESSION George J Simitees and Variddhi Ungbhakorn Aug 1974 147 p refs (Grant AF-AFOSR-2655-74. AF Pro] 9782) (AD-A004412, AFOSR-75-0137TR) Avail NTIS CSCL01/3 This report contains a technical procedure by which one may design a fuselage-type stiffened thin circular cylindrical shell to carry safely a specified uniform axial compression with minimum weight GRA N7B-2B928# Air Force Inst of Tech, Wright-Patterson AFB, Ohio School of Engineering AN INVESTIGATION OF THE DEPARTURE MODES OF A F-4D AIRCRAFT FROM A STEADY SIDESLIP FLIGHT CONDITION M S. Thesis Max L Hawkins Dec 1974 138 p refs (AD-A004795. GAE/MC/74-6) Avail NTIS CSCL01/1 This study consisted of modeling the motion of an F-4D with both the linear and non-linear equations of motion The characteristic roots of the linear equations were first analyzed to predict the unstable flight conditions in the high angle of attack flight regime The linear equations were then integrated to obtain a time history, and more explicit picture, of motion predicted by the characteristic roots when the aircraft is perturbed from the unstable condition The validity of the linear equations is then checked and a more detailed picture of the nature of the motion obtained by numerically integrating the non-linear equations of motion at the same flight condition GRA N76-26929# Air Force Inst of Tech , Wright-Patterson AFB, Ohio School of Engineering SEQUENTIAL ATTACK IN AERIAL COMBAT M.S Thesis Robert D Powell Dec 1974 71 p refs (AD-A004796, GAE/MC/74-7) Avail NTIS CSCL01/3 The main features of a new system of aerial combat tactics, called sequential attack, are discussed One of the primary maneuvers of this system, the pitchback. is modeled as a minimum time turn optimal control problem Optimized trajectories are found by the ordinary gradient method using a realistic model of the F-4 aircraft A simple rule of thumb is found which produces maneuvers whose final times differ from the optimal by less than one second over the region of principal interest GRA N76-26930# Air Force Inst of Tech, Wright-Patterson AFB, Ohio School of Engineering THE EFFECT OF ROLL RATE ON AIR COMBAT M.S. Thesis James W Tilley, II Dec 1974 64 p refs (AD-A004794, GAE/MC/74-4) Avail NTIS CSCL 01/3 A study was made to determine the effects of roll rate on air combat The effects of increased roll rate responses were analyzed by comparing various performance parameters at specific times during three maneuvers the high speed yo-yo, the high speed barrel roll, and the low speed barrel roll The parameters compared were (1) the range between an attacking and defending aircraft, (2) the difference in specific energy between an attacking 407 N75-25931 and defending aircraft, and (3) the velocity difference between the attacker and defender GRA N76-26931# Air Force Inst of Tech, Wright-Patterson AFB, Ohio School of Engineering ANALYTICAL DETERMINATION OF AIRCRAFT SPIN MODES M.S. Thesis David L Westgate Dec 1974 77 p refs (AD-A004798, GAE/MC/74-11) Avail NTIS CSCL01/3 Six non-linear equations of motion for a rigid body are used to model the aircraft's motion while in a spin After applying the conditions for an equilibrium spin, the resulting six non-linear simultaneous equations are solved using a method that is accurate and well suited for use with a high-speed digital computer The solution yields the equilibrium spin conditions and these solutions were usually obtained with less than three seconds of computer time These results are compared with the results from previous prediction schemes The linear characteristics of the aircraft about the equilibrium points are also presented The model chosen for this study was a delta-wing fighter configuration GRA N7B-2B932| Air Force Inst. of Tech, Wright-Patterson AFB, Ohio School of Engineering DESIGN OF A DEPLOYABLE WING GLIDER M.S. Thesis Phillip L Abold Dec 1974 77 p refs (AD-A004800 GAE/MC/74D-1) Avail NTIS CSCL01/3 An unpowered, unguided vehicle to be deployed from a 4 75 inch flare tube was designed The design criteria were six cubic inch, two pound payload, minimum glide speed of 50 knots, and stable with particular emphasis on heading stability Two basic configurations were considered in the analysis the first was a tailless vehicle, and the second was a conventionally tailed vehicle It was found that the tailless vehicle could not meet the stability requirements and thus the tailed vehicle was chosen to meet the design criteria The analysis procedure consisted of a computer model to analyze vehicle stability, wind tunnel tests to calculate aerodynamic derivatives, and flight tests to demonstrate performance The finalized vehicle had a folding wing and flexible tail-boom to meet the packaging requirement The resulting vehicle had a glide ratio of 25 and was very stable in heading, while meeting all other design requirements GRA N75-25933# Naval Postgraduate School, Monterey, Calif INVESTIGATION OF THE A 7 HOOK POINT ATTACHMENT LOOSENING PROBLEM M S Thesis Allen William Roessig, Jr Dec 1974 76 p refs (AD-A004256) Avail NTIS CSCL01/3 Loosening of the hook point attachment bolt in the aircraft arresting hook assembly of the A-7 attack aircraft has caused a potentially dangerous situation and has demanded considerable maintenance effort This report reviews the history of the loosening problem and attempted solutions to it Research into a hitherto neglected possible causal mechanism, self loosening, is discussed Experiments designed to evaluate the contribution of this new factor to the problem are reported The conclusions drawn from these tests are that loosening occurs as a result of plastic strain of the bolt that the crushing of the washer also causes loss of torque, and that the existence or non-existence of a self loosening contribution could not be established GRA N75-25934# Bell Helicopter Co. Fort Worth. Tex APPLICATION OF ROTORCRAFT FLIGHT SIMULATION PROGRAM (C81) TO PREDICT ROTOR PERFORMANCE AND BENDING MOMENTS FOR A MODEL FOUR-BLADED ARTICULATED ROTOR SYSTEM Final Report. Jan 1973 - Jul 1974 F D Freeman and R L Bennett Nov 1974 268 p refs (Contract DAAJ02-72-C-0086, DA Proj 1F1-63204-D-157) (AD-A004015. BHC-299-099-691 USAAMRDL-TR-74-70) Avail NTIS CSCL01/3 Four sets of model H-34 helicopter rotor blades were built and tested by the Sikorsky Aircraft Corporation Rotorcraft Flight Simulation Program with Aeroelastic Rotor Representation Program C81, was used to predict rotor performance and blade bending moments for comparison with the test results Perform- ance predictions made using the steady-state two-dimensional airfoil data (GFE) supplied by the Army for the model airfoils showed stall characteristics at much lower rotor lift levels than recorded in the tunnel test Application of unsteady aerodynamic and yawed flow effects did not sufficiently improve the perform- ance correlation The lift and stall characteristics of the model rotor in the tunnel were found to be very similar to full-scale 0012 airfoil properties GRA N76-26936# Parsons of California. Stockton DESIGN CONCEPTS FOR HELICOPTER PALLETS AND GONDOLAS Final Report C Weber and R Young Nov 1974 179 p refs (Contract DAAJ02-73-C-0058, DA Pro] 1F1-62203-AA-33) (AD-A004013. USAAMRDL-TR-74-91) Avail NTIS CSCL 01/3 This report presents the results of the design concepts investigation and preliminary design of externally suspended cargo pallets and/or gondolas to be utilized with the CH-47, CH-54, and HLH helicopters Results of the investigation demonstrated that gondolas of two sizes could be coupled to develop full payload capacity of any of the three helicopters The basic gondola was right rectangular to accommodate vehicles and equipment or break-bulk cargo if required The investigation and supporting analyses eliminated pallets with lifting points at the base which make it both unstable and structurally inefficient Therefore pallets were not considered as a viable design concept The gondola provides compatibility with ANSI/ISO geometry and can be transported with slings or other load acquisition equipment GRA N75-25936# Mechanical Technology, Inc. Latham, NY APPLICATION OF HIGH FREQUENCY RESONANCE TECHNIQUES FOR BEARING DIAGNOSTICS IN HELICOP- TER GEARBOXES Final Technical Report Mark S Darlow. Robert H Badbley, and G W Hogg Oct 1974 177 p (Contract DAAJ02-73-C-0086, DA Proj 1F1-62205-A-119) (AD-A004014, MTI-74TR25, USAAMRDL-TR-74-77) Avail NTIS CSCL 01/3 The feasibility of the High-Frequency Resonance Technique (HFRT) for defect analysis of rolling-element bearings found in a UH-1 helicopter mam transmission was demonstrated A study was conducted to determine optimum conditions under which to test each bearing These included accelerometer location speed, load, housing design and detection frequency The results provided general testing criteria for each bearing An analytical and experimental bearing race resonance study was conducted on each bearing The bearings were then mounted in a test rig and run at various speeds, loads and housing designs Good bearings and bearings with artificially-induced discrete defects were run GRA N75-26942# Shock and Vibration Information Center (Defense) Washington, D C THE SHOCK AND VIBRATION DIGEST. VOLUME 6. NO 12 Dec 1974 168 p refs (AD-A003455) Avail NTIS CSCL 20A The various fan noise sources are discussed which are believed to be of significance in modern high bypass ratio engines Such fans operate at both subsonic and supersonic tip speeds and these two operating regimes are discussed separately The analytical techniques which have been evolved to calculate the noise are described Both the classical and the more recently developed methods are considered Author N76-25944*# National Aeronautics and Space Administration Lewis Research Center. Cleveland, Ohio TURBOFAN COMPRESSOR DYNAMICS DURING AFTER- BURNER TRANSIENTS Anatole P Kurkov 1975 17 p refs Presented at the Symp on Unsteady Phenomena in Turbomachmery. Monterey, Calif 408 N75-25961 22-26 Sep 1975, sponsored by A G A R D Propulsion and Energetics Panel (NASA-TM-X-71741 E-8375) Avail NTIS HC $3 25 CSCL 21E The effects of afterburner light-off and shut-down transients on compressor stability were investigated Experimental results are based on detailed high-response pressure and temperature measurements on the Tf30-p-3 turbofan engine The tests were performed in an altitude test chamber simulating high-altitude engine operation It is shown that during both types of transients flow breaks down in the forward part of the fan-bypass duct At a sufficiently low engine inlet pressure this resulted in a compressor stall Complete flow breakdown within the compressor was preceded by a rotating stall At some locations in the compressor, rotating stall cells initially extended only through part of the blade span For the shutdown transient, the time between first and last detected occurrence of rotating stall is related to the flow Reynolds number An attempt was made to deduce the number and speed of propagation of rotating stall cells Author N75-25946*# National Aeronautics and Space Administration Ames Research Center, Moffett Field, Calif WIND TUNNEL MEASUREMENTS OF FORWARD SPEED EFFECTS ON JET NOISE FROM SUPPRESSOR NOZZLES AND COMPARISON WITH FLIGHT TEST DATA Adolph Atencio Jr May 1975 10 p refs Presented at AIAA Sth Fluid and Plasma Dyn Conf Hartford 16-18 Jun 1975 Prepared in cooperation with Army Air Mobility R and D Lab. Moffett Field, Calif (NASA-TM-X-62449. A-6054) Avail NTIS HC S3 25 CSCL 20A The results of a test program conducted in the NASA Ames 40- by 80-Foot Wind Tunnel to determine the effect of forward speed on the noise levels emanating from a conical ejector nozzle, a 32-spoke suppressor nozzle, and a 104-elliptical- tube suppressor nozzle are reported It is shown that noise levels are reduced as forward speed is increased and that, for one suppressor configuration, forward speed enhances suppression Comparisons of noise measurements made m the wind tunnel with those obtained in flight tests show good agreement It is concluded that wind tunnels provide an effective means of measuring the effect of forward speed on aircraft noise Author N76-2B948*# National Aeronautics and Space Administration Lewis Research Center, Cleveland, Ohio INTERIM PREDICTION METHOD FOR FAN AND COMPRES- SOR SOURCE NOISE M F Heidmann Jun 1975 83 p refs (NASA-TM-X-71763, E-8398) Avail NTIS HCS475 CSCL 21E A method is presented for interim use in assessing the noise generated by fans and compressors in turbojet and turbofan engines One-third octave band sound pressure levels consisting of broadband, discrete tone, and combination-tone noise components are predicted Spectral distributions and directivity variations are specified The method is based on that developed by other investigators with modifications derived from an analysis of full-scale, single-stage fan data Comparisons of predicted and measured noise performance are presented, and requirements for improving the method are discussed Author N75-25949# Avco-Everett Research Lab , Everett Mass FIELD TESTS OF A LASER RAMAN MEASUREMENT SYSTEM FOR AIRCRAFT ENGINE EXHAUST EMISSIONS Final Technical Report Donald A Leonard Oct 1974 181 p refs (Contract F33615-71-C-1875, AF Pro) 3066) (AD-A003648. AFAPL-TR-74-100) Avail NTIS CSCL 07/4 Laser induced Raman and fluorescence measurements were made in the exhaust of a T53-L13A gas turbine engine with a new field portable instrument devised specifically for gas turbine exhaust emission measurements The gas turbine exhaust was analyzed by conventional instruments for CO. C02. NO. NOx, total hydrocarbons, smoke and temperature, and these data were used as a calibration standard for the evaluation of the laser Raman instrument The most severe problem area was laser induced hydrocarbon fluorescence when the exhaust contained large total hydrocarbon concentrations The overall conclusion was that the laser Raman method shows a good potential for aircraft gas turbine emission analysis GRA N75-26950# Pratt and Whitney Aircraft. West Palm Beach. Fla Research and Development Center MODIFIED CENTRIFUGAL COMPRESSOR Final Report. 23 Oct 1973 - 23 Jul 1974 Gary B Reeves and Jeffrey K Schweitzer Nov 1974 83 p (Contract DAAJ02-74-C-0003, DA Proj 1G2-62207-AH-89) (AD-A004002, PWA-FR-6583. USAAMRDL-TR-74-96) Avail NTIS CSCL 21/5 A single-stage centrifugal compressor designed to produce a 10 1 pressure ratio at a flow rate of 3 2 Ib/sec was tested An earlier version of this compressor was tested under US- AAMRDL Contract DAAJ02-70-C-0006 and was found to have excessive losses in the tandem mducer In addition, diffuser damage was incurred during that testing, which also prevented the achievement of the full design potential The objective of this follow-on program was therefore to demonstrate improved performance for the 10 1 pressure ratio single-stage centrifugal compressor with a modified inducer and a new (undamaged) diffuser Modifications to the design of the inducer were made to improve its high-speed (Mach number) performance and to decrease the required inlet prewhirl and a test program was conducted to obtain overall and inducer performance data GRA N76-26959 Stanford Univ Calif SELECTION OF SAMPLING RATE FOR DIGITAL CONTROL OF AIRCRAFTS Ph D Thesis Paul Katz 1975 242 p Avail Univ Microfilms Order No 75-13537 The considerations in selecting the sampling rate for a digital control of aircrafts are identified and evaluated Optimal discrete synthesis is the design method used Due to discretization of the continuous plant this method of design does not introduce an artificial limitation on the sampling rate The principal example used is the short period mode of a hypothetical high performance aircraft The assumed model includes a bending mode and wind gusts Major factors which influence the selection of the sampling rate are identified and investigated (1) the time response to control inputs. (2) the response to an external disturbance, (3) the sensitivity to variation of parameters, and (4) the roughness of the response to control inputs It was found that the limiting factors in the selection of the sampling rate for the example are the time response to a control input, and the response to an external disturbance Dissert Abstr N76-25961# Deutsche Forschungs- und Versuchsanstalt fuer Luft- und Raumfahrt, Bad Godesberg (West Germany) Abteilung Luftfahrtpsychologie COCKPIT-SYSTEM STUDY YAK 40 A PILOT OPINION SURVEY TO THE AIRCRAFT HANDLING AND SYSTEM QUALITIES Konrad Stetnmger and Guenter Neumann 2 Jan 1975 72 p In GERMAN, ENGLISH summary Sponsored by Bundesmin fuer Verkehr (DLR-FB-75-15) Avail NTIS HC $4 25 DFVLR. Porz, West Ger 24.90 DM A representative sample of pilots employed with an airline operating the Russian short haul jet transport aircraft YAK 40 assessed the acceptability of the cockpit layout and instrumenta- tion, the handling quality, and the feasibility of the systems with regard to the pilot's workload The assessment of the concerned qualities was quantitatively conducted by using a 7-scale rating of 82 items of a questionnaire, and qualitatively by tape-recorded descriptions of critical experiences with the aircraft The method of subjective assessment, rating, and description of a system was used to find the critical weakness and the favorable points of an aircraft-operation It is a heuristic 409 N75-25962 approach towards a direct recognition of the strain and attention needed to cope with the operation of the aircraft Author (ESRO) N76-26962# Lear Siegler, Inc . Oklahoma City, Okla Manage- ment Services Div FLIGHT CONTROL ACTUATOR SYSTEM DEVELOPMENT Final Report, 24 Nov 1972 - 18 Dec 1973 Dale G Bazill, Harry S Schreadley, and B H Earley Aug 1974 225 p (Contract F33615-73-C-3024, AF Pro) 8225) (AD-A004853. AFFDL-TR-74-82) Avail NTIS CSCL 01/3 This report describes the following research tasks The test and evaluation of a quadruplex redundant Pitch Axis Test Rig (PATR) to fully describe the hydraulic, mechanical and electronic technology contained therein, and the design of a Roll Axis Test Rig (RATR) to permit hardware simulation of quad redundant, force sharing, active standby, median select and split surface flight control system mechanizations that have high dynamic response GRA N76-26963# Air Force Inst of Tech, Wright-Patterson AFB, Ohio School of Engineering STABILITY ANALYSIS OF AN F-4C AIRCRAFT IN STEADY LEVEL TURNING FLIGHT M S Thesis Richard J Rudolph Dec 1974 74 p refs (AD-A004797, GAE/MC/74-9) Avail NTIS CSCL 01/3 A stability analysis of an F-4C aircraft (SAS off) in a coordinated, constant velocity, steady level turn is performed The linearized nondimensional equations of motion were used to solve for equilibrium positions about the steady turn and for the resulting aircraft motions Five flight regions were investi- gated to determine the effects of altitude and speed variations for load factors ranging from 1 0 to 3 0 in 0 5 increments Root locus plots and Argand diagrams are employed to isolate and identify three complex motions Results indicate adverse dutch rolling motion present at moderate load factors for several flight regions GRA N75-25967# Rome Air Development Center, Griffiss AFB, N Y FAA LIGHTNING PROTECTION STUDY LIGHTNING PROTECTION FOR STATUS AND CONTROL LINES OF AN/GRN-27IV) INSTRUMENT LANDING SYSTEM Final Report. 1 Jan 1974 - 1 Feb. 1975 Gene K Huddleston Feb 1975 26 p refs (Contract DOT-FA72WAI-356) (AD-A006997, FAA-RD-75-24) Avail NTIS HC S3 75 CSCL 01/5 Specific recommendations for the protection of the AN/GRN- 27 (5) instrument landing system from lightning-induced transients on the buried control cables comprising the status and control lines of the system are presented Avalanche diode transient voltage suppressors in leadless packages are the recommended protection devices Author N75-26137*# National Aeronautics and Space Administration Lewis Research Center Cleveland Ohio FRICTION AND WEAR OF CARBON-GRAPHITE MATERI- ALS FOR HIGH ENERGY BRAKES Robert C Bill Washington Jun 1975 28 p refs Prepared in cooperation with Army Air Mobility R and D Lab Cleveland (NASA-TN-D-8006 E-8259) Avail NTIS HC $375 CSCL 11G Cahper-type brakes simulation experiments were conducted on seven different carbon-graphite material formulations against a steel disk material and against a carbon-graphite disk material The effects of binder level, boron carbide (B4C) additions, graphite fiber additions and graphite cloth reinforcement on friction and wear behavior were investigated Reductions in binder level and additions of B4C each resulted in increased wear The wear rate was not-affected by the addition of graphite fibers Transition to severe wear and high friction was observed m the case of graphite-cloth-remforced carbon sliding against a disk of similar composition This transition was related to the disruption of a continuous graphite shear film that must form on the sliding surfaces if low wear is to occur The exposure of the fiber structure of the cloth constituent is believed to play a role in the shear film disruption Author N76-26149*# Kanner (Leo) Associates. Redwood City Calif FUEL FOR COMPRESSION MICROMOTORS A V Babichev Washington NASA Jul 1975 2 p Transl into ENGLISH from Russian Patent no 247713 (Appl no 1085220/23-4 23 Jun 1966) 1 p (Contract NASw-2481) (NASA-TT-F-16446) Avail NTIS HC $3 25 CSCL21D This fuel for a compression micromotor contains kerosene aviation oil, castor oil amyl nitrite, nitrobenzene and ethyl ether Calcium dioctylphenyldithiophosphate, a rugged, antiwear and antisconng substance is added to improve motor starting, to increase its service life by 45-50% and decrease scale formation AS-6 lubricating oil is added to decrease scale formation Cyclohexane is added to attain a 20-25% increase in fuel economy The proposed fuel is used in modeling aircraft, ships, motor vehicles and air-cushion craft Author N75-26152# Materials Research Labs Manbyrnong (Australia) THEORETICAL PREDICTIONS OF THERMAL EXPLOSIONS PART 1 A MATHEMATICAL MODEL OF A BOMB IN A FIRE D B Stroud Feb 1975 21 p refs (Rept-623-Pt-1) Avail NTIS HC $3 25 A mathematical model is proposed for describing the flow of heat into a bomb and the subsequent build-up to explosion when the bomb is placed in a large, aviation fuel fire The model has been used to predict the time to explosion for various bombs and good agreement is obtained with experimental values from the literature The time to explosion has also been calculated for a bare bomb and for one covered by a thermally protective coating under various fire conditions Several calcula- tions have been performed to determine the sensitivity of the time to explosion to changes in some of the input parameters Author N75-26273# Rockwell International Corp, Los Angeles Calif Aircraft Div INFLUENCE OF SOLID STATE ELECTRICAL DISTRIBUTION ON AIRCRAFT POWER GENERATION SOLID STATE POWER CONTROLLER COMPATIBILITY Final Report. Jan - Aug 1974 S Dawson. J E Phillips and R Urdanivia 27 Jul 1974 228 p (Contract F33615-72-C-1759 AF Proj 3145) (AD-A003834. AFAPL-TR-74-86) Avail NTIS CSCL 09/3 A compatibility study and engineering test evaluation on solid state power controllers (SSPC) was conducted to provide documentation and technical information to the Air Force of the factors needed for the technical decision of compatibility of SSPC on the B-1 air vehicle Part I of this report documents the Baseline Analysis Weight-Volume NA-72-229-1 The Supple- ment to the report contains a summary of a series of evaluation tests on Solid State Power Com,oilers The tests, were intended to verify operational characteristics of these devices in simulated B-1 environments and with simulated and actual B-1 loads GRA N75-26323# Pennsylvania State Univ University Park Applied Research Lab ON THE INVESTIGATION OF CASCADE AND TURBOMA- CHINERY ROTOR WAKE CHARACTERISTICS PhD Thesis Rishi Rai Nov 1974 206 p refs (Contract N00017-73-C-1418) (AD-A003580. TM-74-267) Avail NTIS CSCL 21/5 The objective of the investigation reported in this thesis is to study the mean and turbulence characteristics of a tur- bomachmery rotor wake, both analytically and experimentally The turbulence closure problem for the rotor wake in general- ized tensors and non-mertial frame of reference is developed 410 N75-26973 Simplified solutions are obtained for the prediction of mean properties of the cascade and the rotor wake respectively as a function of the downstream distance from the trailing edge, pressure gradient and other parameters of the cascade and rotor geometry GRA N75-26336*# Rockwell International Corp Anaheim. Calif Electronic Research Div INVESTIGATION OF SYSTEM INTEGRATION METHODS FOR BUBBLE DOMAIN FLIGHT RECORDERS Final Report, 7 Jun 1973 - 9 Dec 1974 T T Chen 0 D Bohmng et al May 1975 240 p refs (Contract NAS1-12435) (NASA-CR-132643 C74-1041 /501) Avail NTIS HC $7 50 CSCL 14B System integration methods for bubble domain flight records are investigated Bubble memory module packaging and assembly, the control electronics design and construction field coils, and permanent magnet bias structure design are studied A small 60-k bit engineering model was built and tested to demonstrate the feasibility of the bubble recorder Based on the various studies performed, a projection is made on a 50 000 000-bit prototype recorder It is estimated that the recorder will occupy 190 cubic in, weigh 12 Ib, and consume 12 w power when all of its four tracks are operated in parallel at 150 kHz data rate Author N75-26693*# National Aeronautics and Space Administration Langley Research Center, Langley Station, Va A COMPUTER PROGRAM FOR FITTING SMOOTH SUR- FACES TO AN AIRCRAFT CONFIGURATION AND OTHER THREE DIMENSIONAL GEOMETRIES CharlotteB Craidon Washington Jun 1975 112 p refs (NASA-TM-X-3206. L-9934) Avail NTIS HC $5 25 CSCL 09 B A computer program that uses a three-dimensional geome- tric technique for fitting a smooth surface to the component parts of an aircraft configuration is presented The resulting surface equations are useful in performing various kinds of calculations in which a three-dimensional mathematical description is necessary Programs options may be used to compute information for three-view and orthographic projections of the configuration as well as cross-section plots at any orientation through the configuration The aircraft geometry input section of the program may be easily replaced with a surface point description in a different form so that the program could be of use for any three-dimensional surface equations Author N75-26780 Marconi-Elliott Avionic Systems Ltd Rochester (England) THE APPLICATION OF DISPLAYS IN NAVIGATION/ ATTACK SYSTEMS J T Shepherd In AGARD Electro-Opt Systems May 1975 19 p The use of display systems during the navigation/attack phase of an aircraft mission is outlined The types of display used and their advantages and limitations are discussed Author N75-26787 British Aircraft Corp Warton (England) Military Aircraft Oiv AIRCRAFT DESIGN IMPLICATIONS OF OPTO-ELECTRONIC SYSTEMS W I McFarlane In AGARD Electro-Opt Systems May 1975 22 p The application of electro-optical systems to low level aircraft and helicopters is discussed with particular emphasis on the installational problems of weight drag the need for transparencies and power and cooling requirements In addition the need for integration and matching of these systems with other equipments weapons and each other is illustrated from the point of view of optimizing the overall weapon system Finally an objective is stated whereby these new developments can be integrated to maximize the usefulness of the crew by providing them with the right information from the right sensor on the right display at the right time for them to take executive action Author N75-26968*# National Aeronautics and Space Administration Lewis Research Center, Cleveland Ohio EFFECT OF INLET INGESTION OF A WING TIP VORTEX ON COMPRESSOR FACE FLOW AND TURBOJET STALL MARGIN Glenn A Mitchell Washington Jul 1975 78 p refs (NASA-TM-X-3246 E-8213) Avail NTIS HCS475 CSCL 01A A two-dimensional inlet was alternately mated to a coldpipe plug assembly and a J85-GE-13 turbojet engine and placed In a Mach 0 4 stream so as to ingest the tip vortex of a forward mounted wing Vortex properties were measured just forward of the inlet and at the compressor face Results show that tngestion of a wing tip vortex by a turbojet engine can cause a large reduction in engine stall margin The loss in stall compressor pressure ratio was primarily dependent on vortex location and rotational direction and not on total-pressure distortion Author N 75-26970*1 Wichita State Univ Kans EXPERIMENTAL STUDIES OF FLOW SEPARATION AND STALLING ON A TWO-DIMENSIONAL AIRFOIL AT LOW SPEEDS H C Seetharam and W H Wentz, Jr Washington NASA Jul 1975 64 p refs (Grant NCR-17-003-021) (NASA-CR-2560) Avail NTIS HCS425 CSCL 01A Detailed measurements of flow fields associated with low-speed turbulent boundary layers were made for the 17% thick GA(W)-1 airfoil section at nominal angles of attack of 10 deg 14 deg and 18 deg Reynolds number 22 x 10, and Mach number 0 13 The data include pressure and velocity surveys of the pre- and post-separated regions on the airfoil and the associated wake The boundary layer characteristics including regions of separation on the airfoil are also presented Author N75-26972*# Old Dominion Univ Norfolk Va School of Engineering THE FINITE ELEMENT METHOD IN LOW SPEED AERODY- NAMICS Final Technical Report A J Baker and P D Manhardt (Textron Bell Aerospace) May 1975 73 p refs (Grant NsG-1038) (NASA-CR-143190, TR-75-T5) Avail NTIS HCS425 CSCL 01A The finite element procedure is shown to be of significant impact in design of the computational wind tunnel for low speed aerodynamics The uniformity of the mathematical differential equation description for viscous and/or inviscid, multi-dimensional subsonic flows about practical aerodynamic system configurations is utilized to establish the general form of the finite element algorithm Numerical results for inviscid flow analysis as well as viscous boundary layer parabolic and full Navier Stokes flow descriptions verify the capabilities and overall versatility of the fundamental algorithm for aerodynamics The proven mathematical basis coupled with the distinct user-orientation features of the computer program embodiment indicate near-term evolution of a highly useful analytical design tool to support computational configuration studies in low speed aerodynamics Author N75-26973*# Bell Helicopter Co Fort Worth Tex DIGITAL COMPUTER PROGRAM DF1758 FULLY COUPLED N A T U R A L FREQUENCIES AND MODE SHAPES OF A HELICOPTER ROTOR BLADE R L Bennett 6 Mar 1975 120 p (Contract NAS1-13722) (NASA-CR-132662 Rept-299-099-724) Avail NTIS HC $525 CSCL 01 C The analytical techniques and computer program developed in the fully-coupled rotor vibration study are described The rotor 411 N75 26975 blade natural frequency and mode shape analysis was implemented in a digital computer program designated DF1758 The program computes collective, cyclic and scissor modes for a single blade within a specified range of frequency for specified values of rotor RPM and collective angle The analysis includes effects of blade twist eg offset from reference axis and shear center offset from reference axis Coupled inplane, out-of-plane and torsional vibrations are considered Normalized displacements, shear forces and moments may be printed out and Calcomp plots of natural frequencies as a function of rotor RPM may be produced Author N75-26975*# National Aeronautics and Space Administration Ames Research Center Moffett Field Calif DETAILED TRANSONIC FLOW FIELD MEASUREMENTS ABOUT A SUPERCRITICAL AIRFOIL SECTION Francis X Hurley Frank W Spaid Frederick W Roos Louis S Stivers Jr and Angelo Bandettmi Washington Jul 1975 64 p refs (NASA-TM-X-3244 A-5869) Avail NTIS HC $4 25 CSCL 01A The transonic flow field about a Whitcomb-type supercritical airfoil profile was measured in detail In addition to the usual surface pressure distributions and wake surveys schheren photographs were taken and velocity vector profiles were determined in the upper surface boundary layer and m the near wake Spanwise variations in the measured pressures were also determined The data are analyzed with the aid of an mviscid transonic finite-difference computer program as well as with boundary layer modeling and calculation schemes Author N75-26976*# Boeing Commercial Airplane Co Seattle Wash COMPARISON OF WIND TUNNEL TEST RESULTS AT FREE STREAM MACH 07 WITH RESULTS FROM THE BOEING TEA 230 SUBSONIC FLOW METHOD Final Report L W Mohn Washington NASA Jul 1975 91 p refs (Contract NAS1-12214) (NASA-CR-2554 06-41780) Avail NTIS HC $4 75 CSCL 01A The use of the Boeing TEA-230 Subsonic Flow Analysis method as a primary design tool in the development of cruise overwing nacelle configurations is presented Surface pressure characteristics at 0 7 Mach number were determined by the TEA-230 method for a selected overwing flow-through nacelle configuration Results of this analysis show excellent overall agreement with corresponding wind tunnel data Effects of the presence of the nacelle on the wing pressure field were predicted accurately by the theoretical method Evidence is provided that differences between theoretical and experimental pressure distributions in the present study would not result in significant discrepancies in the nacelle lines or nacelle drag estimates Author N75-26977*# National Aeronautics and Space Administration Langley Research Center Langley Station Va PROBLEMS OF FLIGHT IN TURBULENCE Gabriel Coupry Washington May 1975 35 p refs Transl into ENGLISH from Intern Council of the Aeron Sci Congr. 9th (Haifa Israel) 25-30 Aug 1974 15 p (NASA-TT-F-16401) Avail NTIS HC $3 75 CSCL 01A A description of mathematical models which can provide the aircraft designer with a practical representation of the flight environment encountered by an aircraft and classical models with new approaches both British and French, is presented It is shown by calculation of the response of a flexible aircraft to turbulence that as a rule the turbulence field should be considered as isotropic It is also shown how active control systems open the way to a next generation of aircraft that will be less sensitive to gusts Systems at present under test are described Author N75-26978# Nielsen Engineering and Research Inc Mountain View Calif SUPERSONIC LIFTING-SURFACE COMPUTER PROGRAM FOR CRUCIFORM WING-BODY COMBINATIONS Technical Report, 1 Oct 1973 - 30 Sep 1974 Marmx F E Dillenius and Jack N Nielsen Dec 1974 138 p refs (Contract N00014-74-C-0050 NR Pro) 215-226) (AD-A003925 NEAR-TR-74) Avail NTIS CSCL 16/2 A lifting-surface computer program has been written for supersonic cruciform wing-body combinations at combined pitch and yaw conditions The method involves supersonic line sources and doublets to model the body and uses Woodwards constant pressure panels to represent the wing Such panels are also placed on the body surface to account for wing-body inter- ference GRA N75-26979# Stanford Umv Calif Dept of Aeronautics and Astronautics POTENTIAL FLOW ABOUT THREE DIMENSIONAL STREAMLINED LIFTING CONFIGURATIONS. WITH APPLICATION TO WINGS AND ROTORS Interim Report J Michael Summa Sep 1974 160 p refs (Contract F44620-73-C-0036 AF Proj 9781 AF Pro) 6813) (AD-A003697 SU-DAAR-485 AFOSR-74-1914TR) Avail NTIS CSCL 01/1 A numerical method is developed and successfully applied which is believed capable of converging to the exact calculation of three-dimensional lifting potential flows including cases of unsteady motion The principal current limitation on its precision is restricted funds for computation The exact body surface boundary conditions are enforced, and all wake surfaces are unconstrained -- allowed to move with the local velocity field The assumptions made in the theoretical model are that the fluid is ideal (incompressible and mviscid) and that no sepa- ration may take place GRA N75-26980*# National Aeronautics and Space Administration Ames Research Center. Moffett Field Calif EXPLORATORY FLIGHT INVESTIGATION OF AIRCRAFT RESPONSE TO THE WING VORTEX WAKE GENERATED BY THE AUGMENTOR WING JET STOL RESEARCH AIRCRAFT Robert A Jacobsen and Fred J Drinkwater III May 1975 19 p refs (NASA-TM-X-62387 A-5753) Avail NTIS HC $3 25 CSCL 01C A brief exploratory flight program was conducted at Ames Research Center to investigate the vortex wake hazard of a powered-lift STOL aircraft The study was made by flying an instrumented Cessna 210 aircraft into the wake of the augmentator wing jet STOL research aircraft at separation distances from 1 to 4 n mi Characteristics of the wake were evaluated in terms of the magnitude of the upset of the probing aircraft Results indicated that within 1 n mi separation the wake could cause rolling moments in excess of roll control power and yawing moments equivalent to rudder control power of the probe aircraft Subjective evaluations by the pilots of the Cessna 210 aircraft supported by response measurements indicated that the upset caused by the wake of the STOL aircraft was comparable to that of a DC-9 in the landing configuration Author N75-26981# Naval Postgraduate School. Monterey. Calif A PROPOSAL TO IMPLEMENT STATISTICAL RELIABILITY ANALYSIS METHODOLOGY INTO THE NAVAL AVIATION MAINTENANCE PROGRAM M S Thesis Thomas Preston Driver and Herbert John Kressel Dec 1974 57 p refs (AD-A004264) Avail NTIS CSCL 15/5 The thesis investigates the decision logic utilized in the existing and planned aircraft maintenance programs of the United States Navy The authors' basic belief in the profit motive as an incentive for efficiency led to additional research into the decision logic employed by the commercial air carriers The conclusions reflect the contention that a statistical reliability based maintenance program would increase the efficiency of resource allocation and aircraft reliability Recommendations are proposed which would aid in the implementation of such a system GRA 412 N75-26989 N75-26982# National Transportation Safety Board Washington D C Bureau of Aviation Safety AIRCRAFT ACCIDENT REPORT AIR EAST, INC BEECH- CRAFT 99A. N125AE. JOHNSTOWN-CAMBRIA COUNTY AIRPORT. JOHNSTOWN. PENNSYLVANIA, 6 J A N U A R Y 1974 15 Jan 1975 32 p (PB-239891/5 NTSB-AAR-75-3) Avail NTIS HC S3 75 CSCL 01B Beechcraft 99A crashed while making an instrument approach to runway 33 at the Johnstown-Cambria County Airport Johnstown Pennsylvania Of the 15 passengers and 2 crewmem- bers aboard, 11 passengers and the captain were killed in the crash The four remaining passengers and the first officer were seriously injured The aircraft was destroyed While on an instrument landing system localizer approach the aircraft struck approach lights about 300 feet from the runway threshold and then crashed into an embankment about 200 feet from the threshold Shortly before and shortly after the accident the reported weather conditions at the Johnstown Airport consisted in part of variable 200- to 400-foot ceilings and a prevailing visibility of 2 miles in very light snow and fog The National Transportation Safety Board determines that the probable cause of this accident was a premature descent below a safe approach slope followed by a stall and loss of aircraft control GRA N75-26983# National Transportation Safety Board Washington D C Bureau of Aviation Safety AIRCRAFT ACCIDENT REPORT BRIEF FORMAT. U S CIVIL AVIATION ISSUE NUMBER 3 OF 1974 ACCIDENTS FILE NUMBERS 1-0002 THRU 1-0007. 1 0009 THRU 1-0019, 1-0021 THRU 1-0023. 1-0025 THRU 1-0028, 3-1034, 3-1444, 3-1801 THRU 3-2700 3 Jan 1975 547 p (PB-240364/0 NTSB-BA-74-7) Avail NTIS HC $12 50 CSCL 01B Selected aircraft accident reports are presented in brief format, occurring in U S Civil Aviation operations during calendar year t974 The brief format presents the facts conditions, circum- stances and probable cause(s) for each accident Additional statistical information is tabulated by type of accident, phase of operation kind of flying injury index, aircraft damage conditions of light pilot certificate injuries and casual factors GRA N75-26984# National Transportation Safety Board Washington D C Bureau of Aviation Safety A I R C R A F T ACCIDENT REPORT NEW JERSEY AIR NATIONAL GUARD F106. SERIAL NUMBER 59-0044. PIPER PA 24 250, N6876P, MIDAIR COLLISION NEAR SAXIS. VIRGINIA. 11 OCTOBER 1974 Aircraft Accident Report 29 Jan 1975 18 p (PB-240250/1 NTSB-AAR-75-6) Avail NTIS HCS325 CSCL 01B About 2023 eastern daylight time on October 11 1974. a New Jersey Air National Guard F106 and a Piper PA 24-250 N6876P collided in midair near Saxis. Virginia The National Transportation Safety Board determines that the probable cause of the accident was the failure of the interceptor pilot to see and avoid a civil aircraft during a high-speed low-altitude intercept training flight conducted in an area which included major north-south airways Also contributing to this accident was the system which permitted an incompatible mix of traffic in controlled airspace which resulted in the probability of an inadvertent radar lock-on to a civil aircraft GRA N75-26985# National Transportation Safety Board. Washington. D C Bureau of Aviation Safety AIRCRAFT ACCIDENT REPORT A I R C R A F T POOL LEASING CORPORATION. LOCKHEED SUPER CONSTELLA- TION. L-1049H. N6917C. MIAMI, FLORIDA. 15 DECEMBER 1973 11 Sep 1974 32 p (PB-240120/6. NTSB-AAR-74-11) Avail NTIS HC$3 75 CSCL 01B At 2353 est on December 15 1973 an Aircraft Pool Leasing Corporations Lockheed Super Constellation L-1049H which was operating as a cargo carrier crashed after takeoff from runway 9L of the Miami International Airport Miami Florida The probable cause of this accident was determined to be overrotation of the aircraft at lift-off resulting in flight m the aerodynamic region of reversed command near the stall regime and at too low an altitude to effect recovery The reason for the aircraft s entering this adverse flight condition could not be determined Factors which may have contributed to the accident include (a) improper cargo loading (b) a rearward movement of unsecured cargo resulting in a center of gravity shift aft of the allowable limit and (c) deficient crew coordination GRA N75-26986# National Transportation Safety Board Washington, D C Bureau of Aviation Safety AIRCRAFT ACCIDENT REPORT SATURN AIRWAYS INC . LOCKHEED L-382. N14ST. SPRINGFIELD. ILLINOIS, 23 MAY 1974 22 Jan 1975 37 p (PB-240119/8 NTSB-AAR-75-5) Avail NTIS HC $3 75 CSCL 01B About 1653 cdt May 23 1974 Saturn Airways Flight 14 crashed about 26 miles southeast of the Capital VOR near Springfield Illinois The outboard section of the left wing including the No 1 engine separated in flight from the remainder of the wing The National Transportation Safety Board determines that the probable cause of the accident was the undiscovered preexisting fatigue cracks which reduced the strength of the left wing to the degree that it failed as a result of positive aerodynamic loads created by moderate turbulence GRA N75-26987/J/ Texas Umv Austin Bureau of Business Research INVENTORY OF FREIGHT TRANSPORTATION IN THE SOUTHWEST PART 3 AIR FREIGHT SERVICE IN THE DALLAS-FORT WORTH AREA J Bryan Adair Jun 1974 83 p refs (Contract DOT-OS-30093) (PB-239820/4 DOT-TST-75/31 RR-6) Avail NTIS HC $475 CSCL 01 B An inventory is provided of existing air freight transportation facilities services and practices in the twenty-four Te.xas and two Oklahoma counties surrounding and including Dallas and Fort Worth Included in the inventory are details on air tonnages handled, volume trends an analysis of domestic and foreign air commerce ties information on airports, freight handling facilities, airlines, air freight forwarded and commmuter air carriers serving the area Products and commodities commmonly shipped to and from the Dallas-Fort Worth region by air are listed Actual and potential problem areas are considered for their possible influence on the air freight industry GRA N75-26988# National Transportation Safety Board Washington D C Bureau of Aviation Safety ANNUAL REVIEW OF AIRCRAFT ACCIDENT DATA. US GENERAL AVIATION. CALENDAR YEAR 1972 14 Nov 1974 207 p (PB-239608/3, NTSB-ARG-74-3) Avail NTIS HC$725 CSCL 018 The Annual Review of Aircraft Accident Data is a statistical compilation from reports of 4 256 general aviation accidents that occurred during calendar year 1972 Also included are 44 collisions between aircraft By coding each aircraft involved in the collisions an additional 44 records are produced, bringing total accidents records to 4300 GRA N75-26989# National Transportation Safety Board. Washington D C Bureau of Aviation Safety AIRCRAFT ACCIDENT REPORT NATIONAL AIRLINES. INCORPORATED. DC 10-10. N60NA. NEAR ALBUQUER- QUE. NEW MEXICO. 3 NOVEMBER 1973 15 Jan 1975 59 p (PB-239889/9. NTSB-AAR-75-2) Avail NTIS HCS425 CSCL 01B 413 N75-26990 On November 3 1973. at about 1640 MST, National Airlines. Inc Flight 27 was cruising at 39 000 feet, 65 nmi southwest of Albuquerque New Mexico, when the No 3 engine fan assembly disintegrated Fragments of the fan penetrated the fuselage the Nos 1 and 2 engine nacelles and the right wing As a result the cabin depressunzed and one cabin window which was struck by a fragment of the fan assembly separated from the fuselage A passenger who was sitting next to the window was forced through the opening and ejected from the aircraft The body of the passenger has not been recovered The aircraft was landed safely at Albuquerque International Airport The National Transportation Safety Board determines that the probable cause of this accident was the disintegration of the No 3 engine fan assembly as a result of an interaction between the fan blade tips and the fan case GRA N75-26990# National Transportation Safety Board Washington, D C Bureau of Aviation Safety AIRCRAFT ACCIDENT REPORT IBERIA LINEAS AEREAS DE ESPANA (IBERIAN AIRLINES) MCDONNELL DOUGLAS DC-10-30. EC CBN LOGAN INTERNATIONAL AIRPORT. BOSTON, MASSACHUSETTS, 17 DECEMBER 1973 „ 8 Nov 1974 33'p (PB-239890/7 NTSB-AAR-74-14) Avail NTIS HCS375 CSCL 01B About 1543 ESTon December 17 1973 Iberia Lmeas Aereas de Espana Flight 933 a DC-10-30 crashed while making an instrument landing system approach to runway 33 L at Logan International Airport Boston, Massachusetts Thirteen passengers were injured slightly two passengers and one flight attendant were injured seriously during evacuation The aircraft was substantially damaged The National Transportation Safety Board determines that the probable cause of this accident was that the captain did not recognize and may have been unable to recognize, an increased rate of descent in time to arrest it before the aircraft struck the approach light piers The captain s ability to detect and arrest the increased rate of descent was adversely affected by a lack of information as to the existence of the wind shear and the marginal visual cues available GRA N75-26991# Douglas Aircraft Co Inc Long Beach. Calif FEASIBILITY OF REAL TIME SIMULATION OF AIRPORT/ AIRSIDE OPERATIONS James B ONeill and R T White Mar 1975 42 p (Contract OOT-FA72WA-2897) (AD-A006996 FAA-RD-75-18) Avail NTIS HC $3 75 CSCL 17/7 All aspects of an airport airside are examined as are aspects of controller functions A possible real time simulator is defined for simulating the tower cab under conditions of zero visibility This system is composed of cathode ray tubes and driven by minicomputers to give a low cost portable system The number of displays required and the computer load for these systems are defined Application of the proposed system to several typical problems is discussed A detailed analysis of the engineering requirement and the human factors analysis of real time simulation are included Author N75-26994# Boeing Aerospace Co Seattle. Wash B-1 UNIQUE SIGNAL TRAIN GENERATION APPLICATION STUDY Final Report. 1 May - 30 Jun 1974 A R Mandell. E M Costello and D E Hightower Nov 1974 85 p -, (Contract F33657-72-C-0600 AF Pro) 2007) (AD-A003682 D229-1 0363-1. AFWL-TR-74-297) Avail NTIS CSfJL 01/3 The background requirement which underlies this study is consideration by the U S Atomic Energy Commission of the incorporation of a device in aircraft-delivered nuclear weapons which would be an additional series safety device in the weapon pre-arm circuits This device would be operated by a pulsating direct current signal whose format and implementation would be so unique that the possibility of its generation and application to the weapon by any means other than deliberate personnel action would be insignificantly small GRA N75-26995*# National Aeronautics and Space Administration Ames Research Center Moffett Field Calif COMPARISON OF TWO HEAD-UP DISPLAYS IN SIMULA- TED STANDARD AND NOISE ABATEMENT NIGHT VISUAL APPROACHES Fred Cronn (San Jose State Univ ) and Everett Palmer Washington Jul 1975 23 p refs (Grant NGL-05-046-002) (NASA-TM-X-3264 A-5993) Avail NTIS HC $3 25 CSCL 01D Situation and command head-up displays were evaluated for both standard and two segment noise abatement night visual approaches in a fixed base simulation of a DC-8 transport aircraft The situation display provided glide slope and pitch attitude information The command display provided glide slope information and flight path commands to capture a 3 deg glide slope Landing approaches were flown in both zero wind and wind shear conditions For both standard and noise abatement approaches the situation display provided greater glidepath accuracy in the initial phase of the landing approaches, whereas the command display was more effective in the final approach phase Glidepath accuracy was greater for the standard approaches than for the noise abatement approaches in all phases of the landing approach Most of the pilots preferred the command display and the standard approach Substantial agreement was found between each pilot s judgment of his performance and his actual performance Author N75-26996*# National Aeronautics and Space Administration Ames Research Center Moffett Field Calif THREE METHODS OF PRESENTING FLIGHT VECTOR INFORMATION IN A HEAD-UP DISPLAY DURING SIMU- LATED STOL APPROACHES James H Dwyer III and Everett A Palmer III Washington Jul 1975 16 p refs (NASA-TM-X-3273 A-5992) Avail NTIS HC $3 25 CSCL 01D A simulator study was conducted to determine the usefulness of adding flight path vector symbology to a head-up display designed to improve glide-slope tracking performance during steep 7 5 deg visual approaches in STOL aircraft All displays included a fixed attitude symbol a pitch- and roll-stabilized horizon bar, and a glide-slope reference bar parallel to and 7 5 deg below the horizon bar The displays differed with respect to the flight-path marker (FPM) symbol display 1 had no FPM symbol display 2 had an air-referenced FPM and display 3 had a ground-referenced FPM No differences between displays 1 and 2 were found on any of the performance measures Display 3 was found to decrease height error in the early part of the approach and to reduce descent rate variation over the entire approach Two measures of workload did not indicate any differences between the displays Author N75-26997*# McDonnell Aircraft Co St Louis Mo A FUSELAGE/TANK STRUCTURE STUDY FOR ACTIVELY COOLED HYPERSONIC CRUISE VEHICLES AIRCRAFT DESIGN EVALUATION T Nobe [1975] 116 p refs (Contract NAS1-12995) (NASA-CR-132668) Avail NTIS HC $5 25 CSCL01C The effects of fuselage cross sections and structural members on the performance of hypersonic cruise aircraft are evaluated Representative fuselage/tank area structure was analyzed for strength stability fatigue and fracture mechanics Various thermodynamic and structural tradeoffs were conducted to refine the conceptual designs with the primary objective of minimizing weight and maximizing aircraft range M C F N75-26998*# McDonnell Aircraft Co St Louis Mo A FUSELAGE/TANK STRUCTURE STUDY FOR ACTIVELY COOLED HYPERSONIC CRUISE VEHICLES ACTIVE 414 N75-27008 COOLING SYSTEM ANALYSIS James E Stone [1975] 104 p refs (Contract NAS1-12995) (NASA-CR-132669) Avail NTIS HCS525 CSCL01C The effects of fuselage cross section and structural arrange- ment on the performance of actively cooled hypersonic cruise vehicles are investigated An active cooling system which maintains the aircraft s entire surface area at temperatures below 394 K at Mach 6 is developed along with a hydrogen fuel tankage thermal protection system Thermodynamic characteristics of the actively cooled thermal protection systems established are summarized Design heat loads and coolant f lowrate requirements are defined for each major structural section and for the total system Cooling system weights are summarized at the major component level Conclusions and recommendations are included J M S N75-26999*# McDonnell Aircraft Co St Louis. Mo A FUSELAGE/TANK STRUCTURE STUDY FOR ACTIVELY COOLED HYPERSONIC CRUISE VEHICLES STRUCTURAL ANALYSIS Technical Report. 11 Mar 1974 - 30 Jun 1975 Allen H Baker [1975] 65 p refs (Contract NAS1-12995) (NASA-CR-132670) Avail NTIS HCS425 CSCL01C The effects of fuselage cross-section (circular and elliptical) and structural arrangement (integral and nonmtegral tanks) on the performance of actively cooled hypersonic cruise vehicles was evaluated It was found that integrally machined stiffening of the tank walls while providing the most weight-efficient use of materials results in higher production costs Fatigue and fracture mechanics appeared to have little effect on the weight of the three study aircraft The need for thermal strain relief through insulation is discussed Aircraft size and magnitude of the internal pressure are seen to be significant factors in tank design Author N75-27001*# Virginia Umv Charlottesville School of Engineering and Applied Science THE EFFECTS OF AIRCRAFT DESIGN ON STOL RIDE QUALITY Craig R Jones and Ira D Jacobson May 1975 103 p refs (Grant NGR-47-005-208) (NASA-CR-143113 ESS-4035-103-75) Avail NTIS HC $525 CSCL 01 C Effects of aircraft dynamic characteristics on passenger ride quality are investigated to determine ride-quality isocontours similar to aircraft handling-qualities contours Measurements are made on a moving-base simulator while varying the aircraft short-period and Dutch Roll frequencies and dampings Both pilot ratings and subjective ride-quality ratings are obtained during flight Ride and handling qualities were found to be complementary for the Dutch Roll mode, but not for the short-period mode Regions of optimal ride and handling qualities are defined for the short-period mode and the effects of turbulence levels studied Author N75-27002# Fairchild Republic Div Farmmgdale N Y PRELIMINARY DESIGN OF WINGS VOLUME 1 DESIGN PHILOSOPHY Final Technical Report, Feb 1971 - Oct 1972 Harold Switzky Mar 1974 39 p refs (Contract F33615-71-C-1241 AF Proj 1368) (AD-A003649 AFFDL-TR-74-20-Vol-1) Avail NTIS CSCL 01/3 A philosophy and methodology for performing preliminary designs of wings are presented The philosophy is to treat each segment of the problem with a different degree of completeness depending upon the present state of the art Each segment of the preliminary design is made as complete as possible within the constraints of obtaining a reliable and significant solution within a reasonable time In segments where an analytical philosophy exists assumptions are made to result in rapid and relatively accurate solutions In segments where it is not possible to establish analytical solutions semi-empirical statistical relationships are sought GRA N7'5-27003# Fairchild Republic Div , Farmmgdale N Y PRELIMINARY DESIGN OF WINGS VOLUME 2 PRE- LIMINARY FATIGUE DESIGN Final Technical Report. Feb 1971 - Oct 1972 Harold Switzky Mar 1974 37 p refs (Contract F33615-71-C-1241 AF Proj 1368) (AD-A003650 AFFDL-TR-74-20-Vol-2) Avail NTIS CSCL 01/3 This report describes an approach for obtaining ultimate tensile design allowables which should result in satisfactory fatigue performance Thus fatigue considerations can be included in the original design rather than being checked as an afterthought after the design has been set This can avoid costly redesigns to obtain structural integrity in fatigue GRA N75-27004# Fairchild Republic Div Farmmgdale NY PRELIMINARY DESIGN OF WINGS VOLUMES MINIMUM WEIGHT DESIGN OF STIFFENED PLATE Final Technical Report. Feb 1971 - Oct 1972 Harold Switzky Mar 1974 66 p refs (Contract F3361 5-71-C-1241 AF Pro) 1368) (AD-A003651 AFFDL-TR-74-20-Vol-3) Avail NTIS CSCL 01/3 A design philosophy based upon mathematical logic and structural behavior is developed to obtain the minimum weight design of determinate structures The philosophy is applied to stiffened skin constructions to obtain a nondimensional minimum weight design procedure and digital program which are readily applicable to any material temperature loading thickness stiffener spacing or height Techniques for improving the efficiency by choice of stiffener and material are also presented The assumptions utilized to analyze and design the structure are reviewed and their effect upon the weight and margin of safety of the design is assessed GRA N75-27005# Naval Postgraduate School Monterey Calif HYDRAULIC RAM PRESSURE MEASUREMENTS M S Thesis Clifford Milton Holm Dec 1974 51 p refs (AD-A004241) Avail NTIS CSCL 01/3 Hydraulic ram concerns the dynamic loads and catastrophic failure of liquid-filled fuel tanks impacted by highspeed projectiles Hydraulic ram is divided into two phases the shock phase and the drag phase Analytic models have been proposed for the shock phase by Yurkovich and for the drag phase by Lundstrom An attempt was made to correlate these theoretical pressure predictions with experimental data obtained from 0222 caliber projectiles impacting a small water-filled tank This comparison showed reasonable correlation but indicates that more work must be done to permit predictions of hydraulic ram pressures accurate enough for the purpose of fuel cell design GRA N75-27008*# National Aeronautics and Space Administration Ames Research Center Moffett Field Calif ACOUSTIC CHARACTERISTICS OF A LARGE SCALE WIND-TUNNEL MODEL OF A JET FLAP AIRCRAFT Michael D Falarski Thomas N Aiken and Kiyoshi Aoyagi Washington Jul 1975 36 p re's Prepared in cooperation with Army Air Mobility R and D Lab Moffett Field Calif (NASA-TM-X-3263 A-5923) Avail NTIS HC $3 75 CSCL 20A The expandmg-duct jet flap (EJF) concept is studied to determine STOL performance in turbofan-powered aircraft The EJF is used to solve the problem of ducting the required volume of air into the wing by providing an expanding cavity between the upper and lower surfaces of the flap The results are presented of an investigation of the acoustic characteristics of the EJF concept on a large-scale aircraft model powered by JT15D engines The noise of the EJF is generated by acoustic dipoles as shown by the sixth power dependence of the noise on jet velocity These sources result from the interaction of the flow turbulence with flap of internal and external surfaces and the trailing edges Increasing the trailing edge jet from 70 percent span to 100 percent span increased the noise 2 db for the equivalent nozzle area Blowing at the knee of the flap rather 415 N75-27015 than the trailing edge reduced the noise 5 to 10 db by displacing the jet from the trailing edge and providing shielding from high-frequency noise Deflecting the flap and varying the angle of attack modified the directivity of the underwmg noise but did not affect the peak noise A forward speed of 33 5 m/sec (110 ft/sec) reduced the dipole noise less than 1 db Author N75-27015*# National Aeronautics and Space Administration Flight Research Center, Edwards, Calif FLIGHT EVALUATION OF THE M2-F3 LIFTING BODY HANDLING QUALITIES AT MACH NUMBERS FROM 030 TO 1 61 Robert W Kempel. William H Dana, and Alex G Sim Washington Jul 1975 43 p refs (NASA-TN-D-8027. H-852) Avail NTIS HC $375 CSCL 01C Percentage distributions of 423 pilot ratings obtained from 27 flights are used to indicate the general level of handling qualities of the M2-F3 lifting body Percentage distributions are compared on the basis of longitudinal and lateral-directional handling qualities, control system, control system status, and piloting task Ratings of longitudinal handling qualities at low speed were slightly better than those for transonic and supersonic speed The ratings of lateral-directional handling qualities were unaffected by speed and configuration Specific handling qualities problems are discussed in detail, and comparisons are made with pertinent handling qualities criteria Author N75-27021# ARO, Inc Arnold Air Force Station Tenn EVALUATION OF A WEDGE ON A FORCE BALANCE AS A FLOW ANGLE PROBE Final Report H Maxwell and W Luchuk AEDC Feb 1975 68 p refs (AD-A004765 AEDC-TR-74-110 ARO-PWT-TR-74-88) Avail NTIS CSCL 20/4 A wedge wing on a force balance designed for use at Mach numbers 1 6 and 2 0 has been evaluated as a continuously mov- ing flow angle probe and calibrated in the range of Mach numbers from 0 6 to 1 3 Moving at standard speeds of the Captive Trajec- tory System (CIS) it has proved to be accurate and repeatable when operating in the three translational modes and the roll mode Performance is also reported in the pitch and yaw motions An extensive survey made at Mach number 0 6 shows the flow direction in the 4 tunnels used to be upward and toward the north wall with maximum components of 0 58 deg in pitch and 052degmyaw GRA N75-272230 Ill Research Inst Chicago III ANALYSIS. TEST AND EVALUATION SUPPORT TO THE USAF ADVANCED LANDING SYSTEM PROGRAM VOLUME 1 PROGRAM DESCRIPTION AND RESULTS Final Report. Jan 1972 - May 1974 A E Bnndley L C Calhoun T N Patton and L Valcik Aug 1974 301 p refs (Contract F33615-72-C-1024) (AD-A004419 AFFDL-TR-74-62-Vol-1) Avail NTIS CSCL 17/7 The report describes the efforts undertaken by IITRI in support of USAF s microwave landing system concept validation program It is concluded that the doppler guidance technique is conceptually sound but that considerable work is required to improve the implementation of the technique fundamental research in the area of multipath reflections is strongly recommended GRA N75-27224# III Research Inst Chicago III ANALYSIS. TEST AND EVALUATION SUPPORT TO THE USAF ADVANCED LANDING SYSTEM PROGRAM VOLUME 2 INDEX OF APPROACHES Final Report. Jan 1972 - May 1974 A E Bnndley L C Calhoun T N Patton and L Valcik Aug 1974 73 p refs (Contract F33615-72-C-1024) (AD-A004420 AFFDL-TR-74-62-Vol-2) Avail NTIS CSCL 17/7 Volume II is an index of the approaches flown during the MLS Concept Validation Program Part I lists the approaches in the order that they were flown it also contains information on the magnetic storage location of reduced data An explanation of the terms used is given as is a code for the notes used on the index of data Data from these approaches are plotted and contained in Volume III Part II is a listing of the approaches after sorting The sorting brings together similar approaches for comparison purposes GRA N75-27225# III Research Inst Chicago III ANALYSIS. TEST AND EVALUATION SUPPORT TO THE USAF ADVANCED LANDING SYSTEM PROGRAM VOLUME 3. PART 1 DOPPLER MLS GUIDANCE ERROR DATA (DOTS TRACKING SYSTEM) Final Report. Jan 1972 - May 1974 A E Bnndley L C Calhoun T N Patton and L Valcik Aug 1974 275 p (Contract F33615-72-C-1024) (AD-A004421, AFFDL-TR-74-62-Vol-3-Pt-1) Avail NTIS CSCL 17/7 Volume III Part I contains guidance error data for the Doppler MLS computed from the Digital Optical Tracking System (DOTS) information Separate plots are included for the azimuth system and the elevation system Volume III Parts 1. 2, and 3 contain the data used in determining the findings presented in Volume I GRA N75-27226# IIT Research Inst, Chicago, III ANALYSIS. TEST AND EVALUATION SUPPORT TO THE USAF ADVANCED LANDING SYSTEM PROGRAM VOLUME 3, PART 2 DOPPLER MLS GUIDANCE ERROR DATA (M-33 TRACKING SYSTEM. FLIGHTS 22 JUNE 1973 TO 10 SEPTEMBER 1974) Final Report, Jan 1972 - May 1974 A E Bnndley L C Calhoun T N Patton and L Valcik Aug 1974 323 p (Contract F33615-72-C-1024) (AD-A004422 AFFDL-TR-74-62-Vol-3-Pt-2) Avail NTIS CSCL 17/7 N75-27227# IIT Research Inst Chicago, III ANALYSIS, TEST AND EVALUATION SUPPORT TO THE USAF ADVANCED LANDING SYSTEM PROGRAM VOLUME 3, PART 3 DOPPLER MLS GUIDANCE ERROR DATA (M-33 TRACKING SYSTEM, FLIGHTS 12 SEPTEMBER 1973 TO 29 JANUARY 1974) Final Report. Jan 1972 - May 1974 A E Brmdley L C Calhoun T N Patton and L Valcik Aug 1974 283 p (Contract F33615-72-C-1024) (AD-A004423 AFFDL-TR-74-62-Vol-3-Pt-3) Avail NTIS CSCL 17/7 N75-27244 British Library Lending Div Boston Spa (England) ELECTRIC ENERGY AND NOISE G Pleeck 14 Feb 1975 21 p refs Transl into ENGLISH from French report Presented at 9th World Energy Conf Detroit, 1974 (BLL-CE-Trans-6550-(902209» Avail British Library Lending Div Boston Spa, Engl 3 BLL photocopy coupons Definitions measurements characteristics criteria propaga- tion limiting levels and reduction methods of noise are discussed Some typical power station equipment is considered such as gas reducing valves, steam venting fans, motors turboalternators transformers turbojets. and high voltage lines The trend to incorporate some acoustic absorption materials in the architecture of machine rooms in Belgium is reviewed Ideas concerning the necessity of preliminary acoustical engineering studies for a new installation are also presented JAM N75-27334*# National Aeronautics and Space Administration Langley Research Center Langley Station. Va 416 INSTRUMENTATION FOR MEASURING AIRCRAFT NOISE AND SONIC BOOM Patent Application Allan J Zukerwar inventor (to NASA) (Old Dominion Univ ) Filed 1 Jul 1975 17 p (Contract NAS1-11707) (NASA-Case-LAR-11476-1 US-Patent-Appl-SN-592159) Avail NTIS HCS325 CSCL 148 Improvements in instrumentation suitable for measuring aircraft noise and sonic booms are reported A converter produces an electric current proportional to the sound pressure level at a condenser microphone The electric current is transmitted over a cable and amplified by a zero drive amplifier The converter consists of a local oscillator a dual gate field effect transistor (FET) mixer and a voltage regulator/impedance translator The local oscillator generates a earner voltage that is applied to one of the gates of the FET mixer The FET mixer mixes the microphone signal with the carrier to produce an electrical current at the frequency of vibration of the microphone diaphragm The voltage regulator/impedance translator regulates the voltage of the local oscillator and mixer stages, eliminates the carrier at the output and provides a low output impedance at the cable terminals The improvements include automatic tuning compensa- tion against changes in static microphone capacitance and means for providing a remote electrical calibration capability NASA N75-27421*# National Aeronautics and Space Administration Lewis Research Center Cleveland Ohio ANALYSIS OF THE EFFECTS ON LIFE OF LEADING-EDGE HOLES IN AN AIRFOIL SUBJECTED TO ARBITRARY SPANWISE AND CHORDWISE TEMPERATURE DISTRIBU- TIONS Albert Kaufman Washington Jul 1975 17 p refs (NASA-TM-X-3257 E-8277) Avail NTIS HC $3 25 CSCL 01C The effects of temperature gradients cooling-hole rim and bulk metal temperatures and mechanical stress were investigated by using a finite-element structural analysis of a symmetrical airfoil with and without leading-edge holes The results indicate that leading-edge film cooling is beneficial when large chordwise temperature gradients exist and if the cooling-hole rim tempera- tures are above the bulk metal temperature The effects of film cooling at other locafons on the airfoil were not considered and the relative merits of convection or film cooling at the leading edge in terms of allowable turbine inlet temperature or coolant flow requirements were not evaluated Author N75-27422*# National Aeronautics and Space Administration Ames Research Center Moffett Field Calif ANALYTICAL MODELING REQUIREMENTS FOR TILTING PROPROTOR AIRCRAFT DYNAMICS Wayne Johnson Washington Jul 1975 59 p refs Prepared in cooperation with Army Air Mobility R and D Lab Moffett Field Calif (NASA-TN-D-8013 A-5698) Avail NTIS HCS425 CSCL 01A Proprotor and cantilever wing aeroelastic behavior is applied to a gimballed rotor and a hmgeless rotor to develop an analytical model for prediction of tilting proprotor aircraft dynamics Particular attention is given to the influence of coupled flap/lag bending modes the influence of rotor blade torsion degrees of freedom on proprotor dynamics and to a constant coefficient approxima- tion representing the dynamics in nonaxial flow through the rotor The following are also examined the number of blade bending and torsion modes required the influence of the rotor aerodynamic model the influence of the blade trim bending deflection the importance of the rotor rotational speed degree of freedom and the effect of the wing aerodynamic forces The origin of the significant influence of the blade pitch motion on the proprotor dynamics is discussed Author N75-27590# Joint Publications Research Service. Arlington. Va HIGH-ALTITUDE AIRCRAFT AND THE STRATOSPHERE N75-27949 I L Karol 8 Jul 1975 53 p refs Trans) into ENGLISH from the book Vysotnyye Samolety i Stratosfera Moscow. Gidrometeoizdat 1974 p 1-49 (JPRS-65171) Avail NTIS HCS425 Possible changes in the composition of the stratosphere as a result of the effect exerted on it by the discharge of combustion products from engines of high-altitude aircraft were studied taking into account predictions of the development of supersonic transport aircraft in the 1980 s Investigations of photochemical reactions between atmospheric gases the exhaust of aircraft and planetary distributions of the content of photochemically active small impurities in the stratosphere (especially ozone) were also considered N75-27855*# National Aeronautics and Space Administration Langley Research Center Langley Station Va RADIATED NOISE FROM AN EXTERNALLY BLOWN FLAP N N Reddy and J C Yu (George Washington Univ ) Washington Jul 1975 36 p refs (NASA-TN-D-7908 L-9895) Avail NTIS HC S3 75 CSCL 20A The far field noise from subsonic jet impingement on a wing-flap with a 45 deg bend was experimentally investigated The test parameters are jet Mach number and flap length For long flaps the primary source mechanisms are found to be turbulent mixing and flow impingement For short flaps the interaction of turbulent flow with the flap trailing edge appears to strongly influence the radiated noise Author N75-27949*# Scientific Translation Service. Santa Barbara, Calif ORGANIZING CENTRALIZED AIRCRAFT COMPONENT OVERHAUL S N Malkov Washington NASA Jul 1975 235 p refs Transl into ENGLISH from the book "Organizatsiya Tsentrahzovan- nogo Remonta Agregatov Samoletov" Moscow Transport Press 1974 p 1-180 (Contract NASw-2483) (NASA-TT-F-16266) Avail NTIS HC $7 50 CSCL 05A Preparation of a stable production base and rational organiza- tion of centralized component overhaul processes are examined Methods are presented for determining overhaul requirements, optimizing centralized production objects and locations, planning the production program introducing standardized technology, and fully mechanized flow lines for group overhaul of aircraft components Author 417 SUBJECT I N D E X AERONAUTICAL ENGINEERING/4 Special Bibliography (Suppl 62) Typical Subject Index Listing OCTOBER 1975 CYCLIC LOADS -Low cycle high temperature fatigue in aircraft ]et engines: conference proceedings- [AGABD-CP-155] N75-10"487 TITLE REPORT NUMBER The title is used to provide a description of the subject matter when the title is insufficiently descriptive of the document content a title extension is added separated from the title by three hyphens The NASA or AIAA accession number is included m each entry to assist the user in locating the abstract m the abstract section of this supplement If applicable a report number is also included as an aid in identifying the document 1-7 AIRCRAFT Investigation of the A-7 hook point attachment bolt loosening problem [AD-A004256] H75-25933 ABLATION Heat and mass transfer during high-enthalpy gas flow in aircraft and rocket engine flow passages A75-3807U ACCELEROHETESS Regional fatigue environment study for commuter airlines safe wing life [SAE PAPER 750512] A75-36655 ACCIDENT PREVEflrlOH Aerodynamic spoiler for preventing airplane stall/spin type accidents [AD-A006995] N75-2589H ACOUSTIC IHSTA0ILITY The acoustic response of a nozzle flow to an externally applied low frequency pressure field A75-38601 ACOUSTIC MEASUREMENTS Acoustic effects of rotor-wake interaction during low-power descent A75-383M7 Electric energy and noise emphasizing noise reduction [ BLL-CE-TBANS-6550- (9022.09) ] N75-272UU Instrumentat ion for measuring aircraft noise and sonic boon [ N A S A - C A S B - L A R - 1 11476-1 ] H75-2733U ACOUSTIC PROPERTIES Acoustic characteristics of a large scale wind- tunnel model of a ]et f l ap aircraft [ N A S A - T M - X - 3 2 6 3 ] N75-27008 ACOUSTIC SIMULATION Hybr id nonstationary noise simulator of the aircraf t overflight type [ O N E R A , TP NO. 1975-16] A75-37905 ACTUATORS Flight control actuator system development for P-0 aircraft [ A D - A O O U 8 5 3 ] H75-25962 ADAPTIVE CONTROL Digital adaptive f l ight control design using single stage model following indices A75-37135 AERIAL EIPLOSIOHS Theoretical predictions of thermal explosions. Part 1: A mathematical model of a bomb in a fire [REPT-623-PT-1 ] N75-26152 AERODYHABIC BALANCE Evaluation of a wedge on a force balance as a flow angle probe [ AD-A0014765] H75-27021 AERODTNAHIC CHARACTERISTICS Optimization method for a generalized class of functional of several variables, and its application to problems involving the determination of the shape of three-dimensional bodies with optimal aerodynamic characteristics A75-36166 Design of low-speed airfoils by numerical optimization [SAE PAPER 75052" ] A75-3666U Aviation in undulating flow - The Dolphin principle, its technical implementation, and its application in aviation A75-368«9 Aerodynamic analysis of helicopter configurations A75-37599 Experimental study of the influence of large blade aspect ratios on axial compressor stage aerodynamic characteristics A75-3806U Hechanisav of generating a normal force by a beat of the wings A75-38136 LTA aerodynamic data revisited [AIAA PAPER 75-951] A75-38550 Aerodynamic characteristics of an axisymmetric body undergoing a uniform pitching motion [AD-A003859] N75-25879 Aerodynamic analysis of a general purpose tow target [AD-A003197] N75-25881 Reynolds number effects on the boattail characteristics of a simulated nacelle at a Hach number of 0.8 [AD-AOOH803] N75-2588K Air launch characteristics of the MQM-7UC target drone from DC-130A airplane [AD-A0014190] N75-25892 An experimental investigation of the effect of a fuselage on wing characteristics [AD-A003955] N75-25921 Application of rotorcraft flight simulation program (C81) to predict rotor performance and bending moments for a model four-bladed articulated rotor system [AD-A001015] N75-2593U AERODYHABIC COEFFICIENTS An analytical and experimental evaluation of airfoil sections for helicopter rotor application A75-38319 AERODTNAHIC CONFIGORATIOSS Flow about a conic wing and the optimal configuration of the wing at hypersonic velocities A75-36099 A simplified approach to generalized helicopter configuration modeling and the prediction of fuselage surface pressures A75-38351 Aerodynamic analysis of a general purpose tow target [AD-A0031»97] N75-25881 The finite element method in low speed aerodynamics [NASA-CR-1U3190] N75-26972 Potential flow about three dimensional streamlined lifting configurations, with application to wings and rotors [AD-A003697] N75-26979 AERODYNAHIC DRAG Drag analysis methods for light aircraft [ASAE PAPER 750526] A75-36665 A-1 AERODTBAHIC FORCES SUBJECT IIDEI Sotorcraft parasite drag; Proceedings of the Thirty-first Annua l National Forum, Washington, D.C. , Bay 11, 15, 1975 A75-37593 A general review of helicopter rotor hub drag data A75-37591 The relationship between rotorcraft drag and stability and control A75-37597 Prediction of rotorcraft drag A75-37598 Helicopter parasite drag bibliography A75-37601 A second approximation to the induced drag of a rotor in forward flight A75-383I12 Wasted fuel - Another reason for drag reduction in helicopters A75-38352 Cost benefit evaluation of helicopter parasite drag reductions A75-38355 A comprehensive plan for helicopter drag reduction A75-38356 Steady and oscillatory, subsonic and supersonic, aerodynamic pressure and generalized forces for complex aircraft configurations and applications to flutter [NASA-CR-112983] N75-25871 ABBODYNABIC FORCES H A S P A flight control concepts High Altitude Superpressured Powered Aerostat [ A I A A P A P E R 75-9142] A75-37015 Airships in gusts - Apprehensions and assurance [ A I A A PAPER 75-950] A75-37021 Aircraft wake turbulence minimization by aerodynamic means A75-37150 Aerodynamic analysis of helicopter configurations A75-37599 Aircraf t loading spectra emphasizing maneuvering and gust loads A75-37823 Aerodynamic effects of vortex suppressors [AD-A003750] N75-25875 Evaluation of a wedge on a force balance as a f low angle probe [AD-A001765] N75-27021 AEEODIHABIC HEATING Heat exchange in the hypersonic flow of a rarefied gas past a blunt wedge A75-35913 AERODYNABIC INTEBFEEEBCE Performance of a sliding window detector in a high-interference air t raffic environment A75-37136 Effects of parasite drag on rotor performance and dynamic response A75-38353 AERODTHABIC LOADS Flutter of a panel supported on an elastic foundation A75-36215 Steady and oscillatory, subsonic and supersonic, aerodynamic pressure and generalized forces for complex aircraft configurations and applications to flutter [NASA-CR-112983] N75-25871 Theoretical prediction of airloads on thin delta wings in incompressible flow [ A D - A O O U 6 5 U ] N75-25891 AEBODTHABIC BOISE New directions in aircraft propulsor noise research [SAE PAPER 750515] A75-36657 Factors affect ing the noise f r o m small propeller driven aircraft [ S A E PAPER 750516] A75-36658 Theory of air f r a m e noise A75-37538 The acoustic response of a nozzle flow to an externally applied low frequency pressure field A75-38601 AEBODTHASIC STABILITY Flutter of a wing with nonlinear elastic characteristic A75-36191 Discussion of an aeromechanical gust alleviation* system to improve the ride comfort of light airplanes [SAE PAPER 7505111] A75-36675 High lift aircraft with improved stability, control, performance, and noise characteristics [NASA-CASE-LAB-11252-1] N75-25911 Analytical determination of aircraft spin modes [AD-AOOU798] N75-25931 AERODTHABIC STALLING Some ideas of vortex lift [SAE PAPER 750517] A75-36676 Dynamic stall characteristics of an oscillating airfoil in a harmonically varying freestream velocity N75-25863 Experimental studies of flow separation and stalling on a two-dimensional airfoil at low speeds [NASA-CR-2560] N75-26970 AEBOBLASTICITY Flutter of a wing with nonlinear elastic characteristic A75-36191 Beasurements on an isolated wing, using an aeroelastic model A75-37821 Trimming dual control rotors for optimum performance A75-38313 Effects of parasite drag on rotor performance and dynamic response A75-38353 AEROSPACE EBGIHEERIHG Israel Annual Conference on Aviation and Astronautics, 17th, Tel Aviv and Haifa, Israel, Bay 21, 22, 1975, Proceedings A75-37105 AFTEBBOBHIHG Turbofan compressor dynamics during afterburner transients [NASA-TM-X-71711 ] N75-25911 AIB CARGO Inventory of freight transportation in the Southwest. Part 3: Air freight service in the Dallas-Fort Worth area [PB-239820/1] N75-26987 AIB COOLING Optimizing aircraft gas turbine blade air cooling systems. II Therraodynamic analysis 175-38067 AIB FLOI A second approximation to the induced drag of a rotor in forward flight A75-38312 AIB INTAKES Calculation of flow field around air intake operating at zero forward speed by the distributed source-sink method /2-D case/ 475-38077 AIB LAUNCHING Air launch characteristics of the BQB-71C target drone from DC-130A airplane [AD-A001190] N75-25892 AIB NAVIGATION Development of navigation systems for advanced commercial transports A75-36368 Commercial developments'in airborne VLF navigation [SAE PAPER 750518] A75-36660 Omega Symposium, 2nd, Washington, D.C., November 5-7, 1971, Proceedings A75-36951 Omega signal coverage prediction A75-36952 Accuracy specifications for automatic Omega navigators A75-36953 Experimental Omega four freguency format extends lane ambiguity global search and rescue system A75-36951 A comprehensive experimental program for investigation of various Omega operational modes with selected data analysis results A75-36955 Omega navigation systems specification and performance measurement , A75-36956 SOBJECT INDEX AIBCBAFT COBTBOL Recent results on parametric analysis of differential Onega error A75-36959 state of experimentations and program of development of Differential OMEGA in Prance A75-36961 Alternative approaches to integrated airborne OMEGA/Inertial navigation A75-36962 Mix and. match - A hybrid Omega-Inertial airborne navigation system A75-36961 An empirical computed evaluation of composite Omega A75-36965 Plight test of AHN-99/V/2 Onega Navigation Set in F-1 aircraft A75-36966 Airborne ONS - A low cost alternate to INS Omega and Inertial Navigation Systems compared A75-36967 A technigue to improve the performance of a nonlinear filter with an application to satellite-aided aircraft navigation A75-37138 The cost-effectiveness of inertial navigation for civil aircraft A75-38261 AIB POLLUTION Technology for reducing aircraft engine pollution [ S A E P A P E R 750550] A75-36677 Methodology for certification of aircraft nuisances [ O N E R A , TP HO. 1975-1(8] A75-37900 High-alt i tude aircraft and the stratosphere [JPRS-65171] N75-27590 AIR TRAFFIC The dynamics of the civil aviation industry Book A75-36107 AIB TRAFFIC CONTROL Development of navigation systems for advanced commercial transports A75-36368 The promise of air safety collision avoidance systems A75-36101 Differential Omega in the air t ra f f ic control environment A75-36958 Performance of a sliding window detector in a high-interference air traffic environment A75-37136 Feasibility of real time simulation of airport/airside operations [ A D - A 0 0 6 9 9 6 ] N75-26991 AIR TRANSPORTATION European industry and civil air transport /28th Louis Bleriot Lecture/ A75-36718 A balloon transport system [ A I A A P A P E R 75-926] A75-37001 The Navy role in buoyant and semi-buoyant systems of the future LTA design [ A I A A P A P E R 75-937] A75-37011 Potential missions for advanced airships [ A I A A PAPER 75-916] A75-37019 Inventory of freight transportation in the Southwest. Part 3: Air freight service in the Dallas-Fort Worth area [PB-239820/U] N75-26987 AIRBORNE BQtllPBENT Commercial developments in airborne VLF navigation [ S A E PAPER 750518] A75-36660 Awacs - Boeing's radar patroller A75-36765 Alternative approaches to integrated airborne OHEGA/Inertial navigation A75-36962 Airborne Omega navigation system integration and test A75-36963 Mix and match - A hybrid Omega-Inertial airborne navigation system A75-36961 Flight test of ARN-99/V/2 Omega Navigation Set in F-1 aircraft A75-36966 Airborne ONS - A low cost alternate to INS Omega and Inertial Navigation Systems compared A75-36967 N75-25905 Spike, relays and aircraft electric systems A75-38726 AIBBOBNE/SPACEBOBNE COHFDTERS Future trends in flight control systems A75-38262 A universal flight director computer [AD-A003631] AIRCBAFT ACCIDENT INVESTIGATION Aircraft accident report: Air East, Inc. Beechcraft 99A, N125AE, Johnstown-Cambria County Airport, Johnstown, Pennsylvania, 6 January 1974 [PB-239891/5] N75-26982 Aircraft accident report. Brief format, D.S. Civil Aviation issue number 3 of 1971 accidents. File numbers: 1-0002 thru 1-0007, 1-0009 thru 1-0019, 1-0021 thru 1-0023, 1-0025 thru 1-0028, 3-1031, 3-1111, 3-1801 thru 3-2700 [PB-21036U/0] N75-26983 Aircraft accident report: New Jersey Air National Guard F106, serial number 59-00141, Piper PA-21-250, N6876P, midair collision near Saxis, Virginia, 11 October 1971 [PB-210250/1] N75-26981 Aircraft accident report: Aircraft Pool Leasing Corporation, Lockheed super constellation, L-1019H, N6917C, Miami, Florida, 15 December 1973 [PB-210120/6] N75-26985 Aircraft accident report: Saturn Airways Inc., Lockheed L-382, N11ST, Springfield, Illinois, 23 Bay 1971 [PB-210119/8] N75-26986 Annual review of aircraft accident data, DS general aviation, calendar year 1972 [PB-239608/3] H75-26988 Aircraft accident report: National Airlines, Incorporated, DC-10-10, N60NA, near Albuguerque, New Mexico, 3 November 1973 [PB-239889/9] N75-26989 Aircraft accident report: Iberia Lineas Aereas De Espana (Iberian Airlines) . McDonnell Douglas DC-10-30, EC CBN Logan International Airport, Boston, Massachusetts, 17 December 1973 [PB-239890/7] N75-26990 AIRCRAFT ACCIDENTS Aerodynamic spoiler for preventing airplane stall/spin type accidents [AD-A006995] N75-25891 AIBCBAFT ANTENNAS B-52G/H Protective Systems Test Range /PSTR/ --- antenna radiation pattern measurement A75-37671 &IBCBAFT BBAKES Wet runway aircraft control project F-1 rain tire project [AD-A001768] N75-25896 Design of aircraft wheels and brake systems [NASA-TT-F-15761] N75-25918 Friction and wear of carbon-graphite materials for high energy brakes [NASA-TN-D-8006] N75-26137 AIECBiFT CONFIGURATIONS Evaluation of advanced airship concepts [AIAA PAPER 75-930] A75-37007 Operational considerations of large rigid airships in military applications [AIAA PAPER 75-938] A75-37012 Wing-Tip-Winglet propulsion for Aerocrane-type hybrid lift vehicles [AIAA PAPER 75-911] A75-37017 Aerodynamic analysis of helicopter configurations A75-37599 Steady and oscillatory, subsonic and supersonic, aerodynamic pressure and generalized forces for complex aircraft configurations and applications to flutter [NASA-CR-112983] N75-25871 Engine/airf rame compatibility studies for supersonic cruise aircraft [ NASA-CR-132610-1 ] N75-25916 A computer program for fitting smooth surfaces to an aircraft configuration and other three dimensional geometries [NASA-TH-X-3206] N75-26693 AIRCRAFT COBTBOL Wind tunnel and flight development of spoilers for general aviation aircraft [SAE PAPEB 750523] A75-36663 An in-flight investigation of nonlinear roll control [SAE PAPEB 750528] A75-36666 i-3 AIRCRAFT DESIGN SUBJECT INDEX Autopilot for British Airways A75-37778 Future trends in flight control systems A75-38262 Wet runway aircraft control project F-1 rain tire project [AD-A001768] N75-25896 High lift aircraft with improved stability, control, performance, and noise characteristics [ N A S A - C A S E - L A R - 1 1252-1] N75-25911 Selection of sampling rate for digital control of aircrafts N75-25959 AIRCRAFT DESIGN Kawasaki C-1 - Japan 's raini-StarLifter A75-35899 Design of low-speed airfoils by numerical optimization [ S A E PAPER 750521] A75-36661 Drag analysis methods for light aircraft [ A S A E P A P E R 750526] A75-36665 Graphite composite materials applications in aircraft structures [ S A E P A P E R 750533] A75-36670 N A S A General Aviation Research overview - 1975 [ S A E P A P E R 750500] A75-36678 Handl ing and performance characteristics of swept-forward flying wing aircraft [ S A E P A P E R 750518] A75-36679 Aviation in undulating flow - The Dolphin principle, its technical implementation, and its application in aviation A75-36819 H A S P A design and flight test objectives High Alt i tude Superpressured Powered Aerostat [ A I A A P A P E R 75-921] A75-37002 Development and flight experience of a manned thermal airship f A I A A P A P E R 75-925] A75-37003 Evaluation of advanced airship concepts [ A I A A P A P E R 75-930] A75-37007 ' The Shell natural gas airship, and other L.T.A. activities by Aerospace Developments [ A I A A P A P E R 75-932] A75-37008 Structural design of a High-Altitude Superpressure Powered Aerostat [ A I A A PAPER 75-933] A75-37009 The Navy role in buoyant and semi-buoyant systems of the fu ture LTA design [ A I A A P A P E R 75-937] A75-37011 Computer aided airship design [ A I A A P A P E R 75-915] A75-37018 Airships in gusts - Apprehensions and assurance [ A I A A PAPER 75-950] A75-37021 Design fabrication and test of an F-11 composite overwing fairing A75-37310 Recent development and experience of an all fiberglass RP undercarriage for a STOL-aircraft A75-37311 Intuitive design applied to aircraft structural design A75-37125 The F-1U aircraft head up display A75-37700 The concept of trustworthiness in the safety of structures weight-optimal aircraft structural design A75-37799 A/A 17U-3 tow target reeling machine launcher system [AD-A001622] 1175-25882 High lift aircraft with improved stability, control, performance, and noise characteristics [NASA-CASE-LAR-11252-1] S75-25911 Aircraft design implications of opto-electronic systems N75-26787 A fuselage/tank structure study for actively cooled hypersonic cruise vehicles: Aircraft design evaluation [NASA-CH-132668] N75-26997 The effects of aircraft design on STOL ride quality [HASA-CR-113113] H75-27001 AIRCRAFT DETECTION Awacs - Boeing's radar patroller A75-36765 ilBCHAFT ENGINES Aircraft engine lube oil filtration study [SAE PAPER 750505] ' A75-36651 Low emission, water-tolerant combustor for a small, all-weather turboshaft gas turbine engine [SAE PAPER 750535] A75-36672 A second generation turbo-prop power plant [SAE PAPER 750536] A75-36673 Technology for reducing aircraft engine pollution [SAE PAPER 750550] A75-36677 Full authority electronic control application to military gas turbine engines A75-37616 Optimizing aircraft gas turbine blade air cooling systems. II Thermodynamic analysis A75-38067 Heat and mass transfer during high-enthalpy gas flow in aircraft and rocket engine flow passages A75-38071 Field tests of a laser Raman measurement system for aircraft engine exhaust emissions [AD-A003618] N75-259U9 AIRCRAFT EQUIPHENT Blindside connector selection for aircraft wiring A75-37711 Looping in a hydrogen cooling system A75-38370 Influence of solid state electrical distribution on aircraft power generation solid state power controller compatibility use on B-1 aircraft [AD-A003831] N75-26273 AIRCRAFT FDEL SYSTEMS Hydraulic ram pressure measurements fuel aircraft systems - impact damage [AD-A001241] N75-27005 AIRCRAFT FUELS Alternative fuels for aviation A75-36719 Evaluation of the overall fuel mass penalty of an aircraft system A75-36720 AIRCRAFT GOIDAHCE BADGE - Evaluating a helicopter approach guidance system A75-37300 Improvement of AN/TPQ-27 filter and control techniques [AD-A003878] N75-25903 AIRCRAFT HAZARDS Aircraft wake turbulence minimization by aerodynamic means A75-37150 AIRCRAFT HYDRAULIC SYSTEHS Aircraft hydraulic system pressure regulator stability A75-38076 Hydraulic ram pressure measurements fuel aircraft systems - impact damage [AD-A001211] N75-27005 AIRCRAFT INDUSTRY European industry and civil air transport /28th Louis Bleriot Lecture/ A75-36718 AIRCRAFT INSTRUBENTS Results of an investigation of two three-dimensional low-level flight systems A75-36992 Performance comparison of space stable and local level inertial platform mechanizations for a strategic aircraft application A75-37703 AIRCRAFT LANDING Microwave technology in the microwave landing system A75-36529 Instrument Landing System performance prediction A75-36530 Propeller modulation effects on a scanning-beam microwave landing system [SAE PAPER 750521] A75-36661 Flight mechanics and pilot evaluation of conventional landings [SAE PAPER 750529] A75-36667 Pilot problems in low visibility approach and landing A75-37189 Elastically retracting ACLS trunks Air Cushion Landing System A75-38052 AIRCRAFT HAINTEBASCE Aircraft engine lube oil filtration study [SAE PAPER 750505] A75-36651 SUBJECT IHDEI AIBFBABE HATEBIALS Technical diagnostics in aircraft naintenance A75-36818 Specific properties of high-strength and heat-resistant wrought a luminum alloys and the consideration of these properties in the maintenance of aircraft. II 475-36850 &IECRAPT BiSEUfERS Aircraft loading spectra emphasizing maneuvering and gust loads A75-37823 Sequential attack in aerial combat [AD-A001796] N75-25929 AIRCRAFT HODELS Heasurements on an isolated wing, using an aeroelastic model A75-37821 AIRCRAFT BOISE New directions in aircraft propulsor noise research [ S A E P A P E R 750515] A75-36657 Factors affect ing the noise f rom small propeller driven aircraft [ S A E PAPEB 750516] A75-36658 Ducted propulsors - Progress in the United Kingdom [ S A E PAPER 7505314] A75-36671 Methodology for certification of aircraft nuisances [ O N E R A , TP NO. 1975-18] A75-37900 Hybrid nonstationary noise simulator of the aircraft overflight type [ O N E R A , TP NO. 1975-16] A75-37905 Summary of results indicating the beneficial effects of rotor vortex modification A75-38315 A social survey to examine the variance of aircraft noise annoyance A75-38603 A method for predicting acoustically induced vibration in transport aircraft, appendix [AD-A001215] N75-25883 Instrumentation for measuring aircraft noise and sonic boom [NASA-CASE-LAR-11176-1] N75-27331 AIRCRAFT PERFORBAHCE Handling and performance characteristics of swept-forward flying wing aircraft [ S A E P A P E R 750518] A75-36679 Evaluation of the overall fuel mass penalty of an aircraft system A75-36720 The use of computers in fl ight testing A75-37779 Cockpit-system study YAK 10. A pilot opinion survey to the aircraft handl ing and system gualltles [DlR-FB-75-15] N75-25961 AIRCRAFT PILOTS Cockpit-system study YAK 10. A pilot opinion survey to the aircraft handling and system qualities [DLR-FB-75-15] N75-25961 AIRCRAFT PBODOCTIOH Kawasaki C-1 - J a p a n ' s mini-StarLifter A75-35899 AIRCRAFT RELIABILITY Regional fatigue environment study for commuter airlines safe wing life [ S A E PAPER 750512] A75-36655 The B-1 structural integrity program [ S A E P A P E R 750511] A75-36656 On-board test and monitoring of advanced weapon systems A75-37611 The concept of trustworthiness in the safety of structures weight-optimal aircraft structural design A75-37799 A STOL airworthiness investigation using a simulation of an augmentor wing transport, volume 2: Simulation data and analysis [NASA-TH-X-62396 ] N75-25917 AIRCRAFT SAFETY The promise of air safety collision avoidance systems A75-36101 AIRCRAFT STABILITY Discussion of an aeromechanical gust alleviation system to improve the ride comfort of light airplanes [ S A E P A P E R 750511] A75-36675 Synthesis of disturbance-rejection controllers for linear multivariable continuous-time systems application to hovering helicopter A75-37109 The relationship between ^otorcraft drag and stability and control A75-37597 Aircraft loading spectra emphasizing maneuvering and gust loads A75-37823 Static stability and aperiodic divergence in longitudinal flight A75-38579 AIRCRAFT STROCTOBES Damage resistance of high modulus aramid fiber composites in aircraft applications [SAE PAPER 750532) A75-36669 Graphite composite materials applications in aircraft structures [SAE PAPER 750533] A75-36670 Some practical considerations found in the use of solid film lubricants in aircraft systems A75-38122 Organizing centralized aircraft component overhaul [NASA-TT-F-16266] N75-27919 AIRCRAFT TIBES Wet runway aircraft control project F-1 rain tire project [AD-A001768] N75-25896 Design of aircraft wheels and brake systems [NASA-TT-F-15761] N75-25918 AIRCRAFT BAKES Aircraft wake turbulence minimization by aerodynamic means A75-37150 Exploratory flight investigation of aircraft response to the wing vortex wake generated by the augmentor wing jet STOL research aircraft [NASA-TM-X-62387] N75-26980 AIRFOIL PROFILES Hind tunnel and flight development of spoilers for general aviation aircraft [SAE PAPER 750523] A75-36663 Design of low-speed airfoils by numerical optimization [SAE PAPER 750521] A75-36661 Two dimensional, inviscid, transonic flowfield around a profile A75-37121 Viscous interaction with separation in transonic flow [ONEBA, TP NO. 1975-15] A75-37897 A state-of-the-art survey of two-dimensional airfoil data A75-38318 An analytical and experimental evaluation of airfoil sections for helicopter rotor application A75-38319 A tunnel spanning airfoil testing technique A75-38350 A study of the potential benefits of advanced airfoils for helicopter applications A75-38357 A review of design objectives for advanced helicopter rotor airfoils A75-38358 Detailed transonic flow field measurements about a supercritical airfoil section [NASA-TM-X-3211] N75-26975 AIRFOILS Drag analysis methods for light aircraft [ASAE PAPER 750526] A75-36665 Numerical solution of the Navier-Stokes eguations for arbitrary two-dimensional multi-element airfoils [NASA-CR-113038] N75-25871 Experimental studies of flow separation and stalling on a two-dimensional airfoil at low speeds [NASA-CH-2560] N75-26970 Analysis of the effects on life of leading-edge holes in an airfoil subjected to arbitrary spanwise and chordwise temperature distributions structural analysis [NASA-TB-X-3257] N75-27121 AIBFBABE HATERIALS The B-1 structural integrity program [SAE PAPER 750511] A75-36656 A-5 AIRFRABES SUBJECT IBDBX AIBFRABES Theory of air f r a m e noise A75-37538 Application of high temperature composites to an aircraft component [AD-A003516] N75-25925 AIELINE OPEBiTIOHS Autopilot for British Airways A75-37778 The cost-effectiveness of inertial navigation for civil aircraft A75-38261 AIRPORT P L A N N I N G Instrument Landing System performance prediction A75-36530 ilBPOBTS Feasibility of real time simulation of airport/airside operations [AD-A006996] N75-26991 AIRSHIPS Aviation in undulat ing flow - The Dolphin principle, its technical implementation, and its application in aviation A75-368U9 H A S P A design and flight test objectives High Altitude Superpressured Powered Aerostat [ A I A A P A P E R 75-921] A75-37002 Development and flight experience of a manned thermal airship [ A I A A PAPER 75-925] A75-37003 A non-polluting powerplant for large airships [ A I A A P A P E R 75-927] A75-37005 A feasibility study of a trans-ocean hybrid cargo airship operating in ground effect [ A I A A P A P E R 75-929] A75-37006 Evaluation of advanced airship concepts [ A I A A P A P E R 75-930] A75-37007 The Shell natural gas airship, and other L.T.A. activities by Aerospace Developments [ A I A A PAPER 75-932] A75-37008 Structural design of a High-Altitude Superpressure Powered Aerostat [ A I A A P A P E R 75-933] A75-37009 The Navy role in buoyant and semi-buoyant systems of the future LTA design [ A I A A PAPER 75-937] A75-37011 Operational considerations of large rigid airships in military applications [ A I A A P A P E R 75-938] A75-37012 H A S P A flight control concepts High Altitude Superpressured Powered Aerostat [ A I A A P A P E R 75-912] A75-37015 Wing-Tip-Winglet propulsion for Aerocrane-type hybrid lift vehicles [ A I A A P A P E R 75-9114] A75-37017 Computer aided airship design [ A I A A P A P E R 75-915] A75-37018 Potential missions for advanced airships [ A I A A P A P E R 75-916] A75-37019 A strategy for getting LTA systems airborne [ A I A A P A P E R 75-919] A75-37020 Airships in gusts - Apprehensions and assurance [ A I A A P A P E R 75-950] A75-37021 LTA aerodynamic data revisited [ A I A A P A P E R 75-951] A75-38550 ALGORITHMS Evaluation of real-time algorithms for Omega propagation prediction A75-36973 ALDBINOB ALLOYS Specific properties of high-strength and heat-resistant wrough t a l u m i n u m alloys and the consideration of these properties in the maintenance of aircraft , II A75-36850 Residual stresses caused by variable service loads in notches and their significance for the applicability of the linear damage accumulation hypothesis in Al alloys A75-37777 ANGLE OP ATTACK Lamina r boundary layer in symmetry plane of blunt-nosed body A75-36211 An investigation of the departure modes of a F-1D aircraft f rom a steady sideslip flight condition [AD-A001795] 875-25928 ANGDLAB VELOCITY The supersonic rotor for helicopters A75-38316 A N T E H N A RADIATION PATTERNS B-52G/H Protective Systems Test Bange /PSTB/ antenna radiation pattern measurement A75-37671 ANTIFRICTION BBABIHGS Ceramic airframe bearings solid lubricant selection tests [ASLE PBEPRINT 75AM-7A-3] A75-37096 Application of high frequency resonance technigues for bearing diagnostics in helicopter gearboxes [AD-A001011] N75-25936 APPROACH Three methods of presenting flight vector information in a head-up display during simulated STOL approaches [NASA-TH-X-3273] B75-26996 APPROACH CONTBOL Microwave technology in the microwave landing system A75-36529 MADGE - Evaluating a helicopter approach guidance system A75-37300 Pilot problems in low visibility approach and landing A75-37189 ABEA NAVIGATION An evaluation of differential Omega for general aviation area navigation A75-36960 ATHOSPHEBIC TOBBULEHCE Regional fatigue environment study for commuter airlines safe wing life [SAE PAPEB 750512] A75-36655 Airships in gusts - Apprehensions and assurance [AIAA PAPER 75-950] A75-37021 Problems of flight in turbulence . [NASA-TT-F-16101] N75-26977 ADTOBATIC CONTBOL Accuracy specifications for automatic Omega navigators A75-36953 AOTOHATIC FLIGHT COHTBOL Results of an investigation of two three-dimensional low-level flight systems A75-36992 Future trends in flight control systems A75-38262 AOTOSATIC PILOTS Autopilot for British Airways A75-37778 Investigation of self-oscillations of an autopilot mount A75-38111 AVI08ICS A multifunction radar for helicopter applications A75-37638 On-board test and monitoring of advanced weapon systems A75-37611 Terrain following evaluation simulation B-1 aircraft avionics A75-37617 AXIAL COBPBESSIO8 LOADS Minimum weight design of fuselage type stiffened circular cylindrical shells subject to uniform axial compression [AD-A001112] N75-25927 AXIAL FLOB TOBBINES Design estimate of cascade performance A75-36291 AXISYBBETBIC BODIES Investigation of the turbulent properties of the wake behind self propelled, axisymmetric bodies N75-25865 Aerodynamic characteristics of an axisymmetric body undergoing a uniform pitching motion [AD-A003859] N75-25879 A study of the flow around plane and axially symmetrical bodies with a separated shock wave by a flow at low supersonic speed [ AD-A0011412] N75-25887 AXISYaBETBIC FLOU Hodograph method for axisymmetric transonic gas flows A75-35967 A-6 SOBJECT IRDEI B B-1 AIRCRAFT The B-1 structural integrity program [SAE PAPER 75051U] A75-36656 On-board test and monitoring of advanced weapon systems A75-37640 Terrain following evaluation simulation B-1 aircraft avionics A75-376H7 Performance comparison of space stable and local level inertial platform mechanizations for a strategic aircraft application A75-37703 Inf luence of solid state electrical distribution on aircraft power generation solid state power controller compatibility use on B-1 aircraft [AD-A003830] B75-26273 B-52 AIRCBAPT B-52G/H Protective systems Test Bange /PSTB/ antenna radiation pattern measurement A75-3767H BALLISTIC TBAJECTORIES Aircraf t fuel tank vulnerability to hydraulic ram: Modificat ion of the Northrop finite element computer code BR-1 to include fluid-structure interaction: Theory and users manual for BR-1 HR [AD-A003171] K7S-25922 BALLOOH PLIGHT A balloon transport system [ A I A A P A P E R 75-926] A75-3700M BEECHCRAFT AIRCRAFT Ai rc ra f t accident report: Air East r Inc. Beechcraft 99A, N125AE, Johnstown-Cambria County Airport , Johns town, Pennsylvania , 6 January 1971 [PB-239891/5] N7S-26982 BENDING BOHEHTS Application of rotorcraft flight simulation program (C81) to predict rotor performance and bending moments for a model four-bladed articulated rotor system [ A D - A O O t 0 1 5 ] 075-25931 BIBLIOGRAPHIES N A S A General Aviation Research overview - 1975 [ S A E PAPER 750500] A75-36678 Helicopter parasite drag bibliography A75-37601 BINARY DATA Binary phase locked loops for Omega receivers A75-36968 BLDFF BODIES A comprehensive plan for helicopter drag reduction A75-38356 BLUNT BODIES Analytic investigation of hypersonic flow around blunt bodies A75-36163 Laminar boundary layer in symmetry plane of blunt-nosed body A75-362i»1 Boundary layer transition on blunt bodies [ A D - A O O U 8 2 6 ] B75-25877 BOATTAILS Reynolds number effects on the boattail characteristics of a simulated nacelle at a Hach number of 0.8 [ A D - A O O U 8 0 3 ] S75-2588U BODIES OF RE70LUTIOB Hodograph method for ajtisymmetnc transonic gas flows A75-35967 The resistance of bodies of revolution at transonic flow velocities A75-35968 A three-dimensional method for the calculation of flow in tnrbomachines using finite elements on a blade-to-blade surface of revolution Book A75-36899 BODT-SING CONFIGURATIONS An experimental investigation of the effect of a fuselage on wing characteristics [AD-A003955] N75-25921 BOEING AIRCRAFT Awacs - Boeing's radar patroller A75-36765 BOEING 707 AIRCRAFT The measurement of the Boeing 707 trailing vortex system using the tower fly-by technigue [AD-A0083811] H75-25868 BOLTS Investigation of the A-7 hook point attachment bolt loosening problem [AD-A004256] B75-25933 BOBBER AIRCRAFT B-1 unique signal train generation application study [AD-A003682] N75-2699

Aeronautical Engineering: A special bibliography with indexes, supplement 62

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