Operational experience with a powered-lift STOL aircraft

The experience gained in over four years of STOL operations with the augmentor wing research aircraft and the background of operation of other STOL powered-lift aircraft indicate that the use and percent of lift achieved by powered lift have significant effects on the operational characteristics of STOL aircraft and, therefore, on the performance that can be achieved. A brief description of the augmentor wing including the means by which it achieves its powered lift is presented. Specific problem areas relating to the control of longitudinal flight path are discussed as well as the consequences these might have on the design and operation of this class of aircraft. Particular emphasis is given to the approach and landing phase of flight where the consequences of the powered lift are most pronounced, and the resultant characteristics most different from those of conventional aircraft

Flight-path and airspeed control during landing approach for powered-lift aircraft

Manual control of flight path and airspeed during landing approach has been investigated for powered-lift transport aircraft. An analysis was conducted to identify the behavior of the aircraft which would be potentially significant to the pilot controlling flight path and airspeed during the approach. The response characteristics found to describe the aircraft behavior were (1) the initial flight-path response and flight-path overshoot for a step change in thrust, (2) the steady-state coupling of flight path and airspeed for a step change in thrust, and (3) the sensitivity of airspeed to changes in pitch attitude. The significance of these response characteristics was evaluated by pilots on a large-motion, ground-based simulator at Ames Research Center. Coupling between flight path and airspeed was considered by the pilot to be the dominant influence on handling qualities for the approach task. Results are compared with data obtained from flight tests of three existing powered-lift V/STOL aircraft

Flight evaluation of configuration management system concepts during transition to the landing approach for a powered-lift STOL aircraft

Flight experiments were conducted to evaluate two control concepts for configuration management during the transition to landing approach for a powered-lift STOL aircraft. NASA Ames' augmentor wing research aircraft was used in the program. Transitions from nominal level-flight configurations at terminal area pattern speeds were conducted along straight and curved descending flightpaths. Stabilization and command augmentation for attitude and airspeed control were used in conjunction with a three-cue flight director that presented commands for pitch, roll, and throttle controls. A prototype microwave system provided landing guidance. Results of these flight experiments indicate that these configuration management concepts permit the successful performance of transitions and approaches along curved paths by powered-lift STOL aircraft. Flight director guidance was essential to accomplish the task

A simulator and flight study of yaw coupling in turning maneuvers of large transport aircraft

Piloted simulator study of yaw coupling in turning maneuvers of supersonic transport compared with flight test data on large variable stability jet transpor

A Flight Investigation of the STOL Characteristics of an Augmented Jet Flap STOL Research Aircraft

The flight test program objectives are: (1) To determine the in-flight aerodynamic, performance, and handling qualities of a jet STOL aircraft incorporating the augmented jet flap concept; (2) to compare the results obtained in flight with characteristics predicted from wind tunnel and simulator test results; (3) to contribute to the development of criteria for design and operation of jet STOL transport aircraft; and (4) to provide a jet STOL transport aircraft for STOL systems research and development. Results obtained during the first 8 months of proof-of-concept flight testing of the aircraft in STOL configurations are reported. Included are a brief description of the aircraft, fan-jet engines, and systems; a discussion of the aerodynamic, stability and control, and STOL performance; and pilot opinion of the handling qualities and operational characteristics

Flight-test evaluation of STOL control and flight director concepts in a powered-lift aircraft flying curved decelerating approaches

Flight tests were carried out to assess the feasibility of piloted steep curved, and decelerating approach profiles in powered lift STOL aircraft. Several STOL control concepts representative of a variety of aircraft were evaluated in conjunction with suitably designed flight directions. The tests were carried out in a real navigation environment, employed special electronic cockpit displays, and included the development of the performance achieved and the control utilization involved in flying 180 deg turning, descending, and decelerating approach profiles to landing. The results suggest that such moderately complex piloted instrument approaches may indeed be feasible from a pilot acceptance point of view, given an acceptable navigation environment. Systems with the capability of those used in this experiment can provide the potential of achieving instrument operations on curved, descending, and decelerating landing approaches to weather minima corresponding to CTOL Category 2 criteria, while also providing a means of realizing more efficient operations during visual flight conditions

Flight experiments using the front-side control technique during piloted approach and landing in a powered lift STOL aircraft

The essential features of using pitch attitude for glidepath control in conjunction with longitudinal thrust modulation for speed control are described, using a simple linearized model for a powered-lift STOL aircraft operating on the backside of the drag curve and at a fixed setting of propulsive lift. It is shown that an automatic speed-hold system incorporating heave-damping augmentation can allow use of the front-side control technique with satisfactory handling qualities, and the results of previous flight investigations are reviewed. Manual control considerations, as they might be involved following failure of the automatic system, are emphasized. The influence of alternative cockpit controller configurations and flight-director display features were assessed for their effect on the control task, which consisted of a straight-in steep approach flown at constant speed in simulated instrument conditions

Flight investigation of methods for implementing noise-abatement landing approaches

Flight tests and simulation of steep noise reducing landing approaches with jet transpor

Flight evaluation of the STOL flare and landing during night operations

Simulated instrument approaches were made to Category 1 minimums followed by a visual landing on a 100 x 1700 ft STOL runway. Data were obtained for variations in the aircraft's flare response characteristics and control techniques and for different combinations of aircraft and runway lighting and a visual approach slope indication. With the complete aircraft and runway lighting and visual guidance no degradation in flying qualities or landing performance was observed compared to daylight operations. elimination of the touchdown zone floodlights or the aircraft landing lights led to somewhat greater pilot workload; however, the landing could still be accomplished successfully. Loss of both touchdown zone and aircraft landing lights led to a high workload situation and only a marginally adequate to inadequate landing capability

Near-Earth Asteroid Resources: Review and Analogue Study of Highly Siderophile Elements in Main-Group Pallasites

The potential for NEAs as targets for space resource utilization has been explored. Water and PGEs have been identified as resources with potential profitability in existing markets. Of the ~18,000 asteroids in the known NEA catalogue, seven and three are expected to be prospective for water and PGEs when accounting for size, resource concentration, and accessibility. Improved NEA discovery campaigns, with emphasis on spectroscopy, and advancements in space transportation and autonomous robotic technology are crucial to future success of NEA resource utilization. LA-ICP-MS was used to evaluate main-group pallasites (PMG) for PGE potential. Bulk metal concentrations of most PGEs are lower than in iron meteorites, making the associated parent body(ies) of the PMG suboptimal for resource utilization. Average subsolidus partition coefficients are 1 \u3c DT/K(Ir) \u3c DT/K(Pt) ≈ DT/K(Os) \u3c DT/K(Rh) \u3c DT/K(Ru) \u3c DT/K(Pd) and appear to be applicable to all instances of taenite/kamacite, regardless of parent body conditions