Results of static tests of a 1/4 scale model of the Boeing YC-14 powered-lift system

One quarter scale static ground tests of the Boeing YC-14 powered lift system were conducted for correlation with full scale test results. The 1/4 scale model utilized a JT-15D turbofan engine to represent the CF6-50D engine employed on the YC-14 advanced medium STOL transport prototype aircraft. The tests included evaluation of static turning performance, static surface pressure and temperature distributions, fluctuating loads, and accelerations of portions of the wing, flaps, and fuselage. Results are presented for the landing flap configuration over an appropriate range of fan pressure ratio as affected by several variables including ground height and vortex generator modifications. Static turning angles of the order of 60 deg were obtained. The highest surface pressures and temperatures were concentrated over the upper surface of the flaps in the region immediately aft of the upper surface blown nozzle

INVESTIGATION OF THE LOW-SUBSONIC STABILITY AND CONTROL CHARACTERISTICS OF A 0.34 -SCALE FREE-FLYING MODEL OF A MODIFIED HALF-CONE REENTRY VEHICLE

Low subsonic stability and control of a 0.34-scale free flying model of a half cone reentry vehicl

Space shuttle nonmetallic materials age life prediction

The chemiluminescence from samples of polybutadiene, Viton, Teflon, Silicone, PL 731 Adhesive, and SP 296 Boron-Epoxy composite was measured at temperatures from 25 to 150 C. Excellent correlations were obtained between chemiluminescence and temperature. These correlations serve to validate accelerated aging tests (at elevated temperatures) designed to predict service life at lower temperatures. In most cases, smooth or linear correlations were obtained between chemiluminescence and physical properties of purified polymer gums, including the tensile strength, viscosity, and loss tangent. The latter is a complex function of certain polymer properties. Data were obtained with far greater ease by the chemiluminescence technique than by the conventional methods of study. The chemiluminescence from the Teflon (Halon) samples was discovered to arise from trace amounts of impurities, which were undetectable by conventional, destructive analysis of the sample

Aerodynamic characteristics of a 1/6-scale model of the rotor systems research aircraft with the rotors removed

A wind-tunnel investigation was conducted to refine the aerodynamic characteristics of the rotor systems research aircraft. For the investigation, a 1/6-scale model without a main rotor or a tail rotor was used. The model provided the capability for testing different engine nacelle sizes, engine pylon fairings, and tail configurations. The engine thrust effects were modeled by small engine simulators (fans). Data were obtained primarily over an angle-of-attack range from -13 deg to 13 deg at several values of sideslip. Stability characteristics and control effectiveness were investigated. The model with the scaled engine nacelles and the combination T-tail and lower horizontal tail displayed longitudinal and lateral-directional stability. Results show that by reducing the horizontal or vertical-tail span the longitudinal stability is decreased. Reducing the engine nacelle size increases the static stability of the model. Effective dihedral is essentially zero at 0 deg angle of attack and 0 deg wing incidence

Full-scale wind tunnel-investigation of the Advanced Technology Light Twin-Engine airplane (ATLIT)

An investigation was conducted to evaluate the aerodynamic performance, stability, and control characteristics of the Advanced Technology Light Twin Engine airplane (ATLIT). Data were measured over an angle of attack range from -4 deg to 20 deg for various angles of sideslip between -5 deg and 15 deg at Reynolds numbers of 0.0000023 and 0.0000035 for various settings of power and flap deflection. Measurements were also made by means of special thrust torque balances to determine the installed propeller characteristics. Part of the investigation was devoted to drag cleanup of the basic airplane and to the evaluation of the effect of winglets on drag and stability

Prediction of service life of polymeric sealant compositions for fuel tanks in aerospace structures from measurements of viscoelastic properties Annual report

Prediction of service life of polymeric sealers for fuel tanks from viscoelastic measurement

Camping in WA National Parks: Visitors’ experiences and perceptions.

This report presents the findings of an interview--‐based study undertaken of campers’ experiences in two Western Australian national parks: Warren National Park and Karijini National Park. The overall aim of the study was to describe and analyse the desired and realised experiences of these campers and explore the meanings that campers attributed to these experiences. This report also describes the characteristics of these camping visitors, their perceptions of management and their opinions regarding camping in national parks compared with caravan parks

Perceptions of Electability: Candidate (and Voter) Ideology, Race, and Gender

Previous work has shown candidate electability is an important consideration to voters in deciding who to support. However, we do not know what candidate qualities voters consider more electable, especially in the absence of polling information. While scholarship has documented general election penalties for candidates with certain demographic and ideological characteristics, we do not know whether voters actually use these factors when judging electability. Using a conjoint experimental design, we examine how candidate characteristics influence perceptions of candidate electability. We find voters perceive women and minorities as less electable and ideologically extreme candidates as more electable. However, perceptions of electability vary with voter characteristics. Our results indicate that arguments about electability, for many individuals, are based on their own ideological preferences (and to a lesser extent, their identity) rather than systematically viewing candidates with attributes that provide general election advantages as more electable

Analysis of the linearity characteristics, tape recorders and compensation effects in the FM/FM telemetry system

Linearity characteristics, tape recorder effects, and tape speed compensation effects in FM/FM TELEMETRY syste