National Advisory Committee for Aeronautics (NACA) - 9 Matching Results

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Altitude-wind-tunnel investigation of thrust augmentation of a turbojet engine II: performance with water injection at compressor inlet
Report presenting testing of a standard turbojet engine by water injection at the inlet of the axial-flow compressor in the altitude wind tunnel. Engine performance at 7600 rpm was obtained over a wide range of water-air-pressure ratios and ram-pressure ratios. Results regarding the engine-component performance are also provided.
Evaluation of Gust and Draft Velocities from Flights of P-61C Airplanes Within Thunderstorms August 14, 1946 to August 15, 1946 at Orlando, Florida
Tables I and II of the present paper summarize the gust and draft velocity data for thunderstorm-flights 21 and 22 of August 14, 1946 and August 15, 1946, respectively. These data were evaluated from records of NACA airspeed-altitude and acceleration recorders installed in P-61C airplanes and are of the type presented for previous flights. Table III summarizes the readings of a milliammeter which was used in conjunction with other equipment to indicate ambient-air temperature during thunderstorm surveys. These data were read from photo-observer records and include all cases in which variations of the instrument indications were noted for the present flights.
Factors affecting the design of quiet propellers
From Summary: "The problems associated with propeller noise and with the design of propellers that are less noisy than those conventionally used are presented. Three aspects of these problems are discussed: acoustical, aerodynamic, and structural. Some of the factors which must be considered in the design of a quiet propeller are outlined."
Force Tests of a 1/5-Scale Model of the McDonnell XP-85 Airplane with Conventional Tail Assembly in the Langley Free-Flight Tunnel
At the request of the Air Materiel Command, Army Air Forces an investigation of the low-speed, power-off stability and control characteristics of the McDonnell XP-85 airplane is being conducted in the Langley free-flight tunnel. The XP-85 airplane is a parasite fighter carried in a bomb bay of the B-36 airplane. As a part of the investigation a few force tests were made of a 1/5 scale model of the XP-85 with a conventional tail assembly installed in place of the original design five-unit tail assembly. The total area of the conventional assembly was approximately 80 percent of the area of the five-unit assembly. The results of this investigation showed that the conventional tail assembly gave about the same longitudinal stability characteristics as the original configuration and improved the directional and lateral stability.
High-Speed Wind-Tunnel Investigation of the Lateral Control Characteristics of Plain Ailerons on a Wing with Various Amounts of Sweep
A three-dimensional investigation of straight-sided-profile plain ailerons on a wing with 30 degrees and 45 degrees of sweepback and sweepforward was made in a high-speed wind tunnel for aileron deflections from -10 degrees to 10 degrees and at Mach numbers from 0.60 to 0.96. Wing configurations of 30 degrees generally reduced the severity of the large changes in rolling-moment and aileron hinge-moment coefficients experienced by the upswept wing configurations as the result of compression shock and extended to higher Mach numbers the speeds at which such changes occurred.
Investigation of Pressure Distribution over an Extended Leading-Edge Flap on a 42 Degrees Sweptback Wing
Pressure distribution over an extended leading-edge flap on a 42 degree swept-back wing was investigated. Results indicate that the flap normal-force coefficient increased almost linearly with the angle of attack to a maximum value of 3.25. The maximum section normal-force coefficient was located about 30 percent of the flap span outboard of the inboard end and had a value of 3.75. Peak negative pressures built up at the flap leading edge as the angle of attack was increased and caused the chordwise location of the flap center of pressure to be move forward.
Investigation of wing characteristics at a Mach number of 1.53 I : triangular wings of aspect ratio 2
No Description Available.
Preliminary Evaluation of the Low-Speed Stability and Control Characteristics of the McDonnell XP-85 Airplane from Tests of an Unballasted 1/5-Scale Model in the Langley Free-Flight Tunnel
At the request of the Air Material Command, Army Air Forces an investigation of the low-speed, power-off stability and control characteristics of the McDonnell XP-85 airplane is being conducted in the Langley free-flight tunnel. The XP-85 airplane is a jet propelled, parasite fighter with a 34 deg sweepback at the wing quarter chord. It was designed to be carried in a bomb bay of the B-36 air plane. The first portion of the investigation consists of a preliminary evaluation of the stability and control characteristics of the airplane from force and fight tests of an unballasted 1/5-scale model. The second portion of the investigation consists of test of a properly balasted 1/10-scale model which will include a study of the stability of the Xp-85 when attached to the trapeze for retraction into the B-36 bomb bay. The results of the preliminary test with the 1/5-scale model are presented herein. This portion fo the investigation included tests of the model with various center fin arrangements. Both the design nose flap and a stall control vane were investigated.
Results of preliminary flight investigation of aerodynamic characteristics of the NACA two-stage supersonic research model RM-1 stabilized in roll at transonic and supersonic velocities
Report presenting the design of a two-stage, solid-fuel, rocket-propelled, general research pilotless aircraft suitable for investigating stability and control at supersonic velocities. The flight test investigation is described and information is provided for zero-length launchers and operational flight-test techniques of two-stage rockets. Results regarding launching characteristics and lateral stabilization and control flight tests are provided.