Report presenting tests to determine the effects of sweepback angle and aspect ratio on the drag of an NACA 65-009 airfoil at supersonic speeds. The results indicated that for the range of Mach numbers investigated, increasing the sweepback angle and decreasing the aspect ratio reduced the value of the wing drag coefficient.

The heat of combustion of the product formed by the reaction acetylene and diborane was found to be 20,100 +/- 100 Btu per pound for the reaction of liquid fuel to gaseous carbon dioxide, gaseous water, and solid boric oxide. The measurements were made in a Parr oxygen-bomb calorimeter, and chemical analyses both of the sample and of the combustion products indicated combustion in the bomb calorimeter to have been 97 percent complete. The estimated net heat of combustion for complete combustion would therefore be 20,700 +/- 100 Btu per pound.

Report presenting the use of Von Karman's two-dimensional transonic similarity law as applied to drag data of three different thickness wings with NACA 65-series sections and aspect ratios of 7.6 over a range of Mach numbers. The correlation was found to be satisfactory, with results better in the subsonic range than in the supersonic range.

Report discussing the aerodynamic characteristics of a twin-fuselage pursuit airplane model, especially at high speeds. Information about the force data and critical Mach numbers for parts of the model is provided. Suggestions for increasing the Mach number of divergence by making modifications to the wing-fuselage fillets and external shape of the radiator are also included.

Memorandum presenting flight and wind-tunnel measurements made of the low-speed stalling characteristics on a swept-wing jet aircraft. Included in the study are the effects on the stalling characteristics of a number of wing modifications. Results regarding the roll-off characteristics and maximum lift and stalling characteristics are provided.

"This report contains the flight-test results of the lateral and directional-stability and control phase (including tests with wing-tip tanks) of a general flying-qualities investigation of the Lockheed P-80A airplane (Army No. 44-85099). These tests were conducted at indicated airspeeds up to 494 miles per hour (0.691 Mach number) at low altitude and up to 378 miles per hour (0.816 Mach number) at high altitude. These tests showed that the flying qualities of the airplane were for the most part in accordance with the requirements of the Army Air Forces Stability and Control Specifications" (p. 1).

From Summary: "Flight tests were conducted on a straight-wing fighter-type jet airplane to investigate the lateral-control characteristics associated with a wing-dropping tendency encountered at high subsonic Mach numbers. The chief factors found to account directly for the wing-dropping tendency were a progressive reduction in aileron-control effectiveness with increasing Mach number, and an increase in effective dihedral above a Mach number of 0.8 which made the lateral trim particularly sensitive to small changes in sideslip angle."

An investigation is being conducted to determine the altitude performance characteristics of the British Nene II engine and its components. The present paper presents the preliminary results obtained using a standard jet nozzle. The test results presented are for conditions simulating altitudes from sea level to 60,000 feet and ram pressure ratios from 1.0 to 2.3. These ram pressure ratios correspond to flight Mach numbers between zero and 1.16 assuming a 100 percent ram recovery.

Report presenting the air-flow behavior over the wing of an XP-51 airplane including photographs of tufts attached to the wing surface and chordwise pressure distributions. A comparison of tuft studies from flight results are compared with results from wind-tunnel testing. Three types of flow were observed: steady flow, unsteady flow, and break-away flow are provided.

A spin-recovery investigation has been conducted in the Langley 20-foot free-spinning tunnel on a 20-scale model modified to represent the McDonnell XF2H-1 airplane. The project included tests both with tip tanks installed and with the tanks removed. The results indicated that the recovery characteristics of the airplane would be satisfactory for all loadings by normal recovery technique (full reversal of the rudder, followed 1/2 turn later by movement of the elevator down). The rudder pedal and the elevator stick forces likely to be encountered in a spin should be within the capabilities of the pilot.

"A supplementary investigation has been conducted in the Langley 20-foot free-spinning tunnel of a 1/30 -scale model of the Grumman XF10F-1 airplane to determine what effect full-span slats would have on the spin-recovery characteristics of the swept-wing version of the XF10F-1 airplane, which had previously been indicated as possessing undesirable spin-recovery characteristics without slats. The effects of extended nose-wheel doors and of fairing the air-duct inlets were also determined" (p. 1).

Report discussing about 400 references pertaining to the hydrodynamic design of seaplanes have been compiled, and the information is presented in the form of abstracts classified under six main headings.

Report presenting a flight investigation on a rectangular ram jet over a range of fuel air ratios, combustion chamber inlet velocities, and pressure altitudes. A comparative study to determine the effects of altitude, combustion-chamber-inlet velocity, and fuel-air ratio on starting characteristics, minimum blow-out limits, combustion efficiency, gas total-temperature ratio, and net-thrust coefficient for three flame holders was also conducted.

Report presenting a wind-tunnel investigation to determine the aerodynamic characteristics of a wing-nacelle combination at high subsonic speeds. Lift, drag, pitching-moment, and ram-recovery data re presented for a range of Mach and Reynolds numbers.

From Introduction: "The purpose of this paper is to present an analytical method for the design of two-dimensional related selection of a blade for particular rotor conditions may be made quickly and easily and its performance deduced from tests of representative sections in cascade."

Report presenting some accompanying tables and bibliography for experimental aerodynamic studies in the field of wing controls during the period between January 1946 and February 1955. The tables are grouped according to the following major classifications: trailing-edge flap controls, leading-edge flap controls, and spoiler controls.

Report presenting flight measurements of the buffeting characteristics of the Bell X-5 airplane at 58.7 degrees of sweepback at a range of Mach numbers and altitudes. Information about tail buffeting and wing buffeting at several angles of attack is provided. The pilot considered the buffeting to be unobjectionable throughout the entire test region.

Memorandum presenting a description of the equipment used in the Ames supersonic free-flight wind tunnel to obtain the data necessary to measure the aerodynamic characteristics of free-flying models. The model is fired from a gun into the supersonic air stream of a blowdown-type wind tunnel. The action resulting from aerodynamic forces is computed from a time-distance-attitude record of the model flight through the test section.

Report presenting testing of free-falling recoverable-model tests at transonic speeds on a model with an aspect-ratio-4 triangular wing and a 45 degree sweptback tail in the extended wing-chord plane. Results regarding the lift, drag, stability, tail effectiveness, and buffet boundary are provided.

"From tests made in the altitude chamber of the Bureau of Standards, it was found that the effect of humidity on engine power is the same at altitudes up to 25,000 feet as at sea level. Earlier tests on automotive engines, made under sea-level conditions, showed that water vapor acts as an inert diluent, reducing engine power in proportion to the amount of vapor present. By combining the effects of atmospheric pressure, temperature, and humidity, it is shown that the indicated power obtainable from an engine is proportional to its mass rate of consumption of oxygen" (p. 523).

Report presenting an investigation to evaluate two methods of decreasing losses of unevaporated fuel from the combustion zone of turbojet-engine combustors. One method had fuel dams on the inner surface of the combustor liner and one had a ceramic coating on the combustor-liner walls. Results regarding the effect of the fuel dams, effect of ceramic coatings, effect of combination of fuel dams and ceramic coatings, and effect of ceramic coating on carbon deposition are provided.

Report presenting an investigation of a 45 degree sweptback-wing model with interchangeable round and sharp leading edges to determine the effect of leading-edge separation on the loads experienced by the models in gusts. Leading-edge separation was found to increase the gust load, which appeared to vary based on the gust-gradient distance and velocity.

"This paper presents the results of an investigation of sting-support interference on afterbody drag at transonic speeds. Stings with varying diameter, cone angle, and cylindrical length were tested at the rear of a model with various afterbody shapes. The data were obtained at an angle of attack of 0 deg. and at Mach numbers from 0.80 to 1.10. It was found that, in general, the addition of a sting caused a drag reduction" (p. 1).

Report presenting an investigation of the flow field behind a hydrofoil with an 8-inch chord and an aspect ratio of 10; the foil was operating at about 0.75 chord below the free-water surface. The downwash and water surface profiles were measured behind the hydrofoil for a variety of positions of interest. Results regarding surface contours, a comparison of surface profiles with theoretical two-dimensional waves, and downwash are presented.