Report presenting the drag of a series of wing-body combinations by the free-fall method in order to provide information on the drag characteristics of promising transonic and supersonic airplane arrangements. Time histories, Mach number variations, and drag coefficients for several areas of the body are provided.

Memorandum presenting wind-tunnel tests of a semispan model of a hypothetical supersonic airplane to determine the static longitudinal stability and control characteristics of the airplane throughout the range of subsonic Mach numbers up to 0.95. The model had a long slender fuselage and a wing and horizontal tail of aspect ratio 4 and taper ratio 0.5. Results regarding the force and moment characteristics, wing wake and effective downwash at the horizontal tail, effects of compressibility, and longitudinal characterisitcs with the flaps deflected are provided.

"Investigations in the Langley 20-foot free-spinning tunnel of models of five jettisonable nose sections have shown that the airplane nose sections are inherently unstable but can be stabilized by the addition of suitable fins. An empirical criterion has been developed which indicates the fin area required for stabilizing an airplane jettisonable nose section" (p. 1).

Report presenting an investigation of the low-speed lateral characteristics of a 47.5 degree sweptback-wing-fuselage combination with several flap and spoiler aileron arrangements. Results regarding aileron control characteristics, spoiler-control characteristics, and a comparison of the two are provided.

Report presenting a study of the storage properties of fuming nitric acids, with and without additives, at 170 degrees F in closed containers of aluminum bodies and steel caps. The effects on the storage properties indicated that the potassium fluoride dihydrate is most effective in reducing the rate of pressure rise and reducing corrosion on aluminum and stainless steel surfaces.

Report presenting an investigation in the high-speed 7- by 10-foot tunnel to determine the effectiveness of a spoiler-slot-deflector combination in producing rolling moments in the transonic speed range at angles of attack as high as 24 degrees over a range of Mach numbers. The wing had an aspect ratio of 4, a taper ratio of 0.6, an unswept quarter-chord line, and NACA 65A006 airfoil sections.

Report presenting an investigation to determine the performance of a conical-nose supersonic diffuser at angle of attack. The inlet had a pivoting cone which could be oriented to any of several angles independent of the angle of attack of the diffuser. Results regarding total-pressure recovery and mass-flow characteristics, cowl lip position, cone position relative to angle of attack, shadowgraphs, and contour maps are provided.

Report presenting a flight investigation to study in detail the response of an airplane structure during buffeting. Measurements of acceleration on selected points were made during buffeting for two different conditions of lift coefficient and Mach number and the time histories of acceleration were studied using electrical frequency-analysis techniques. Results regarding the ground response measurements, response to buffeting excitation, verification of the measured results, and the pilot's observation of the buffeting are provided.

"Because previous work has indicated that jettisonable nose sections of airplanes may be inherently unstable, and thus may cause dangerous centripetal accelerations on a pilot after jettisoning during high-speed flight, an investigation has been conducted in the Langley 20-foot free-spinning tunnel to determine the behavior in descent of a model of the jettisonable nose section of the Douglas X-3 airplane. The effects of varying the center-of-gravity position, of attaching fins of various sizes, and of installing a stabilizing parachute were investigated. In the investigation the model descended with its front and trimmed 36 deg above the horizontal and rotated about a vertical wind axis while rolling about its longitudinal body axis" (p. 1).

The gust and draft velocities from records of NACA instruments installed in P-61c airplanes participating in thunderstorm flights at Clinton County Army Air Field, Ohio, from July 12, to July 18, 1947 are presented.

Report presenting an investigation in the 8- by 6-foot supersonic tunnel at a range of free-stream Mach numbers at zero angle of attack to determine the effects of internal corner fillets on the pressure recovery characteristics of twin-scoop conical-type inlets utilizing boundary layer removal and mounted on the RM-10 body. Without boundary layer removal, the use of fillets resulted in substantial improvements in pressure recoveries and near critical mass flows up to a certain Mach number.

"Results are given of pressure-distribution measurements made over two different horizontal tail surfaces and the right wing cellule, including the slipstream area, of an observation-type biplane. Measurements were also taken of air speed, control-surface positions, control-stick forces, angular velocities, and accelerations during various abrupt maneuvers. These maneuvers consisted of push-downs and pull-ups from level flight, dive pull-outs, and aileron rolls with various thrust conditions" (p. 319).

"Free-flight tests in the transonic and supersonic speed ranges utilizing rocket-propelled models have been made on two pairs of 1/9-scale Convair YF-102 airplane wings with elevons to investigate the possibility of flutter . These wings had modified 60 deg delta plan forms with the trailing edge swept forward 5 deg. The aspect ratio of two exposed wing panels was 2.19 and the wings had NACA 0004-65 (modified) airfoil sections. The model wings and elevons were dynamic-scale models at sea level of the full-scale wings at 20,000 feet" (p. 1).