Memorandum presenting a theoretical analysis of the supersonic flow about two-dimensional and three-dimensional axially symmetric models restricted by theoretical walls capable of removing the nose shock. Results regarding the supersonic-tunnel interference due to nonreflecting walls and supersonic-tunnel interference due to porous walls are provided.

Memorandum presenting a study of the performance of swirl-can combustor elements for an experimental short-length turbojet combustor utilizing hydrogen fuel at high-altitude operating conditions. Fuel was injected into each element through a tangential, sonic orifice that created a swirling fuel-air mixture within each element. Results regarding combustor blowout, combustion efficiency, outlet temperature distribution, and preliminary performance of multielement combustor are provided.

"Some aileron load characteristics for three thin wings varying in sweep have been presented for Mach numbers from 0.80 to 1.05. For the transonic Mach number range, shock effects exert a large influence on the loading, but the exact location of each shock for a specific wing design cannot be cataloged at the present time. It is shown, however, that the aileron loading, although greater in magnitude than at subsonic speeds, nevertheless varies in as uniform a fashion as at subsonic speeds" (p. 1).

Report presenting an investigation to determine the possibility of using simplified procedures for the estimation of control loads at supersonic speeds. The results indicated that relatively simple procedures are possible for the estimation of loadings on flap-type controls at supersonic speeds for cases when no flow separation occurs ahead of the hinge line.

Report presenting a wind-tunnel investigation at subsonic Mach numbers up to 0.9 to measure the root-mean-square variation of the normal forces on 27 NACA airfoil sections. The effects of thickness-chord ratio, camber, location of minimum pressure, and leading-edge radius were investigated.

Report presenting a consideration of the problem of shaping an adjoining fuselage for a given wing and supersonic Mach number so that the combination will have a low wave drag. Only fuselages that can be simulated by singularities distributed along the body axis are studied.

Report presenting a blade-vibration and rotating-stall survey on a modified version of a production turbojet engine with a 13-stage axial-flow compressor with a design pressure ratio of 7 and an air flow of 120 pounds per second. This testing was carried out due to the problems rotating stall can cause with both experimental and production axial-flow compressors. Results regarding the rotating-stall patterns, rotor-blade vibrations, radial and axial strength of rotating stall, and maximum rotating-stall speed are provided.

Memorandum presenting the Bell X-5 research airplane tested at 58.7 degrees sweepback during the program to determine the characteristics of a variable-sweep fighter airplane at transonic speeds. This paper includes the stability and control characteristics in the stable lift range up to Mach numbers near 1.0 at an altitude of 40,000 feet and to slightly lower Mach numbers at altitudes of 25,000 feet and 15,000 feet. Results regarding general comments, static stability and control characteristics, and longitudinal dynamic stability are provided.

Report presenting an exploratory investigation of three aluminum disoaps of C(sub 8) acids to determine the gelling properties and stabilizing ability in slurries of 50 percent magnesium power and JP-4 fuel. All of the soaps were found to gel the slurries satisfactorily and to exhibit adequate reproducibility of gel properties. Results regarding the soap behaviors, effects of temperature, viscosity, and formation of the gel structures are provided.

Memorandum presenting pulse techniques applied to strain gages for increasing the output level and extending the usable range. Bonded and unbonded strain gages which normally operate with exciting potentials between 3.5 and 14 volts operated satisfactorily with 200-volt pulses of 1-microsecond duration and a repetition rate of 350 per second. Results regarding maximum allowable voltages, effective pulse duration, sensitivity, minimum readable signal, effects of cable capacitance and inductance, sensitivity to external noise, and linearity are provided.

Memorandum presenting a turbojet engine with a two-stage turbine operated with pentaborane fuel continuously for 11.5 minutes at a simulated altitude of 55,000 feet at a flight Mach number of 0.8. The engine incorporated an NACA combustor designed specifically for use with pentaborane fuel. Results regarding oxide formation and deposition, engine operating point, effect of oxide deposits on component performance, effect of oxide deposition on overall performance, and some operational comments are provided.

Memorandum presenting results of a supersonic flutter investigation of three low-aspect-ratio control surfaces. Two controls were all-movable but the third had a fixed cutout. Results regarding the experiments and calculations are provided.

Memorandum presenting force-oscillation tests made in the 8-foot transonic pressure tunnel to investigate some effects of an overhang-type aerodynamic balance and of a flow spoiler on the dynamic hinge-moment characteristics of a full-span flap-type rudder on a 5-percent-thick, swept vertical fin of low aspect ratio. Test results how that the aerodynamic damping moment on the plain rudder becomes unstable near a Mach number of 0.975 and remains unstable to the maximum speed of the tests.

Report presenting performance of a two-dimensional external-compression inlet designed for various methods of inlet-engine matching up to Mach 3 at Mach 1.89 and Mach 0. Results regarding shock geometry, two-shock ramps, isentropic ramps, profiles, and cowl drag for the various Mach number tests are provided.

Memorandum presenting an investigation of the performance of inlet configurations with a forebody designed for isentropic external compression at a nominal Mach number of 5.6. At zero angle of attack, all the configurations yielded larger total-pressure recoveries than had previously been obtained with a single-conical-shock inlet. Results regarding the flow about the forebody, inlet performance, and performance comparisons are provided.

Memorandum presenting an investigation of hemispherical nose shapes of titanium, stainless steel coated with aluminum oxide, and uncoated stainless steel with lithium hydride and magnesium as internal coolants. Results regarding titanium models, stainless-steel models (uncoated), stainless-steel models coated with aluminum oxide, solution effects on the decomposition temperature of lithium hydride, effect of lithium hydride and magnesium on temperature measurements, and efficiency of models cooled with lithium hydride are provided.

Transonic flutter derivatives for unswept wing control surface configurations determined by pressure cell measurements. The control surfaces were mounted on a wing with an aspect ratio of 3, a taper ratio of 0.6, and a wing-thickness ratio of 0.06. Results regarding aerodynamic balance, vortex generators, splitter-plate configurations, and wedges are provided.

Memorandum describing an investigation using two airplanes, an F6F-3 and F-86A, each fitted with servo equipment for varying in flight the lateral and directional stability and handling characteristics, which have been flown by test pilots to simulate the predicted dynamic behavior of six prototype airplanes. The methods of simulation and the types and ranges of variables considered are presented and the results of the individual programs are discussed.

"A study has been made of a flare-cylinder configuration to investigate its feasibility as a reentry body of an intermediate range ballistic missile. Factors considered were heating, weight, stability, and impact velocity. A series of trajectories covering the possible range of weight-drag ratios were computed for simple truncated nose shapes of varying pointedness, and hence varying weight-drag ratios" (p. 1).

An investigation was conducted on a 35 deg swept-wing fighter airplane to determine the effects of several blunt-trailing-edge modifications to the wing and tail on the high-speed stability and control characteristics and tracking performance. The results indicated significant improvement in the pitch-up characteristics for the blunt-aileron configuration at Mach numbers around 0.90. As a result of increased effectiveness of the blunt-trailing-edge aileron, the roll-off, customarily experienced with the unmodified airplane in wings-level flight between Mach numbers of about 0.9 and 1.0 was eliminated, The results also indicated that the increased effectiveness of the blunt aileron more than offset the large associated aileron hinge moment, resulting in significant improvement in the rolling performance at Mach numbers between 0.85 and 1.0. It appeared from these results that the tracking performance with the blunt-aileron configuration in the pitch-up and buffeting flight region at high Mach numbers was considerably improved over that of the unmodified airplane; however, the tracking errors of 8 to 15 mils were definitely unsatisfactory. A drag increment of about O.OOl5 due to the blunt ailerons was noted at Mach numbers to about 0.85. The drag increment was 0 at Mach numbers above 0.90.

Report presenting an investigation at Mach numbers of 1.61 and 2.01 to determine the pressure distributions for a series of 20 controls on a 60 degree delta wing. Tests occurred at a range of angles of attack and control deflections. Results regarding basic pressure distributions, comparison of experimental and theoretical results, and experimental comparisons are provided.

Report presenting an investigation of the use of aerodynamic and mechanical devices for improving the response of guided missiles. An analysis indicates that the use of free-floating flaps and spring-mounted control surfaces should be able to increase maneuverability to the point that electronic automatic stabilization and gain-adjusting devices can be eliminated.

Report presenting an investigation conducted with trimethyl borate azeotrope and pentaborane fuels in a turbojet combustor. The primary purposes of the study were to determine the effect of boron oxide deposits on the turbine-nozzle area, combustor pressure loss, temperature distribution, and combustion efficiency. Three distinct boron deposit patterns were noted in the investigation.

"Investigations have been made in flight and in wind tunnels to determine which components of turbojet installations are most critical in icing conditions, and to evaluate several methods of icing protection. From these studies, the requirements necessary for adequate icing protection and the consequent penalties on engine performance can be estimated. Because investigations have indicated that the compressor-inlet screen constitutes the greatest icing hazard and is difficult to protect, complete removal or retraction of the screen upon encountering an icing condition is recommended" (p. 1).