Memorandum presenting characteristics of a hydraulic control as determined by analyzing transient data obtained with a turbojet engine operating in the altitude wind tunnel. The excellent overall performance of the speed control is attributed to the elimination of large lags in the control system, thereby permitting the use of relatively high loop gains while still maintaining satisfactory damping in transients. Some information regarding the frequency-response analysis of speed control, simulation of speed control, and acceleration control are provided.

Report presenting comparisons of low-lift drag measurements on eight airplane configurations at a range of Mach numbers by various techniques. Data was obtained from wind tunnel testing, rocket propelled model tests, and airplane flight tests. The agreement of data is generally good and no consistent Reynolds number effects are observed.

Combined compressor coolant injection and afterburning for turbojet engine thrust augmentation.

Report presenting a discussion of some of the requirements and of the application of the augmented performance of compressor coolant injection and afterburning in a turbojet engine in a high-speed, high-altitude flight. Results regarding the experimental performance of a combined system and the application of augmented performance to high-speed flight are provided.

Report presenting an experimental vaporizing annular combustor that evolved from a high-performance annular combustor developed for vapor-fuel injection. The combustor consisted of a one-quarter sector of a single-annulus combustor designed to fit in a housing with an outside diameter of 25.5 inches, an inside diameter of 10.6 inches, and a combustor length of approximate 23 inches. Results regarding the performance of the Model 29I combustor, performance of Model 30, and performance of the best combustor configuration are provided.

Report presenting comparisons of low-lift drag measurements on eight airplane configurations at a range of Mach numbers using various techniques. Data was obtained from wind-tunnel testing, rocket-propelled model testing, and airplane flight testing. The majority of the data showed agreement and discrepancies were likely due to issues regarding surface condition, individual test setup and accuracy, and detail geometric differences between the airplanes and respective models.

Report presenting an investigation of the performance characteristics of a mixed-flow impeller (Model MFI-1B) in combination with a vaned diffuser. The results indicated that the peak pressure ratio and maximum efficiency were not being obtained at overdesign speeds because of premature surge. Increasing inlet angle at the leading edge of the vanes improved the pressure ratio and efficiency at overdesign speeds with little to no effect on underdesign speeds.

An investigation was conducted in the Langley high-speed 7- by 10-foot tunnel to determine effects of modifications to a bomb model (particularly with regard to drag) when mounted on a wing-fuselage model and tested at Mach numbers from 0.70 to 1.10. In addition, the static longitudinal stability characteristics of several configurations of a larger scale model of the bomb alone were obtained over a Mach number range from 0.50 to 0.95.

Report presenting an experimental investigation in a 16-inch ram-jet engine to examine the degree to which inlet flow pulsations influence the combustion efficiency and lean blow-out limit of a ram-jet combustor.

From Summary: "The effects of deflecting full-span, constant-chord, leading-edge flaps, having either round or sharp leading edges, upon the lift, drag, and pitching moment characteristics of a model of an interceptor-type aircraft have been determined experimentally at subsonic and supersonic speeds. Results indicate that the variations of lift with angle of attack and of pitching moment with lift were unaffected by either the shape of the flap leading edge or flap deflection. Deflection of the flaps having either a round or sharp leading edge increased the drag at zero lift at both subsonic and supersonic speeds. In spite of the increase in the drag at zero lift, however, deflection of the flaps increased the maximum lift-drag ratio at subsonic speeds and had no deleterious effect at supersonic speeds."