"An experimental investigation was made of a preloaded spring-tab flutter model to determine the effects on flutter speed of aspect ratio, tab frequency, and preloaded spring constant. The rudder was mass-balanced, and the flutter mode studied was essentially one of three degrees of freedom (fin bending coupled with rudder and tab oscillations). Inasmuch as the spring was preloaded, the tab-spring system was a nonlinear one" (p. 1).

"Low-speed wind-tunnel tests of a l/8 scale model of the Republic XP-91 airplane were made to determine its low-speed characteristics and the relative merits of a vee and a conventional tail on the model. The results of the tests showed that for the same amount of longitudinal and directional stability the conventional tail gave less roll due to sideslip than did the vee tail. The directional stability of the model was considered inadequate for both the vee and conventional tails; however, increasing the area and aspect ratio of the conventional vertical tail provided adequate directional stability" (p. 1).

Report presenting a combustion-efficiency investigation of 10 special straight-run distillate fuels in an individual tubular-type combustor unit of a 14-unit assembly at two simulated engine operating conditions. These distillates were obtained from various crude oils and consisted of hydrocarbon mixtures with distillations temperature varying from 93 to 690 degrees Fahrenheit. Comparison of temperature measurements obtained from two locations in the exhaust duct showed that under certain operating conditions the flame extended beyond the turbine position.

The performance at inlet pressure of 21 inches mercury absolute and inlet temperature of 538 R for the 10-stage axial-flow X24C-2 compressor from the X24C-2 turbojet engine was investigated. the peak adiabatic temperature-rise efficiency for a given speed generally occurred at values of pressure coefficient fairly close to 0.35.For this compressor, the efficiency data at various speeds could be correlated on two converging curves by the use of a polytropic loss factor derived.

Memorandum presenting an investigation of the change in spanwise load distribution at high Mach numbers, which is of considerable interest because lateral movement of the center of lift affects the trim, stability, and structural factors of safety of an airplane. The data is not sufficient to permit isolation of the effects of changes in wing configuration, but in a majority of cases, the tests reveal a tendency for the center of lift to shift outboard with increasing Mach number.

"A compilation of free-spinning-airplane model data on the spin and recovery characteristics of 111 airplanes is presented. These data were previously published in separate memorandum reports and were obtained from free-spinning tests in the Langley 15-foot and the Langley 20-foot free-spinning tunnels. The model test data presented include the steady-spin and recovery characteristics of each model for various combinations of aileron and elevator deflections and for various loadings and dimensional configurations" (p. 1).

"The factors that affect the rate of change of rolling moment with yaw of a typical fighter-type airplane were investigated in the Langley full-scale tunnel on a typical fighter-type airplane. Eight representative flight conditions were investigated in detail. The separate effects of propeller operation, of the wing-fuselage combination, and of the vertical tail to the effective dihedral of the airplane in each condition were determined. The results of the tests showed that for the airplane with the propeller removed, the wing-fuselage combination had positive dihedral effect which increased considerably with increasing angle of attack for all conditions" (p. 1).

"Preliminary tests have been made of a small burner to meet the requirements for application to supersonic ram jets. The principal requirements were taken as: (1) efficient combustion in a high-velocity air stream, (2) utilization for combustion of only a small fraction of the air passing through the unit, (3) low resistance to air flow, (4) simple construction, and (5) light weight. Tests of a small burner were carried to stream velocities of nearly 150 feet per second and fuel rates such that one-eighth to one-fourth of the total air was involved in combustion" (p. 1).