Report presenting an investigation conducted to determine the overall performance of the J73 two-stage turbine with a standard rotor-blade configuration. The turbine operated with a maximum brake internal efficiency between 0.91 and 0.92 at an overall pressure ratio of about 3.4 and 120 percent equivalent design rotor speed. Results regarding the overall performance, variation of equivalent weight flow with overall pressure ratio, and effect of limiting blade loading are provided.

A preliminary investigation was conducted to determine the combustion characteristics of a fuel composed of 50 percent pentaborane and 50 percent JP-4 (MIL-F-5624A) by weight in a turbojet combustor. A combustor designed to fit the housing of a J33-A-23 turbojet engine was selected for convenience. The fuel was evaluated at two engine conditions simulating altitudes of 40,000 and 57,000 feet, an engine speed of 85 percent of rated rpm, and a flight Mach number of 0.6. The pentaborane blend was initially evaluated in combustors developed for pure pentaborane and diborane reported in NACA RM E53B18 and RM E52L15. The performance of the blend was unsatisfactory in these combustors. A new combustor was then developed which provided combustor efficiencies measured from 91 to 101 percent as compared with efficiencies of 92 to 94 percent previously obtained for pentaborane at comparable conditions. Additional refinements of design details are needed to obtain lower oxide deposits and a more uniform outlet temperature profile; however, the combustor is believed to incorporate some of the design principles required to obtain satisfactory over-all performance with the fuel blend investigated.

Report presenting an investigation to determine the feasibility of utilizing a reduced-chord rotor blading on the two-stage turbine of the J73 turbojet engine in order to reduce the weight. The turbine was operated as a component over a range of speeds and overall pressure ratios at turbine-inlet conditions corresponding to 35 inches of mercury absolute and 700 degrees R. Results regarding the overall performance, performance map, and peak efficiency are provided.

Report presenting an evaluation of the stage performance of the J73 turbine on the basis of previous performance investigations of the first stages alone and of the two-stage turbines with standard and with reduced-chord rotor blading for a range of rotational speeds and pressure ratios. The results demonstrated that both of the two-stage turbines and first-stage turbines had comparable performance.

Report presenting an investigation of an axial-flow compressor rotor with an inlet hub-tip radius ratio of basically zero. Results regarding the radial distribution of total-pressure ratio and efficiency, measured pressure ratio at design speed, weight flow, and low-speed cascade data are provided.

Report presenting an investigation of the static lateral stability characteristics of a swept-wing fighter-type airplane with three vertical-tail configurations and two wing configurations at an altitude of 40,000 feet over a range of Mach numbers. Data was obtained in several conditions, including constant-heading sideslips and wings-level turns, aileron rolls, and abrupt rudder pulses. Results regarding the sideslip characteristics, lateral control, and control effectiveness derivatives are provided.

From Summary: "The manner in which imperfect space stabilization of the tracking radar influences the flight path stability of an automatic interceptor during the attack phase is illustrated by means of flight and analog-computer time histories. It is shown analytically that these effects may be interpreted in terms of a destabilizing airplane rate feedback which can be canceled by an additional compensatory feedback in the radar tracking loop."

"The multistage turbine from the J73 turbojet engine has previously been investigated with standard and with reduced-chord rotor blading in order to determine the individual performance characteristics of each configuration over a range of over-all pressure ratio and speed. Because both turbine configurations exhibited peak efficiencies of over 90 percent, and because both units had relatively wide efficient operating ranges, it was considered of interest to determine the performance of the first stage of the turbine as a separate component. Accordingly, the standard-bladed multistage turbine was modified by removing the second-stage rotor disk and stator and altering the flow passage so that the first stage of the unit could be operated independently" (p. 1).