From Summary: "A flight investigation has been made of the practical problems associated with the use of porous-leading-edge suction. The wing leading edge of the test airplane was porous over approximately 83 percent of the span and the first 8 percent of the chord on the upper surface. Various other extents of suction area within these limits were also tested."

Report presenting an investigation of a 1/19-scale model of an unswept-wing trainer airplane in the 20-foot free-spinning tunnel to determine the rocket spin-recovery characteristics of the model for comparison with available full-scale-airplane results. A rocket was attached to each wing tip to fire in a direction to apply an antispin yawing moment about the Z body axis. Results regarding the full-scale spin recoveries by rockets, model spin recoveries by rudder reversal, model spin recoveries by rockets, and mass changes associated with installation of emergency device are provided.

Note presenting an investigation of some of the possible mathematical troubles that may occur in the iterative procedure so much in use in present-day aerodynamics. The analysis indicates the general undesirability of determining the velocity potential or the stream function in the form of a series whose coefficients are analytically developed in a power series of some parameter.

Report presenting a soap-bubble, constant-pressure method to measure laminar burning velocities of some hydrocarbon-nitrogen-oxygen mixtures. Results regarding the evaluation of the soap-bubble method of measurement and burning velocities of hydrocarbon-oxygen-nitrogen mixture are provided.

Note presenting an analysis of the propulsive thrust and specific impulse attainable by cooling aircraft surfaces with liquefied or solidified gases with vaporization temperatures lower than the equilibrium surface temperature. Use of coolant vaporization as the sole means of propulsion yields low specific impulses at low speeds.

Report presenting a study of the flow distribution throughout the passage of a rotating impeller, and the results are presented in the form of relative velocity and relative pressure loss contours. The loss and velocity distributions indicate that secondary flows in the boundary layer tend to shift the low-energy air toward the blade suction within the passage. Results regarding the overall performance, performance within the passage, secondary flow and clearance effects, and a comparison with the hot-wire anemometer surveys are provided.

Note presenting the effect of inclination of the airstream on the static pressure measured by two essentially similar service pitot-static tubes and by one of those tubes with three modified orifice arrangements as determined in flight. Results regarding initial calibrations at Mach numbers from 0.20 to 0.24 and the final orifice configuration are provided.

"The analogy between a ball rolling over a contoured surface and a pitching and yawing aircraft is developed. Test results from a model representing a missile with linear moment characteristics are presented to verify the analogy. Several examples of the behavior of nonlinear systems are also given" (p. 1).

Report presenting some information relative to the prediction of shock-induced boundary-layer separation. Experimental results showing the effects of Reynolds number and Mach number on the separation of both laminar and turbulent boundary layers are given and compared with results obtained by available methods for predicting separation.

Report presenting an investigation of laminar, transitional, and turbulent boundary layers in a subsonic wind tunnel at two Mach numbers at various Reynolds numbers and stations along a flat plate. Comparisons are made of the density profiles obtained with a total-pressure probe of small frontal opening and by means of an X-ray absorption method and, in a few cases, by using interferometer data.