Report presenting a method by which incremental pitching moments can be estimated for swept and triangular wings with arbitrary types of trailing-edge high-lift flaps. Span-loading theory is combined with two-dimensional airfoil data adjusted for the effects of sweep. Application of the method is demonstrated for 58 cases covering various types of flaps on wings with a wide range of sweep, aspect ratio, and taper ratio.

Memorandum presenting the results of some investigations of separation on heat transfer and a method of reducing separation and shows the heat transfer in regions of separation and reattachment for a few specific shapes. The results show that heat transfer in a separated region is strongly affected by the extent of separation, the location of the reattachment point, and the location of transition along the separated boundary.

Free oscillation test to determine hinge moment of trailing-edge, flap control surface with various hinge-line positions at transonic speed. Results show that oscillating amplitude has a large effect on the control aerodynamic damping derivative and that the damping is unstable in the test Mach number range above about 0.90 for the hinge positions tested.

"An investigation has been made at large scale of the characteristics of highly swept wings. Data were obtained at several angles of sideslip on wings having angles of sweep of plus or minus 45 degrees, plus or minus 30 degrees, and 0 degrees. The airfoil sections of the wings varied from approximately NACA 0015 at the root to NACA 23009 at the tip. Each wing was investigated with flaps under flection, partial-span split flaps deflected 60 degrees, full-span split flaps defected 60 degrees and split-flap-type ailerons deflected plus or minus 15 degrees" (p. 1).

Report presenting an investigation of the distribution of pressure at zero lift over the surface of a swept airfoil of biconvex section. The measured pressures are compare with theoretical values calculated from thin-airfoil theory. Results regarding pressure distributions, drag, and boundary-layer studies are provided.

Report presenting an investigation of a family of turbine-rotor-blade designs based on one-dimensional-flow theory and incorporating systematic changes in design variables. They were designed for 40-percent reaction and a total-to-static pressure ratio of 4.00 based on the assumption of constant static pressure along the radius and one-dimensional-flow theory for the design of the rotor-blade passages.

From Summary: "Such devices as leading- and trailing-edge flaps which are now in use on operational aircraft permit the attainment of maximum airplane lift coefficients, power-off, of the order of 2.8 (reference 1). Airfoil-section maximum lift coefficients as high as 5.5 have been obtained in wind-tunnel tests (see, for example, reference 2), and in a limited flight investigation airplane lift coefficients of 4.2 were obtained (reference 3)."

Report presenting an investigation of systematic series of sharp- and blunt-trailing-edge wings to determine the effects of thickening the trailing edges on the lift, drag, and pitching moment characteristics at several Mach numbers. Results indicate that no appreciable zero-lift drag reduction can be obtained by thickening the trailing edges from 1.41 to 1.96, but trailing edges can be thickened appreciably with no increases in zero-lift drag.

Report presenting a wing-flow investigation to determine the lift, pitching-moment, and hinge-moment characteristics of an unswept and untapered NACA 65-009 airfoil model with an aspect ratio of 3.01 and a 1/4-chord full-span plain flap. Effects of sealing a portion of the length of the flap gap were investigated as well as adding roughness to a portion of the airfoil chord. Information about the maximum unstalled lift coefficient, compressibility phenomenon, and hinge-moment coefficient is also provided.

"Preliminary measurements have been made of velocity and temperature fluctuations in the flow behind a heated grid in a uniform airstream. Temperature correlation shows a reasonable degree of isotropy, and the temperature fluctuations die out at large distances more slowly than the turbulence, as has been predicted theoretically under some strongly simplifying postulates" (p. 1).

Report presenting an experimental investigation in the 7- by 10-foot tunnel in a range of Mach numbers to determine the drag and opening characteristics of a model of a Kaman Aircraft Corporation Rotochute. The Rotochute is a two-bladed flapping rotor with governor-controlled blades designed for lowering cargo containers from high-speed aircraft tested at various Mach numbers simulating constant rates of descent.

Report presenting an investigation in the 8- by 6-foot supersonic tunnel to determine the effects of a cold exhaust jet on the pressure loadings of an all-movable, 45 degree sweptback horizontal stabilizer located in a region influenced by the jet. Results indicated that at jet pressure ratios of 1 to 9, the exhaust jet did not appreciably affect the pressure loadings of the stabilizer.

Report presenting the performance of slurries of 50 percent boron in MIL-F-5624A grade JP-4 fuel evaluated in a 5-inch ramjet burner. Boron slurries were found to give higher heat outputs than JP-4 fuel only at fuel-air ratios above stoichiometric for JP-4 fuel. Testing found that it was also possible to determine the flow properties of particular batches of slurry before burning by flowing them through a bench system which would simulate the actual fuel system that would use the slurry.

Report presenting free-oscillation tests to determine the dynamic hinge-moment characteristics of a trailing-edge, flap-type control surface with various hinge-like positions. Oscillating amplitude was found to have a large effect on the control aerodynamic damping derivative and the damping was found to be unstable in the test Mach number range above 0.90 for the hinge positions tested. Results regarding damping moments and flutter characteristics, spring moments, and effect of hinge-line position and comparison with theory are provided.

"Methods and techniques developed for the study of buffeting by use of wind-tunnel models are described. Requirements on model damping and frequency characteristics, the model support system, and the effects of wind-tunnel turbulence on buffet tests are outlined. The results are shown of a recent comparison of buffet loads measured on a research airplane with thin unswept wings and on two different models of the airplane in two different wind tunnels" (p. 1).

Wind-tunnel investigations were made in pitch and yaw with and without split flaps. Presence of the fuselage had negligible effect on values of maximum lift coefficient and slope of lift curve, but caused a destabilizing shift in the rate of change of pitching moment with lift. Effects of fuselage position on drag characteristics were small for wings without flaps, but were appreciable when split flaps were on.

"An investigation of the spin and recovery characteristics of a 1/24-scale model of the Grumman XF9F-2 airplane with wing-tip tanks installed has been conducted-in the Langley 20-foot free-spinning tunnel. The effects of control settings and movements on the erect spin and recovery characteristics of the model for a range of possible loadings of the tip tanks were determined. Spin and recovery characteristics without tanks were determined in a previous investigation" (p. 1).

"Wind-tunnel tests of a full-scale model of the Republic XP-91 airplane were conducted to determine the longitudinal and lateral characteristics of the wing alone and the wing-fuselage combination, the characteristics of the aileron, and the damping in roll of the wing alone. Various high-lift devices were investigated including trailing-edge split flaps and partial- and full-span leading-edge slats and Krueger-type nose flaps. Results of this investigation showed that a very significant gain in maximum lift could be achieved through use of the proper leading-edge device" (p. 1).

The object of the investigation presented in this report was to determine the effects of increasing the air charge and scavenging the clearance volume of a 4-stroke-cycle compression-ignition engine having a vertical-disk form combustion chamber. Boosting the inlet-air pressure with normal valve timing increased the indicated engine power in proportion to the additional air inducted and resulted in smoother engine operation with less combustion shock. Scavenging the clearance volume by using a valve overlap of 145 degrees and an inlet-air boost pressure of approximately 2 1/2 inches of mercury produced a net increase in performance for clear exhaust operation of 33 percent over that obtained with normal valve timing and the same boost pressure. The improved combustion characteristics result in lower specific fuel consumption, and a clearer exhaust.

This report presents the results of wind tunnel tests on various auxiliary airfoils having three different airfoil sections and several different chord lengths in combination with a Clark Y model wing in a sufficient number of relative positions to determine the optimum with regard to certain criterions of aerodynamic performance. The airfoil sections included a symmetrical profile, one of medium camber, and a highly cambered one. The chord sizes of the auxiliary airfoils ranged from 7.5 to 25 percent of the chord of the main wing, and the span was equal to that of the main wing.

"This report is the second of a series presenting the results of strength tests of thin-walled duralumin cylinders and truncated cones of circular and elliptic section. It contains the results obtained from compression tests on 45 thin-walled duralumin cylinders of circular section with ends clamped to rigid bulkheads. In addition to the tests on duralumin cylinders, there are included the results of numerous tests on rubber, celluloid, steel, and brass cylinders obtained from various sources" (p. 585).