Memorandum presenting an investigation in natural icing conditions to determine the effect of ice formations on the performance of an axial-flow turbojet engine. A description of the change over time in tail-pipe temperature, engine jet thrust, fuel flow, ice collection, and acceleration qualities are provided.

Combustion chamber liners for gas turbines and experimental set-ups were tested for failure. A ceramic-lined test chamber was operated at fuel/air ratios up to 0.050. Thermal-shock evaluation indicated that a ceramic lining, which expands after firing, would crack but would not fall apart during operation. Refractoriness of the lining and the resistance to mechanical shock were adequate. In general, shell temperature reductions of approximately 400 deg F were effected by the use of this lining at fuel/air ratios of 0.016 and 0.050. The mechanism of failure of the ceramic lining was induced by sudden heating and cooling during operation.

Investigation at transonic speeds in the high-speed 7- by 10-foot tunnel to determine the rolling-effectiveness characteristics of a spoiler on a double-wedge-type semispan wing with a sweepback angle of 42 degrees. Results regarding the variation of rolling-moment coefficient, spoiler effectiveness, and rolling effectiveness are provided.

Report discussing an investigation of the DM-1 glider, which has an approximately triangular plan form, with auxiliary studies of a model of triangular wings. The pitching-moment coefficient, drag coefficient, and angle of attack with the lift coefficient are provided. Results indicated that the angles of descent without power are likely to be prohibitive and airplanes with the tested type of wings will not be able to land safely without power.

Report discussing testing of a model of the pilotless aircraft RM-1 to measure aileron hinge moments in flight in order to determine the reason for loss of roll stabilization at supercritical speeds in flight. The aileron was found to become quickly underbalanced over the full deflection range at supercritical speeds. Information about the general flight behavior, aileron hinge moments, and roll stabilization of the model is provided.

Report presenting an investigation of two symmetrical circular-arc airfoils of 6 and 10 percent thickness equipped with leading-edge and trailing-edge high-lift devices. A trialing-edge flap, drooped-nose flap, and leading-edge extensible flap were all tested. Results regarding the plain airfoils, airfoils with high-lift devices, combined deflection of high-lift devices, and low-drag-control flaps are provided.

Report presenting an investigation of two 10-foot-diameter three-blade propellers to determine the effect of swept-back blade tips on propeller aerodynamic characteristics. Results regarding the effect of swept-back tips on maximum efficiency and constant-power propeller operation are provided.

Memorandum presenting wind-tunnel tests that have been made to determine the aerodynamic characteristics of a model tail plane with modified NACA 65-010 sections and a tapered plan form. Results were obtained with the model tail plane unswept and swept back. The data show the lift, drag, pitching-moment, and hinge-moment coefficient variation with angle of attack and flap deflection at various Mach numbers.

Memorandum presenting an investigation conducted to provide data that may be used to correlate the engine service performance of cast Vitallium turbine buckets with metallurgical properties. Data were obtained from four turbine wheels of Timken alloy with cast Vitallium buckets. Examination of 12 broken buckets indicated that 8 of the failures were probably caused by fatigue and 4 by impact with pieces of other broken buckets.

Report presenting information about some of the fundamental concepts and lines of development that may be undertaken regarding helicopter stability. Some of the principles discussed include method of control, control lag, stability characteristics, control forces, and center of gravity. Some of the means for improvement discussed include use of a horizontal stabilizer, use of trim devices, use of power-operated controls, automatic controls, and choice and grouping of indicating instruments.

Report presenting comparative tests of the rolling power of plain constant-chord, full-delta, and half-delta ailerons on delta wings with varying degrees of sweepback were tested on rocket-propelled test vehicles. Results regarding the effect of leading-edge sweepback, a comparison of rolling effectiveness, and comparison with theory are provided.

Report presenting the results of testing on a model of the D-558-1 in order to determine its pitching-moment, lift, and drag characteristics with no nose-inlet flow, and with the tail removed and at a constant setting. Only a limited analysis is provided.

Report presenting the hydrodynamic characteristics of a swept planing-tail hull as determined by water tank testing. The hull shape was based on results from previous testing indicating that symmetrical airfoil sections and slender boom-like afterbodies lower the drag. Results regarding spray characteristics, take-off stability and trims, landing stability, resistance, and directional stability are presented.

Report presenting an investigation in the high-speed 7- by 10-foot tunnel to determine the high-subsonic aerodynamic characteristics of three different types of flying-boat hull: a planing-tail hull, a blended hull, and an airfoil-forebody swept hull.

From Introduction: "Analyses that provide a basis for comparing the centrifugal-stress distributions inherent in jet-engine turbine blades of several designs currently in use were therefore made and are presented."

Report presenting the results of flight tests showing lateral oscillation in the Bell X-1 and calculations created to determine the effects of changes in several mass and aerodynamic parameters on the lateral oscillations. Calculations indicate that lateral stability should be improved by a more positive inclination of the principal axis of inertia or a reduction of the value of yawing moment of inertia.

Report presenting the pressure-recovery characteristics of a model with two scoops situated on the aft position of a long forebody and connected through diffusors to a common settling chamber at a range of Mach numbers. The effects of interaction between the flow in the two air-induction systems and of varying the mass flow through the boundary-layer scoops were studied. Results at several different angles of attack are provided.

Memorandum presenting high-speed wind-tunnel testing to investigate the aerodynamic characteristics at subsonic speeds of two symmetrical double-wedge airfoil sections of 4- and 6-percent-chord thickness suitable for application to supersonic aircraft. Section coefficients of lift, drag, and quarter-chord pitching moment are presented for a moderate range of angles of attack at Mach numbers up to approximately 0.93. The double-wedge airfoil exhibits no characteristics other than those common to the usual subsonic profile which would contribute to unsteady or uncontrollable flight at subsonic speeds of aircraft employing such a section for lifting surfaces.

Report presenting an investigation at subsonic and transonic speeds in the high-speed 7- by 10-foot tunnel to determine the aerodynamic characteristics of a 42.7 degree sweptback wing with a 20-percent-chord and 50-percent-span outboard aileron. The investigation was performed in transonic flow over a bump on the tunnel floor and in subsonic flow on one of the tunnel side walls.

Report presenting the results of a wind-tunnel investigation of aileron flutter up to 0.822 Mach number. The testing indicated the absence of flutter of significant amplitude when a considerable amount of wing-tip relief existed and the presence of flutter when the relief was minimized. Results regarding the testing without the end plate, with end plate, and comparison with theory are provided.

Report presenting an analysis of the effects of compressibility on the pressure coefficients of several bodies of revolution by comparing experimentally determined pressure coefficients with corresponding pressure coefficients calculated by the use of linearized equations of compressible flow. The results indicated that the theoretical methods predict the subsonic pressure-coefficient changes over the central portion of the body but do not predict the pressure-coefficient changes near the nose.

Report presenting a supersonic compressor design with supersonic velocity at the entrance of the stator on the assumption of two-dimensional flow. The rotor and stator losses assumed in the analysis are based on the results of preliminary supersonic cascade tests. The starting conditions and stability of the flow in rotor and stator are discussed, and the desirability of the variable-geometry stators and adjustable guide vanes is indicated.

"Four 90 degree two-dimensional turning passages designed by the method of characteristics were tested at an inlet Mach number of 1.71. The measured losses varied from 5 to 15 percent of the inlet stagnation pressure. The smallest loss was obtained for a passage in which separation on the convex surface was minimized through the introduction of a favorable pressure gradient" (p. 1).

Memorandum presenting measurements made in the transonic speed ranges of the static-pressure position error at a distance of 0.96 chord ahead of the wing tip of both the 8-percent-thick-wing and the 10-percent-thick-wing X-1 airplanes, and at a point 0.6 maximum fuselage diameter ahead of the fuselage nose of the X-1 airplanes. Results regarding the accuracy of pitot-static heads, static-pressure error of wing-tip installation, static-pressure error of the fuselage-nose installation, and error in total pressure are provided.