Report presenting an investigation of the feasibility of modifying the transient portion of the stick force in abrupt maneuvers in order to eliminate inadvertent normal-acceleration overshoots. The modification consists of additional stick force proportional to a quantity which leads the normal acceleration. The characteristics introduced by the inclusion of the force were considered to be very desirable by pilots.

Flight and ground investigations have been made to compare an exhaust-ejector installation with a standard exhaust-collector-ring installation on air-cooled aircraft engines in a twin-engine airplane. The ground investigation allowed that, whereas the standard engine would have overheated above 600 horsepower, the engine with exhaust ejectors cooled at take-off operating conditions at zero ram. The exhaust ejectors provided as much cooling with cowl flaps closed as the conventional cowl flaps induced when full open at low airspeeds. The propulsive thrust of the exhaust-ejector installation was calculated to be slightly less than the thrust of the collector-ring-installation.

"An investigation of the nature of the flow field behind a rectangular circular-arc wing has been conducted in the Langley 9-inch supersonic tunnel. Pitot- and static-pressure surveys covering a region of flow behind the wing have been made together with detailed pitot surveys throughout the region of the wake. In addition, the flow direction has been measured using a weathercocking vane measurements. Theoretical calculations of the variation of both downwash and sidewash with angle of attack using Lagerstrom's superposition method have been made" (p. 1).

"An investigation of the nature of the flow field behind a rectangular wing of circular arc cross section has been conducted in the Langley 9-inch supersonic tunnel. Pitot- and static-pressure surveys covering a region of flow behind the wing have been made together with detailed pitot surveys throughout the region of the wake. In addition, the flow direction has been measured by means of a weathercocking vane. Theoretical calculations have been made to obtain the variation of both downwash and sidewash with angle of attack by using the superposition method of Lagerstrom, Graham, and Grosslight" (p. 1).

Tests to evaluate the effect of a conical windshield on the drag of a bluff body at supersonic speeds were performed for the following configurations: a sharp nose fuselage with stabilizing fins,a blunt nose fuselage with a hemispherical shape, and a blunt nose fuselage with a conical point. Results of the drag coefficient are described at Mach 1.0 and the greatest Mach number of 1.37.

Report presenting an investigation at high subsonic speeds to determine the static aerodynamic forces and moments on a canard missile model during simulated launching from the midsemispan location of a 45 degree sweptback wing-fuselage-pylon combination. Significant variations in all the aerodynamic components were noted with changes in chordwise location of the missile. Results regarding force and moment characteristics and effects of angle of attack and Mach number are provided.

Report presenting a discussion of the aerodynamic forces and moments on inclined bodies of revolution. An approximate theory to allow for the effects of viscosity is developed and applied. Results regarding the variation of lift and pitching moment, and center of gravity are provided.

Report presenting an investigation to determine the aerodynamic characteristics in sideslip of a triangular wing of aspect ratio 2.04 in combination with a body of fineness ratio 12.5 and a vertical tail surface. The body combined with the triangular plan-form wing caused no significant changes in the lift characteristics of the wing and only a 1-percent decrease in the static margin. Results regarding the longitudinal characteristics, lateral and directional characteristics, and estimation of tail and rudder effectiveness are provided.

Report presenting flight tests conducted between Mach numbers of 0.9 to 1.8 over a range of Reynolds numbers to determine the zero-lift drag and some rolling-effectiveness characteristics of a proposed long-range, supersonic, ground-to-ground missile. Results regarding the longitudinal trim, drag, rolling effectiveness, and instability due to roll are provided.

"An investigation is being conducted to determine the altitude performance characteristics of the Nene II engine and its components. The present paper presents preliminary results obtained using a jet nozzle of 18.41 inches in diameter, giving an area equal to 96.4 percent of the area of the standard jet nozzle of this engine. The test results presented are for conditions simulating altitudes from seal level to 50,000 feet and ram-pressure ratios from 1.00 to 2.70. The ram pressure ratios correspond to flight Mach numbers between zero and 1.28" (p. 1).

Report presenting testing using a Douglas D-558-I airplane to determine the effect of wing vortex generators on some of the undesirable handling characteristics of aircraft flying at hypercritical speeds. The effects on buffeting, lateral unsteadiness, change in trim, and loss of control effectiveness were the primary objectives.

"A study has been made of the variation of seaplane hull weight with length-beam ratio in a systematic series of hulls designed for constant gross weight and similar spray characteristics. It is found that increases in the length-beam ratio bring about small reductions in the hull weight if it is assumed that seaplanes having the same weight and bottom shape will be designed for the same load factor. A short discussion is also given to show the reduction in load factor that may occur with high length-beam ratios" (p. 1).

Report presenting a wind-tunnel investigation to determine the effects of leading-edge radius and maximum thickness-chord ratio on the variation with Mach number of the aerodynamic characteristics of several thin symmetrical NACA 4-digit-series airfoil sections. The variations with Mach number of the lift, drag, and pitching moment for a 4-percent-chord-thick airfoil section are not significantly affected by a change of leading-edge radius from 0.18 to 0.53 percent of the chord.

Report presenting a program to investigate the aerodynamic characteristics of thin delta wings with symmetrical double-wedge sections in the hypersonic tunnel at a Mach number of 6.9. A family of 5-percent-thick lifting wings with semiapex angles were tested over a range of angles of attack. Results regarding lift and drag characteristics, center of pressure and moment coefficient, Schileren photographs, and surface film flow studies are provided.

"Two 3-blade 10-foot propellers were operated in front of a liquid-cooled engine nacelle. The propellers differed only in pitch distribution; one had normal distribution (nearly constant pitch for a blade angle of 15 degrees at 0.75 radius), and the other had the pitch of the tip sections decreased with respect to that for the shank sections (blade angle of 35 degrees for nearly constant pitch distribution). Propeller blade angles at 0.75r from 15 degrees to sixty degrees, corresponding to design speeds up to 500 miles per hour, were investigated" (p. 327).

"Results are reported of current studies at the Forest Products Laboratory to develop a metal-bonding adhesive with greater resistance to temperatures up to 600 degrees Fahrenheit that is easier to use than present ones. Most promising is a formulation of phenol and epoxy resins modified with hexamethylenetetramine and supplied for use as a dry tape supported on a glass-mat base" (p. 1).

Results are presented of an experimental and theoretical investigation of the growth of transverse velocity disturbances in the shear region caused by a flame in a duct. In the theoretical stability analysis, a flow field arising from a flame in a duct was analyzed. The flow was neutrally stable to symmetric disturbances and unstable to antisymmetric ones. In the experimental part of the program disturbances of various frequencies were imposed on a flame stabilized in a duct, and the effects were measured by shadow photography and photomultiplier-probe surveys.

Drag and longitudinal trim at low lift of the North American YF-100A airplane at Mach numbers from 0.76 to 1.77 as determined from the flight test of a 0.11-scale rocket model are presented herein. Also included are some longitudinal stability and some qualitative pitch-damping data.

Report presenting drag data obtained from flight tests of two scale rocket-powered models of the Chance Vought XF8U-1 airplane. Results regarding the minimum drag coefficient and effect of nose modifications are provided.

"An investigation has been completed in the Langley 20-foot free-spinning tunnel on a 1/24-scale model of the Grumman F11F-1 airplane to determine its spin and recovery characteristics. An interim report, Research Memorandum SL55G20, was published earlier and the present report concludes the presentation of results of the investigation. Primarily, the present report presents results obtained with engine gyroscopic moments simulated on the model. Also, the current results were obtained with a revised larger vertical tail recently incorporated on the airplane" (p. 1).

Report presenting testing to determine the longitudinal stability characteristics of the TX-17, the "Short Seven", and the TX-21 special weapons. Dynamic and static stability data are provided for a range of Mach numbers and stagnation-pressure levels.

Report discussing findings on net thrust, fuel flow, and related performance indices for hydrogen-rich operation of nacelle-type and submerged ramjet engines at various Mach numbers. Testing concluded that the system could be helpful in a flight path involving acceleration from low to high flight speeds. Some trends of the effect of the operation conditions are noted, but no conclusions are drawn because of the preliminary nature of the report.

Report presenting a description and results of an investigation of a model of the XH-17 two-blade, jet-powered helicopter. Tests were made with a standard configuration and with several modifications, including varying the size of blade counterweights, changing the control stiffness and chordwise bending stiffness of the blades, and varying the pylon and undercarriage damping and spring constants. Results regarding flutter testing, ground-vibration tests, and three-per-revolution rotor-blade unsymmetric bending oscillations are provided.

From Summary: "An investigation of a 1/21-scale model of the Chance Vought F7U-3 airplane in the combat-loading condition has been conducted in the Langley 20-foot free-spinning tunnel. The recovery characteristics of the model were determined by use of spin-recovery rockets for the erect and inverted spinning condition. The rockets were so placed as to provide either a yawing or rolling moment about the model center of gravity. Also included in the investigation were tests to determine the effect of simulated engine thrust on the recovery characteristics of the model."