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Aerodynamic Forces and Moments on a Large Ogive-Cylinder Store at Various Locations Below the Fuselage Center Line of a Swept-Wing Bomber Configuration at a Mach Number of 1.61

Description: A supersonic wind-tunnel investigation on store interference has been conducted in the Langley 4- by 4-foot supersonic pressure tunnel at a Mach number of 1.61. Forces and moments were measured on a large ogive-cylinder store in the presence of a 45 deg swept-wing-fuselage bomber configuration for a number of store locations below the fuselage center line. Results of the investigation show that large variations of store lift, drag, and pitch occur with changes in store or airplane angle of attack, store vertical location, and store horizontal location. The variation of the store forces and moments with respect to the chordwise location of the wing plan form indicates that the wing is a large factor in producing the interference loads on the store. Comparison of data for underfuselage and underwing store locations at an angle of attack of 0 deg showed maximum store drag interferences of similar magnitudes, but showed considerably smaller maximum interference on store lift an pitching moments for underfuselage store locations.
Date: January 14, 1957
Creator: Morris, O. A.

Investigation of Control Effectiveness and Stability Characteristics of a Model of a Low-Wing Missile with Interdigitated Tail Surfaces at Mach Numbers of 2.29, 2.97, and 3.51

Description: A brief investigation of the longitudinal stability and control effectiveness at supersonic speeds of a model of a low-wing missile with interdigitated tail surfaces was made in the Langley Unitary Plan wind tunnel. The data were obtained at Mach numbers M of 2.29, 2.97, and 3.51 for Reynolds number (based on the mean geometric chord of the wing) of 1.15 x 10(exp 6), 1.14 x 10(exp 6), and 1.11 x 10(exp 6), respectively. Data were obtained for three settings of the longitudinal control surfaces: with deflection of all surfaces, with deflection of the lower surfaces only, and with all surfaces undeflected. Directional stability data were obtained at M=3.51 for angles of attack of approximately 0 deg and 10 deg. These data, with summary data and typical schlieren photographs, are presented with only a brief analysis. The data indicate that the controls are effective throughout the Mach number range and lift-coefficient range (CL = -0.15 to 0.7, approximately) of the tests. There is a severe break in the pitching-moment curve at M=2.29 which might result in a pitch-up condition in flight, and also a large forward movement of the aerodynamic center with increasing Mach number that produces neutral longitudinal stability at M=3.51 for the moment center used in this investigation. The model was directionally unstable at M=3.51; however, the level of directional stability was about the same for 0 deg and 10 deg angles of attack.
Date: July 14, 1958
Creator: Presnell, John G., Jr.

Investigation of a 1/4 scale model of the Republic F-105 airplane in the Langley 19-foot pressure tunnel: Longitudinal stability and control and horizontal-tail hinge-moment and normal-force characteristics of the model equipped with a drooped supersonic-type elliptical wing-root inlet

Description: Report presenting testing of the Republic F-105 at low speeds to determine the results of additional longitudinal stability tests of measurements of the hinge moments and normal force of the all-movable horizontal tail on a model equipped with a supersonic-type elliptical wing-root inlet.
Date: November 14, 1955
Creator: Cancro, Patrick A. & Kelly, H. Neale

Experimental and Analytical Study of Balanced-Diaphragm Fuel Distributors for Gas-Turbine Engines

Description: A method of distributing fuel equally to a plurality of spray nozzles in a gas-turbine engine by means of balanced-diaphragm fuel distributors is presented. The experimental performance of three of eight possible distributor arrangements are discussed. An analysis of all eight arrangements is included. Criterions are given for choosing a fuel-distributor arrangement to meet specific fuel-system requirements of fuel-distribution accuracy, spray-nozzle pressure variations, and fuel-system pressures. Data obtained with a model of one distributor arrangement indicated a maximum deviation from perfect distribution of 3.3 percent for a 44 to 1 range (19.5 to 862 lb/hr) of fuel-flow rates. The maximum distributor pressure drop was 125 pounds per square inch. The method used to obtain the required wide range of flow control in the distributor valves consisted in varying the length of a constant-area flow path.
Date: August 14, 1950
Creator: Straight, David M. & Gold, Harold

Preliminary analysis of hydrogen-rich hypersonic ramjet operation

Description: 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.
Date: January 14, 1958
Creator: Breitwieser, Roland & Morris, James F.

Experimental static aerodynamic forces and moments at high subsonic speeds on a canard missile during simulated launching from the midsemispan location of a 45 degree sweptback wing-fuselage-pylon combination at zero sideslip

Description: 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.
Date: January 14, 1957
Creator: Alford, William J., Jr. & King, Thomas J., Jr.

Maximum-lift investigation at Mach numbers from 0.05 to 1.20 of a wing with leading edge swept back 42 degrees

Description: Report presenting an investigation at subsonic and transonic speeds to determine the aerodynamic characteristics of three geometrically similar wings with 42 degree sweepback of the leading edge, aspect ratio 4, taper ratio 0.625, and NACA 64(sub)1-112 airfoils. The lift, drag, and pitching-moment characteristics are provided.
Date: February 14, 1950
Creator: Turner, Thomas R.

Pressure distributions on the blade sections of the NACA 10-(3)(049)-033 propeller under operating conditions

Description: A report in a series of five that present unanalyzed pressure data obtained in tests of five full-scale propellers with NACA 16-series blade sections. Pressure distributions on the blade sections were measured under operating conditions to determine the aerodynamic characteristics of each blade section. This particular report presents information for nine radial stations of the NACA 10-(3)(049)-033 propeller.
Date: February 14, 1950
Creator: Gray, W. H. & Hunt, Robert M.

Preliminary investigation of the supersonic flow field downstream of wire-mesh nozzles in a constant-area duct / Lawrence I. Gould

Description: An investigation was conducted in a 3.4- by 3.4-inch duct to determine the characteristics of the supersonic flow downstream of four wire-mesh screen nozzles with nominal design Mach numbers in the range between 1.97 and 2.58. Two types of disturbances were observed in the flow field: a fine network of interacting expansion and compression waves which were formed immediately downstream of the screens and appeared to dissipate within 25 to 40 wave intersections; and relatively strong oblique shock waves that originated at the junctions of the screens and the walls and were reflected throughout the length of the duct. Regions of fairly uniform flow were found to exist. The total-pressure loss across the screens varied from 22 percent at Mach number 1.58 to 43 percent at Mach number 2.06.
Date: August 14, 1951
Creator: Gould, Lawrence I

Description and investigation of a dynamic model of the XH-17 two-blade jet driven helicopter

Description: 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.
Date: March 14, 1951
Creator: Brooks, George W. & Sylvester, Maurice A.

Time histories of the aerodynamic loads on the vertical and horizontal tail surfaces of a jet-powered bomber airplane during sideslip maneuvers at approximately 20,000 feet

Description: Report presenting time histories of the aerodynamic loads on the vertical and horizontal tail surfaces of a jet-powered bomber airplane (B-45A) in sideslip maneuvers. Information about maximum measured rudder and fin loads, maximum total vertical-tail load, horizontal-tail-load dissymmetry, maximum elevator loads, and elevator-load dissymmetry is provided.
Date: March 14, 1951
Creator: Cooney, T. V. & McGowan, William A.