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Wind-tunnel tests of single- and dual-rotating pusher propellers having from three to eight blades

Description: Report presenting tests of 10-foot-diameter, single- and dual-rotating pusher propellers with three to eight blades that were conducted in the 20-foot propeller research tunnel as a continuation of previous investigations of tractor propellers. The propellers were mounted at the rear end of a streamline body in spinners that covered the hubs and part of the shanks. The effects as compared to previous testing differed only in degree of effect size.
Date: February 1942
Creator: Gray, W. H.
Partner: UNT Libraries Government Documents Department

An investigation of aircraft heaters 17: experimental inquiry into steady state unidirectional heat-meter corrections

Description: Report divided into two sections. One discusses a correction that must be applied to a heat meter when it is used at temperatures other than temperatures at which it was calibrated. The other section contains the results of an application of the two methods of correcting the heat-transfer rates for contact and heat-meter resistance to experimental data.
Date: August 1944
Creator: Boelter, L. M. K.; Poppendiek, H. F. & Gier, J. T.
Partner: UNT Libraries Government Documents Department

An investigation of aircraft heaters 15: the emissivity of several materials

Description: Report presenting a determination of the mean effective emissivity as a function of temperature for the surfaces of several metals and insulating materials. A description and discussion of the measuring technique is presented. The results are plotted on a variety of graphs.
Date: January 1944
Creator: Boelter, L. M. K.; Bromberg, R. & Gier, J. T.
Partner: UNT Libraries Government Documents Department

An investigation of aircraft heaters 14: an air and heat flow analysis of a ram-operated heater and duct system

Description: Report presenting a method of graphical analysis that allows for the prediction of the thermal and aerodynamic performance of a ram-operated heater and duct system, for cabin heating or wing de-icing, at any altitude and airplane speed. Performance can be predicted from the isothermal total pressure drop across the components of the duct system at several ventilating air rates and the thermal output of the heater at various air and exhaust gas rates.
Date: March 1944
Creator: Boelter, L. M. K.; Morrin, E. H.; Martinelli, R. C. & Poppendiek, H. F.
Partner: UNT Libraries Government Documents Department

An investigation of aircraft heaters 24: the heat meter in the transient state for unidirectional heat transfer

Description: Report describing the behavior of the heat meter when it is used in thermal circuits which are under the influence of transient potentials. Three scenarios are considered: a heat meter suddenly placed on a hot surface, a heat meter mounted on the interior surface of the cabin wall of an uninsulated airplane climbing through air of decreasing temperature, and a heat meter mounted on the interior surface of the composite cabin wall of an airplane climbing through air of decreasing temperature.
Date: September 1944
Creator: Boelter, L. M. K.; Poppendiek, H. F.; Dunkle, R. V. & Gier, J. T.
Partner: UNT Libraries Government Documents Department

Measurements in flight of the pressure distribution on the right wing of a P-39N-1 airplane at several values of Mach number

Description: Report presenting pressure-distribution measurements made on the right wing of a P-39N-1 airplane at values of Mach number up to 0.80. A considerable portion of the lift was carried by components of the airplane other than the wings, and the proportion carried by the wing varies considerably with Mach number. Results regarding the variation of wing loads and moments with Mach number, internal wing pressure, and airplane lift-curve slope are provided.
Date: April 1945
Creator: Clousing, Lawrence A.; Turner, William N. & Rolls, L. Stewart
Partner: UNT Libraries Government Documents Department

Wind-tunnel tests of four full-scale seaplane floats

Description: Report presenting wind tunnel testing of four full-scale seaplane floats to determine the aerodynamic characteristics of the floats and to evaluate several drag-reducing refinements. Four floats were investigated; two differed only in external details like flush rivets, while one was the type used on twin-float installations. The variation of lift, drag, and pitching moment with pitch angle are presented for each float.
Date: July 1943
Creator: Conway, Robert N. & Maynard, Julian D.
Partner: UNT Libraries Government Documents Department

Quantitative analysis for aromatic amines in aviation fuels by ultraviolet spectrophotometry

Description: From Summary: "A method of quantitative analysis for individual aromatic amines or mixtures of aromatic amines in hydrocarbon fuel blends by spectrophotometric measurement of ultraviolet-light absorption is presented. The effect of the precision of the spectrophotometric measurements, the purity of the aromatic amine, photochemical decomposition of the amine, and the composition of the fuel on the accuracy of the analysis is discussed and the results of tests of the precision of the procedure are given."
Date: November 1945
Creator: Tischler, Adelbert O.
Partner: UNT Libraries Government Documents Department

Performance tests of NACA type A finned-tube exhaust heat exchanger

Description: Report presenting tests to determine the thermal and pressure-drop performance and durability of a cross-flow, internally finned, tubular exhaust-heat exchanger. The test covered a range of exhaust-gas flows, cooling-air flows, and exhaust-gas temperatures.
Date: August 1944
Creator: Reuter, J. George & Manson, S. V.
Partner: UNT Libraries Government Documents Department

Wind-tunnel vibration tests of dual-rotating propellers

Description: Report presenting vibration tests of six- and eight-blade tractor and seven- and eight-blade pusher dual-rotating propellers conducted in the 16-foot high-speed tunnel to determine the severity of vibrations excited by blade passages. Measurements of vibratory stresses were made for engine-speed ranges at low, intermediate, and high engine powers. Few vibrations caused by blade passages were detected, and those vibrations were not serious.
Date: September 1943
Creator: Miller, Mason F.
Partner: UNT Libraries Government Documents Department

Wind-tunnel vibration tests of a four-blade single rotating pusher propeller

Description: Report presenting vibration tests of a four-blade single-rotating propeller operating in a simulated pusher condition performed because the combination of wake and downwash behind a wing might provide serious excitation for reactionless vibrations of propellers with four or more blades. Measurements of propeller vibratory stress were made for various airspeeds, engine speeds, and engine powers.
Date: June 1943
Creator: Miller, Mason F.
Partner: UNT Libraries Government Documents Department

Preliminary flight research on an all-movable horizontal tail as a longitudinal control for flight at high Mach numbers

Description: Report presenting flight tests of an all-movable horizontal tail installed on a Curtiss XP-42 airplane due to its possible advantages as a longitudinal control at high Mach numbers. The elevator control was found to be unsatisfactory with the control arrangements tested.
Date: March 1945
Creator: Kleckner, Harold F.
Partner: UNT Libraries Government Documents Department

Flame-visibility tests with individual exhaust stacks

Description: Report presenting testing made on a Wright 1820-G single-cylinder engine to determine the effect of operating variables and the effect of shape and size of the exhaust stack on the visibility of exhaust gases for individual-stack installations. Flame damping was improved by decrease in nozzle-exit area, increase in stack length, and reduction in hydraulic diameter of the exhaust jets. Results regarding the characteristics of exhaust flames and damping of exhaust flames are provided.
Date: February 1944
Creator: Turner, L. Richard & Humble, Leroy V.
Partner: UNT Libraries Government Documents Department

Wind tunnel investigation of control surface characteristics 9: some analytical considerations and experimental test results for an internally balanced flap

Description: Report presenting an analysis of the probable aerodynamic section characteristics of a plain flap with various arrangements of internal balance. The results of the calculations previously obtained were found to be in agreement with the experiment. Some possible applications of the data to balancing tabs are also provided.
Date: July 1942
Creator: Sears, Richard I.
Partner: UNT Libraries Government Documents Department

Wind-tunnel investigation of control-surface characteristics 1: effect of gap on the aerodynamic characteristics of an NACA 0009 airfoil with a 30-percent-chord plain flap

Description: From Summary: "Tests have been made to determine the effect of a gap at the flap nose upon the aerodynamic section characteristics of an NACA 0009 airfoil with a plain flap and tab. The results are presented in the form of airfoil and flap section characteristics for several flap deflections, tab deflections, and for four sizes of gap."
Date: June 1941
Creator: Sears, Richard I.
Partner: UNT Libraries Government Documents Department

Full-scale wind-tunnel and flight tests of a Fairchild XR2K-1 airplane with a zap flap and upper-surface aileron-wing installation

Description: Report presenting testing of a Fairchild XR2K-1 airplane equipped with a wing having a full-span Zap flap and upper-surface ailerons in the full-scale wind tunnel and in flight to determine the characteristics of the flap and ailerons. Results regarding the lift, drag, and pitching-moment coefficients of the airplane and the aileron rolling, yawing, and hinge-moment coefficients were measured at various flap deflections are provided. Maximum rolling velocity and acceleration, yawing velocity, time lag in aileron response, and aileron control forces were also determined.
Date: March 1942
Creator: Clousing, L. A.; Lehr, Robert R. & O'Sullivan, William J.
Partner: UNT Libraries Government Documents Department

Wind-tunnel tests of single- and dual-rotating tractor propellers of large blade width

Description: Report presenting tests of 10-foot diameter, single- and dual-rotating tractor propellers with two to eight blades conducted in the 20-foot propeller-research tunnel. The blades were 50 percent wider than those used in previous investigations. Results regarding the effect of dual rotation and effect of solidity are provided.
Date: September 1942
Creator: Biermann, David; Gray, W. H. & Maynard, Julian D.
Partner: UNT Libraries Government Documents Department

The effect of cooling-air blowers on thrust power

Description: Report presenting an analysis of the effect of cooling-air blowers on thrust power using an assumed airplane. Results indicated that when aviation-engine heat exchangers are used above their design altitude, blowers may be used to give additional available pressure and to increase jet thrust. Results regarding airplane speed, altitude, fin width, physical significance of the heat cycle, and thermodynamic efficiency are provided.
Date: July 1944
Creator: Palmer, Carl B. & Brevoort, Maurice J.
Partner: UNT Libraries Government Documents Department

The effect of dead rise upon the high-angle porpoising characteristics of two planing surfaces in tandem

Description: Report presenting porpoising tests of three rudimentary models composed of two V-bottom planing surfaces in tandem and fitted with a tail plane. The upper and lower branches of the upper trim limit of stability were determined for three angles of dead rise and two depths of step.
Date: June 1943
Creator: Benson, James M. & Klein, Milton M.
Partner: UNT Libraries Government Documents Department

Effect of changing the stroke on air capacity, power output and detonation of a single-cylinder engine

Description: Report presenting an investigation of a special single-cylinder test engine constructed with provision for operation with three different lengths of piston stroke. Results regarding the air capacity of the engine, extent to which the spark must be retarded in order to prevent detonation, and brake mean effective pressure are provided.
Date: February 1945
Creator: Livengood, James C. & Eppes, James V. D.
Partner: UNT Libraries Government Documents Department

A method for studying piston friction

Description: From Introduction: "The purpose of this investigation was to develop a method for determining directly the friction force between the piston and cylinder of an internal combustion engine. The method consists in elastically mounting the cylinder barrel so that it can have a small motion parallel to its axis, and providing suitable means for recording its instantaneous displacement."
Date: March 1943
Creator: Forbes, J. E. & Taylor, E. S.
Partner: UNT Libraries Government Documents Department

A correlation of the effects of compression ratio and inlet-air temperature on the knock limits of aviation fuels in a CFR engine 2

Description: Report presenting the knock-limited performance of nine fuels comprising isolated members of four classes of hydrocarbons in the form of three-dimensional plots of fuel-air ratio, compression temperature, and compression-air density.
Date: June 1946
Creator: Alqusit, Henry E.; O'Dell, Leon & Evvard, John C.
Partner: UNT Libraries Government Documents Department

The determination of effective column length from strain measurements

Description: From Summary: "A method is presented for the experimental determination of the effective length of a column for which the end conditions are unknown by establishing the points of zero curvature from readings of strain gages distributed along the length of the column. Tests of four columns of different cross sections indicated that the proposed method gives satisfactory results even when there is considerable scatter in the strain-gage readings."
Date: June 1944
Creator: Schuette, Evan H. & Roy, J. Albert
Partner: UNT Libraries Government Documents Department

Design, selection, and installation of aircraft heat exchangers

Description: Report presenting a survey of aircraft heat exchangers in three parts: design, selection, and installation. Appendices give the physical properties of air, properties of standard atmosphere as defined by the Navy, Army, and NACA, and an impact-pressure chart.
Date: July 1943
Creator: Wood, George P. & Brevoort, Maurice J.
Partner: UNT Libraries Government Documents Department