Flight Tests of Dive-Recovery Flaps on an XP-51 Airplane (open access)

Flight Tests of Dive-Recovery Flaps on an XP-51 Airplane

Report presenting a flight investigation made to determine the effectiveness of dive-recovery flaps installed on the XP-51 airplane as a safety device for recovery from contemplated terminal-velocity dives. The flap installation is described and results are presented of measurements obtained during stick-free pull-ups and pull-outs made by deflecting the dive-recovery flaps to two selected values of flap angle .
Date: May 1945
Creator: Beeler, De E. & Williams, Walter C.
System: The UNT Digital Library
Comparison of the Knock-Limited Performance of Triptane With 23 Other Purified Hydrocarbons (open access)

Comparison of the Knock-Limited Performance of Triptane With 23 Other Purified Hydrocarbons

"The knock-limited performance of blends containing General Motors triptane in S reference fuel and in an S plus M base fuel was determined in 17.6, F-3, F-4, and full-scale (single cylinder) engines. The results obtained are presented and are compared with published data from similar tests of 12 aromatics, 10 paraffins (including highly purified triptane), and 2 olefins. The comparison of fuels - which is based on a consideration of (a) antiknock blending sensitivity, (b) lead susceptibility, (c) temperature sensitivity, and (d) comparison of small-scale and full-scale engine data - is presented by means of bar graphs" (p. 1).
Date: May 1945
Creator: Branstetter, J. Robert
System: The UNT Digital Library
Tests of Air Valves for Intermittent-Jet Engines at Speeds of 20 and 25 Cycles Per Second (open access)

Tests of Air Valves for Intermittent-Jet Engines at Speeds of 20 and 25 Cycles Per Second

Report discussing a study of automatic nonreturn air valves for use in an intermittent-jet engine. Four valve-spring materials, three valve-grill materials, and five types of valves were used. Valve A, which was made out of aluminum, was found to perform the best and last the longest.
Date: May 8, 1945
Creator: Bressman, Joseph R. & McCready, Robert J.
System: The UNT Digital Library
Relation Between Fuel Economy and Crank Angle for the Maximum Rate of Pressure Rise (open access)

Relation Between Fuel Economy and Crank Angle for the Maximum Rate of Pressure Rise

Report discussing an investigation to determine whether the crank angle for maximum rate of pressure rise can be used to indicate maximum-economy spark advance. Information about spark-advance tests at constant inlet-air pressure and fuel-air-ratio test results are provided.
Date: May 21, 1945
Creator: Cook, Harvey A. & Brightwell, Virginia L.
System: The UNT Digital Library
A correlation of the effects of compression ratio and inlet-air temperature on the knock limits of aviation fuels in a CFR engine 1 (open access)

A correlation of the effects of compression ratio and inlet-air temperature on the knock limits of aviation fuels in a CFR engine 1

Report presenting a method of correlating the effects of compression ratio and inlet-air temperature on the knock limits of aviation fuels. Knock-limited performance tests of several fuels were run to check the method.
Date: May 1945
Creator: Evvard, John C. & Branstetter, J. Robert
System: The UNT Digital Library
Flight Investigation of the Variation of Drag Coefficient With Mach Number for the Bell P-39N-1 Airplane (open access)

Flight Investigation of the Variation of Drag Coefficient With Mach Number for the Bell P-39N-1 Airplane

Report presenting an investigation of the effect of compressibility on the drag of a Bell P-39N-1 airplane in flight as part of a drag study on several high-speed airplanes for a range of Mach numbers.
Date: May 1945
Creator: Gasich, Welko E. & Clousing, Lawrence A.
System: The UNT Digital Library
Flight Tests of an SB2C-3 Airplane With a Production and Tilted Propeller Axis (open access)

Flight Tests of an SB2C-3 Airplane With a Production and Tilted Propeller Axis

Report discussing the changes in static longitudinal stability due to tilting the propeller axis of an SB2C-3 airplane downward. Tilting the propeller was found to be beneficial for stability, but only if the pilot was in a forward center-of-gravity position with a tilted engine. Installing a tilted engine reduced trim forces due to the changes in power up to 25 percent.
Date: May 1945
Creator: Goranson, R. Fabian
System: The UNT Digital Library
Measurement of Flying Qualities of a DeHavilland Mosquito F-8 Airplane (AAF No. 43-334960) 1: Lateral and Directional Stability and Control Characteristics (open access)

Measurement of Flying Qualities of a DeHavilland Mosquito F-8 Airplane (AAF No. 43-334960) 1: Lateral and Directional Stability and Control Characteristics

The data presented have no bearing on performance characteristics of airplane, which were considered exceptionally good in previous tests. Some of the undesirable features of lateral and directional stability and control characteristics of the F-8 are listed. Directional stability, with rudder fixed, did not sufficiently restrict aileron yaw; rudder control was inadequate during take-off and landing, and was insufficient to fly airplane with one engine; in clean condition, power of ailerons was slightly below minimum value specified; it was difficult to trim airplane in rough air.
Date: May 1945
Creator: Gray, W. E., Jr.; Talmage, D. B. & Crane, H. L.
System: The UNT Digital Library
A comparison of analytically and experimentally determined isothermal pressure losses in a heat-exchanger installation (open access)

A comparison of analytically and experimentally determined isothermal pressure losses in a heat-exchanger installation

The results of this analysis indicate that isothermal pressure losses can be predicted analytically in the type of ducting system which may be broken down into the elementary forms of elbows, diffusers, and straight ducts for which pressure-loss data are published.
Date: May 1945
Creator: Hillendahl, Wesley H.
System: The UNT Digital Library
Performance Selection Charts for Gliders and Twin-Engine Tow Planes (open access)

Performance Selection Charts for Gliders and Twin-Engine Tow Planes

Report presenting performance charts for gliders and twin-engine tow planes with different degrees of aerodynamic and structural refinement. The glider charts display the gliding angle, useful load, stalling speeds, power required for level flight at various speeds, and power required for level flight while climbing at various speeds. The tow-plane charts show the stalling speeds, power required for level flight at various speeds, and power required for level flight while climbing at various speeds.
Date: May 1945
Creator: Ivey, H. Reese; Fitch, G. M. & Schultz, Wayne F.
System: The UNT Digital Library
Preliminary Investigation of Supersonic Diffusers (open access)

Preliminary Investigation of Supersonic Diffusers

Report presenting the deceleration of air from supersonic velocities in channels. A normal shock in the diverging part of the diffuser is probably necessary for stable flow, and ways of minimizing the intensity of this shock have been developed.
Date: May 1945
Creator: Kantrowitz, Arthur & Donaldson, Coleman duP.
System: The UNT Digital Library
A Method for Correlating the Cooling Data of Liquid-Cooled Engines and Its Application to the Allison V-3420-11 Engine (open access)

A Method for Correlating the Cooling Data of Liquid-Cooled Engines and Its Application to the Allison V-3420-11 Engine

Report discussing a study of the heat-transfer processes in liquid-cooled engines, an equation that has been developed based on the testing, and additional tests on an Allison V-3420-11 engine to determine the accuracy of the equation and the cooling characteristics of the engine. The equation was found to predict heat rejection to a coolant with good accuracy.
Date: May 1945
Creator: Kinghorn, George F.; Schroeder, Albert H. & Hagginbothom, William K., Jr.
System: The UNT Digital Library
Investigation of Methods of Supporting Single-Thickness Specimens in a Fixture for Determination of Compressive Stress-Strain Curves (open access)

Investigation of Methods of Supporting Single-Thickness Specimens in a Fixture for Determination of Compressive Stress-Strain Curves

"An investigation was made of the methods of supporting single-thickness specimens of aluminum-alloy sheet material in a fixture for determination of compressive stress-strain curves. The specimens were supported in the fixture by rollers, offset-grooved plates, opposite-grooved plates, flat brass plates, or flat wooden plates. The investigation also showed that the compression fixture, the specimen support, and the single-thickness specimens must be accurately made in order to obtain accurate stress-strain curves consistently" (p. 1).
Date: May 1945
Creator: Kotanchik, Joseph N.; Woods, Walter & Weinberger, Robert A.
System: The UNT Digital Library
The Effect of Six Aromatic Amines on the Preignition-Limited Performance of 28-R Aviation Fuel in a CFR Engine (open access)

The Effect of Six Aromatic Amines on the Preignition-Limited Performance of 28-R Aviation Fuel in a CFR Engine

Report discussing the results of testing on the suitability of six aromatic amines as fuel additives. Antiknock effectiveness, availability, physical properties, and chemical properties for knock tests were explored. The six aromatic amines were xylidines, cumidines, N-methylxylidines, N-methylcumidines, N-methylaniline, and N-methyltoluidine in 28-R aviation fuel.
Date: May 12, 1945
Creator: Male, Donald W.
System: The UNT Digital Library
An Experimental Investigation of Rectangular Exhaust-Gas Ejectors Applicable for Engine Cooling (open access)

An Experimental Investigation of Rectangular Exhaust-Gas Ejectors Applicable for Engine Cooling

Report presenting an experimental investigation of rectangular exhaust-gas ejector pump to provide data that would serve as a guide to the design of ejector applications for aircraft engines with marginal cooling. With a decrease in the quantity of air pumped and an increase in the length of an ejector, the ejector pressure rise increases to optimum values. Results regarding straight ejectors, diffuser ejectors, curved ejectors, ejector aspect ratio, divided ejectors, multistage ejectors, and nozzle-exit effects are provided.
Date: May 1945
Creator: Manganiello, Eugene J. & Bogatsky, Donald
System: The UNT Digital Library
Engine Tests of Pressurized Shunt-Type Cooling Systems for a Liquid-Cooled Engine (open access)

Engine Tests of Pressurized Shunt-Type Cooling Systems for a Liquid-Cooled Engine

Report presenting tests conducted to determine the performance of two pressurized shunt-type cooling systems for liquid-cooled aircraft engines using a mixture of 30 percent AN-E-2 ethylene glycol and 70 percent water as the coolant. Results regarding effect of engine speed on coolant-flow rate, effect of expansion-tank pressure on coolant-flow rate, relation between pump-inlet pressure and expansion-tank pressure, variation of coolant-flow rate with pump-inlet pressure, flow rate through the shunt lines, effect of coolant-flow rate on pressure drop, effect of venturi on performance of the cooling system, and the system operating experience are provided.
Date: May 1945
Creator: Manganiello, Eugene J.; Lundin, Bruce T. & Povolny, John H.
System: The UNT Digital Library
Effect of Engine-Operating Variables and Internal Coolants on Spark-Advance Requirements of a Liquid-Cooled Cylinder (open access)

Effect of Engine-Operating Variables and Internal Coolants on Spark-Advance Requirements of a Liquid-Cooled Cylinder

"Tests were conducted to determine the effect of engine-operating variables and internal coolants on spark-advance requirements of a single cylinder from a 12-cylinder liquid-cooled engine for maximum take-off power and maximum cruise economy. The effects of fuel-air ratio, engine speed, air flow (charge density), mixture temperature, and internal coolants on peak-power (optimum) spark advance were investigated. In addition, tests were conducted to determine the effect of spark advance on the knock-limited engine performance at several mixture temperatures for conditions simulating take-off, high-power cruise, and low-power cruise" (p. 1).
Date: May 18, 1945
Creator: Pfender, John F.; Dudugjian, Carl & Lietzke, A. F.
System: The UNT Digital Library
The Effect of Mach Number on the Aerodynamic Characteristics of a Single-Engine Pursuit Airplane as Determined From Tests of a 1/3-Scale Model (open access)

The Effect of Mach Number on the Aerodynamic Characteristics of a Single-Engine Pursuit Airplane as Determined From Tests of a 1/3-Scale Model

Report discussing the effects of Mach number on the aerodynamic characteristics of an Allison powered single-engine pursuit airplane. Information about the lift, drag, pitching-moment characteristics, stability, tail effectiveness, and elevator effectiveness with Mach number is provided.
Date: May 3, 1945
Creator: Robinson, Robert C. & Jessen, Henry
System: The UNT Digital Library
An Investigation of a Thermal Ice-Prevention System for a C-46 Cargo Airplane 5: Effect of Thermal System on Airplane Cruise Performance (open access)

An Investigation of a Thermal Ice-Prevention System for a C-46 Cargo Airplane 5: Effect of Thermal System on Airplane Cruise Performance

Report presenting flight tests conducted to evaluate the effect of a thermal ice prevention system on the aerodynamic performance of a C-46 cargo airplane. The installation of the thermal ice-prevention system was found to reduce the indicated airspeed by about 6 miles per hour. Results regarding the overall performance change resulting from the installation of the thermal system, reduction of power attributed to heat-exchanger exhaust-gas back pressure, reduction of power attributed to the internal and external drag of the thermal system, and the additional airplane gross weight attributed to the thermal system are provided.
Date: May 1945
Creator: Selna, James
System: The UNT Digital Library
An Investigation of a Thermal Ice-Prevention System for a C-46 Cargo Airplane 6: Dry-Air Performance of Thermal System at Several Twin- and Single-Engine Operating Conditions at Various Altitudes (open access)

An Investigation of a Thermal Ice-Prevention System for a C-46 Cargo Airplane 6: Dry-Air Performance of Thermal System at Several Twin- and Single-Engine Operating Conditions at Various Altitudes

Report presenting flight tests to establish the dry-air-performance characteristics of a thermal ice-prevention system at various operating conditions and altitudes. Results regarding twin-engine tests and single-engine tests of characteristics such as skin temperatures and location of heating are provided.
Date: May 1945
Creator: Selna, James & Kees, Harold L.
System: The UNT Digital Library
Fuel-Evaporation Loss as Determined by the Change in the Specific Gravity of the Fuel in an Aircraft Fuel Tank (open access)

Fuel-Evaporation Loss as Determined by the Change in the Specific Gravity of the Fuel in an Aircraft Fuel Tank

Report discusses the results of an investigation to determine the feasibility of using the change in the specific gravity of fuels in aircraft fuel tanks to measure fuel-vaporization loss. Six fuels were tested via fuel-distillation tests and simulated-flight tests. An equation based on the specific gravity of the fuel is also described.
Date: May 1945
Creator: Stone, Charles S. & Kramer, Walter E.
System: The UNT Digital Library
An Electromagnetic-Analogy Method of Solving Lifting-Surface-Theory Problems (open access)

An Electromagnetic-Analogy Method of Solving Lifting-Surface-Theory Problems

Report presenting a method for making lifting-surface calculations by means of magnetic measurements of an electromagnetic-analogy model. The method is based on the perfect analogy between the strength of the magnetic field around a conductor and the strength of the induced-velocity field around a vortex.
Date: May 1945
Creator: Swanson, Robert S. & Crandall, Stewart M.
System: The UNT Digital Library
Effect of Oil Flow to Piston on Piston-Ring Sticking and Oil Consumption in a Single-Cylinder Engine (open access)

Effect of Oil Flow to Piston on Piston-Ring Sticking and Oil Consumption in a Single-Cylinder Engine

Report presenting an investigation to determine the effect of the amount of oil flow to the piston on the ring-sticking characteristics of a piston and ring assembly and on the engine oil consumption. Results regarding the blow-by, lubrication, oil consumption, and method of supplying oil are provided.
Date: May 1945
Creator: Tauschek, Max J.; Corrington, Lester C. & Meigs, John B.
System: The UNT Digital Library
Wind-Tunnel Tests of the 0.15-Scale Powered Model of the Fleetwings XBTK-1 Airplane: Longitudinal Stability and Control (open access)

Wind-Tunnel Tests of the 0.15-Scale Powered Model of the Fleetwings XBTK-1 Airplane: Longitudinal Stability and Control

"An investigation was made of the static longitudinal stability, and control and stall characteristics of XBTK-1 dive bomber. Results indicate that the longitudinal stability will probably be satisfactory for all contemplated flight conditions at the rear-most CG location with elevator both fixed and free. Power effects were small. Sufficient elevator control will be available to trim in any flight condition above the ground" (p. 1).
Date: May 1945
Creator: Weil, Joseph & Boykin, Rebecca I.
System: The UNT Digital Library