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Preliminary report on flight tests of an airplane having exhaust-heated wings

Description: Report presenting testing of an airplane in icing conditions to determine the effect of exhaust heat applied to the wings as a means of preventing ice formations. Other ice-prevention equipment, including an exhaust gas-heated pitot-static head, hot-air-heated windshield, and an inflatable de-icer were also tested.
Date: April 1941
Creator: Rodert, Lewis A.; McAvoy, William H. & Clousing, Lawrence A.
Partner: UNT Libraries Government Documents Department

An analytical study of wing and tail loads associated with an elevator deflection

Description: From Introduction: "The present paper covers step 1 of the outlined investigation, includes methods of computing the variation of wing and tail loads, and gives numerical results of the application of the theory to the BT-9B airplane. Finally, theoretical formulas are developed and charts are given for computing the maximum increments of wing load, the down-tail load, and the up-tail load following a given elevator displacement."
Date: June 1941
Creator: Pearson, H. A. & Garvin, J. B.
Partner: UNT Libraries Government Documents Department

A flight investigation of the thermal properties of an exhaust heated wing de-icing system on a Lockheed 12-A airplane

Description: From Summary: "The thermal properties are presented for the exhaust heated wing de-icing system of a Lockheed 12-A airplane which has successfully prevented a wing icing in 25 hours of flying in various icing conditions. The quantities of heat supplied for de-icing of the wings under various conditions were measured and are presented. The distribution of temperatures above the ambient air temperature for the wing surface under various operating conditions are given."
Date: June 1941
Creator: Rodert, Lewis A. & Clousing, Lawrence A.
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

Aluminum-zinc-magnesium-copper casting alloys

Description: From Introduction: "This paper contains data on the mechanical properties of sand-cast test bars having a considerable range in zinc, magnesium, and copper content and more detailed data on the properties and foundry characteristics of an aluminum-zinc-magnesium-copper alloy having a preferred composition for high strength and ductility."
Date: July 1941
Creator: Kempf, L. W.
Partner: UNT Libraries Government Documents Department

A semi-rational criterion for unsymmetrical gust loads

Description: Report presenting a discussion of the problem of establishing a rational unsymmetrical gust load criterion from available data on gust structure and it is indicated that the problem cannot be solved at the present state of knowledge without more analysis.
Date: August 1941
Creator: Rhode, Richard V. & Pearson, Henry A.
Partner: UNT Libraries Government Documents Department

Wind-tunnel investigation of control-surface characteristics II : a large aerodynamic balance of various nose shapes with a 30-percent-chord flap on an NACA 0009 airfoil

Description: Report presenting testing of an NACA 0009 airfoil with a 30-percent-chord flap with a 49.5-percent flap-chord balance with various nose shapes and two gaps. The results indicated that the flap is overbalanced when deflected, regardless of nose shape. Results regarding lift, hinge moment of flap, drag, pitching moment, and effect of differential balancing tab are provided.
Date: August 1941
Creator: Sears, Richard I. & Hoggard, H. Page, Jr.
Partner: UNT Libraries Government Documents Department

Critical speeds and profile drag of the inboard sections of a conventional propeller

Description: Report presenting the section critical speeds and profile drags of the shank and hub sections of a propeller used on a current liquid-cooled-engine pursuit type of airplane. Results indicated that serious adverse compressibility effects can be expected at speeds of about 400 miles per hour. Suitable fairings for shank and hub sections were found to be necessary for maximum propulsive efficiency.
Date: September 1941
Creator: Luoma, Arvo A.
Partner: UNT Libraries Government Documents Department

Dynamic stress calculations for two airplanes in various gusts

Description: Report presenting a series of calculations made to determine the probable dynamic wing stress of two large airplanes in atmospheric gusts. The results indicate that in both isolated and repeated gusts of probable occurrence, the dynamic overstress is about 10 percent when referred to the present static design standard.
Date: September 1941
Creator: Pierce, Harold B.
Partner: UNT Libraries Government Documents Department

Aerodynamic Factors Affecting the Ability of a Pilot to Return an Airplane to Level From a Banked Attitude by Use of the Rudder Alone and Without Change of Heading

Description: Report presenting a study of the aerodynamic factors upon which the ability to perform the maneuver depends in an attempt to obtain a better understanding of the conditions involved and, if possible, to evolve criterions that may be used during design.
Date: October 1941
Creator: Harmon, S. M.
Partner: UNT Libraries Government Documents Department

Development of Cowling for Long-Nose Air-Cooled Engine in the NACA Full-Scale Wind Tunnel

Description: An investigation of cowlings for long-nose radial engines was made on the Curtiss XP-42 fighter in the NACA full-scale wind tunnel. The unsatisfactory aerodynamic characteristics of all the cowlings with scoop inlets tested led to the development of the annular high-velocity inlet cowlings. Tests showed that ratio of cooling-air velocity at cowling inlet to stream velocity should not be less than 0.5 for this type of cowling and that critical compressibility speed can be extended to more than 500 mph at 20,000 ft altitude.
Date: October 1, 1941
Creator: Guryansky, Eugene R. & Silverstein, Abe
Partner: UNT Libraries Government Documents Department

Investigation of air flow in right-angle elbows in a rectangular duct

Description: Report presenting testing on elbow shapes in airplane carburetor air intake ducts with low losses and good velocity distribution without the use of turning vanes. Results regarding the flow coefficient, velocity distribution, and comparison of a variety of elbow ducts are provided.
Date: October 1941
Creator: McLellan, Charles H. & Bartlett, Walter A., Jr.
Partner: UNT Libraries Government Documents Department

The Selection of Propellers for High Thrust at Low Airspeed

Description: Problem of improving thrust at low speeds is primarily one of reducing angle of attack of operation of sections to improve L/D or reducing blade helix angle. An analysis, based on recent propeller data, is presented for determining improvements in thrust or efficiency which could be obtained by increased number of blades, increased blade width, increased diameter, dual rotation, and two-speed gearing. All methods were found very effective, particularly two-speed gearing.
Date: October 1941
Creator: Biermann, David & Conway, Robert N.
Partner: UNT Libraries Government Documents Department

A study of the effects of vertical tail area and dihedral on the lateral maneuverability of an airplane

Description: Report presenting a theoretical investigation of the influence of changes in vertical tail area and dihedral angle on the lateral flying characteristics of an airplane. Lateral motions were computed for nine different combinations of vertical tail area and dihedral. Results regarding the lateral motions due to applied rolling moment with different amounts of accompanying pawing moment and lateral motions due to applied yawing moment are provided.
Date: October 1941
Creator: Fehlner, Leo F.
Partner: UNT Libraries Government Documents Department

Effect of Humidity on Several Supercharger Parameters

Description: Report presenting testing to determine if the change of several specific variables with extreme change of humidity and test-bench temperature will have an appreciable effect on several parameters used to determine supercharger performance.
Date: November 1941
Creator: Ellerbrock, Herman H., Jr. & Goldstein, Arthur W.
Partner: UNT Libraries Government Documents Department

Flight Measurements of the Elevator Deflections Used in Landings of Several Airplanes

Description: "A collection of data on the elevator deflections used in landings of several airplanes is presented in tabular form. The physical characteristics of these airplanes are also given. The elevator deflections used in landing some airplanes was found to be as much as 14.4 degrees greater than that used to stall under the same flight and loading conditions" (p. 1).
Date: November 1941
Creator: Vensel, Joseph R.
Partner: UNT Libraries Government Documents Department

Investigation of performance of 9-cylinder engine using large valve overlap and eclipse fuel-injection system

Description: Report presenting single-cylinder tests were made with several different engines over a period of time, which have shown that a large overlap between the time of inlet valve opening and exhaust valve closing results in a considerable increase in the maximum power obtainable from a supercharged engine and reduces cylinder temperatures.
Date: November 1941
Creator: Young, Alfred W.
Partner: UNT Libraries Government Documents Department

Wind-Tunnel Investigation of Perforated Split Flaps for Use as Dive Brakes on a Tapered NACA 23012 Airfoil

Description: Aerodynamic characteristics of a tapered NACA 23012 airfoil with single and double perforated split flaps have been determined in the NACA 7- by 10-foot wind tunnel. Dynamic pressure surveys were made behind the airfoil at the approximate location of the tail in order to determine the extent and location of the wake for several of the flap arrangements. In addition, computations have been made of an application of perforated double split flaps for use as fighter brakes. The results indicated that single or double perforated split flaps may be used to obtain satisfactory dive control without undue buffeting effects and that single or double perforated split flaps may also be used as fighter brakes. The perforated split flaps had approximately the same effects on the aerodynamic and wake characteristics of the tapered airfoil as on a comparable rectangular airfoil.
Date: November 1941
Creator: Purser, Paul E. & Turner, Thomas R.
Partner: UNT Libraries Government Documents Department

Wind-Tunnel Tests of Eight-Blade Single and Dual-Rotating Propellers in the Tractor Position

Description: Tests of 10-ft. diameter, eight-blade, single - and dual - rotating propellers were conducted in 20-ft propeller research tunnel. Propellers were mounted at front end of a streamline body in spinners that covered hubs and parts of shanks. Effect of a symmetrical wing mounted in slipstream was investigated. Blade-angle settings ranged from 20 Degrees to 65 Degrees. Results indicated that dual rotation resulted in gains of from 1 to 8 percent in efficiency over single rotation for eight-blade propellers, but presence of a wing reduced gain about one-half. Greater power absorption caused by dual rotation over flight range and higher efficiency or thrust for range of take-off and climb was indicated.
Date: November 1941
Creator: Biermann, David & Gray, W. H.
Partner: UNT Libraries Government Documents Department