A Study of Transparent Plastics for use on Aircraft, Special Report (open access)

A Study of Transparent Plastics for use on Aircraft, Special Report

"Various transparent organic plastics, including both commercially available and experimental materials, have been examined to determine their suitability for use as flexible windshields on aircraft, The properties which have been studied include light transmission, haziness, distortion, resistance to weathering, scratch and indentation hardness, impact strength, dimensional stability, resistance to water and various cleaning fluids, bursting strength at normal and low temperatures, and flammability" (p. 1).
Date: May 12, 1937
Creator: Axilrod, Benjamin M. & Kline, Gordon M.
Object Type: Report
System: The UNT Digital Library
Armstrong Whitworth 27 "Ensign" Commercial Airplane (British): An All-Metal High-Wing Monoplane (open access)

Armstrong Whitworth 27 "Ensign" Commercial Airplane (British): An All-Metal High-Wing Monoplane

Circular presenting a description of the Armstrong Whitworth monoplane, which is an all-metal, high-wing monoplane with landing gear that retracts into the wing-mounted engine nacelles. Details of the wings, wing spars, fuselage, controls, engines, speeds, drawings, and photographs are provided.
Date: May 1937
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Discharge characteristics of a double injection-valve single-pump injection system (open access)

Discharge characteristics of a double injection-valve single-pump injection system

The discharge characteristics of two similar injection valves operated by a single-cylinder fuel-injection pump were determined with an apparatus that measured the quantity of fuel discharged from each valve during every 0.5 degrees of pump rotation. It was found that similar discharges took place from the two valves at all pump speeds when the valve-opening pressures, the nozzle-orifice diameters, and the injection-tube lengths were the same for both valves. Under these conditions, the effects of changing the pump speed, the pump throttle setting, or the nozzle orifice diameter were very similar to those occurring with a single-injection valve. By a proper selection of discharge-orifice areas and valve-opening pressures it was possible to obtain a great many combinations of discharge quantities, discharge rates, and injection timings for the two valves. A series of tests using injection tubes of unequal lengths for the two valves showed that under these conditions the injection timing and the fuel quantity discharged from each valve varies widely and erratically with changes in the pump speed.
Date: May 1937
Creator: Lee, Dana W. & Marsh, E. T.
Object Type: Report
System: The UNT Digital Library
Heat transfer from cylinders having closely spaced fins (open access)

Heat transfer from cylinders having closely spaced fins

The heat-transfer coefficients have been determined for five steel cylinders having fins 1.22 inches wide and the spacing between the fins ranging from 0.022 to 0.131 inch. The cylinders were tested with and without baffles in a wind tunnel; they were also tested enclosed in jackets with the cooling air supplied by a blower. A maximum heat transfer was reached at a fin space of about 0.45 inch for the cylinders tested with each of the three methods of cooling investigated. The rise in temperature of the air passing between the fins and the change in flow pattern were found to be important factors limiting the heat transfer that may be obtained by decreasing the fin space. The use of baffles for directing the air around the cylinders with closely spaced fins proved very effective in increasing the over-all heat-transfer coefficient, provided that the spacing was not appreciably less than that for maximum heat transfer.
Date: May 1937
Creator: Biermann, Arnold E.
Object Type: Report
System: The UNT Digital Library
Helicopter Problems (open access)

Helicopter Problems

The present report deals with a number of the main problems requiring solution in the development of helicopters and concerning the lift, flying performance, stability, and drive. A complete solution is given for the stability of the helicopter with rigid blades and control surfaces. With a view to making a direct-lift propeller sufficient without the addition of auxiliary propellers, the "flapping drive" is assessed and its efficiency calculated.
Date: May 1937
Creator: Küssner, H. G.
Object Type: Report
System: The UNT Digital Library
The lateral instability of deep rectangular beams (open access)

The lateral instability of deep rectangular beams

"Experimental and analytical studies were made of solid and hollow deep rectangular beams to study their lateral instability under various conditions of loading and restraint. The tests were made on bars and tubes of 17ST aluminum alloy. Failure by lateral buckling occurred only in tests on the solid beams. It was found that, within the elastic range, the test results were in agreement with the classical theory for the lateral buckling of deep beams as given by Prandtl, Mitchell, and Timoshenko" (p. 1).
Date: May 1937
Creator: Dumont, C. & Hill, H. N.
Object Type: Report
System: The UNT Digital Library
Rammed Earth Walls for Buildings. (open access)

Rammed Earth Walls for Buildings.

Describes how to construct a building that uses rammed earth for walls.
Date: May 1937
Creator: Betts, M. C. (Morris Cotgrave), 1875-1936 & Miller, T. A. H. (Thomas Arrington Huntington), 1885-
Object Type: Book
System: The UNT Digital Library
The Scale Effect in Towing Tests With Airplane-Float Systems (open access)

The Scale Effect in Towing Tests With Airplane-Float Systems

"The present report includes a description of the making of three-component measurements on a full-size float mounted on an actual airplane and the comparison of the results with those from two models of the same form but of different size which had been tested in the towing tank. The purpose of the comparison is to determine the effect of the Reynolds Number on the results of model tank tests. Following a brief discussion of previous tests intended to elucidate the problem of scale effect on float systems and a description of the testing equipment, the choice of the reference quantities to be used in the comparison is discussed" (p. 1).
Date: May 1937
Creator: Schmidt, Rudolph
Object Type: Report
System: The UNT Digital Library
The Source of Propeller Noise (open access)

The Source of Propeller Noise

A two blade propeller of 40 cm diameter and zero pitch was explored for its noise development; it could be whirled up to 17,000 rpm - i.e., a tip speed of 355 meters/second. To obtain the power loss N(sub m) of the propeller for comparison with the produced acoustical power N(sub A) the engine performance characteristics were measured with and without propeller. The result is the sought-for relation c, that is, curve c' after correction with the engine efficiency.
Date: May 1937
Creator: Ernsthausen, W.
Object Type: Report
System: The UNT Digital Library