UNT Libraries Government Documents Department - 260 Matching Results

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Activation of hydrocarbons and the octane number

Description: This report presents an examination of the history of research on engine knocking and the various types of fuels used in the investigations of this phenomenon. According to this report, the spontaneous ignition of hydrocarbons doped with oxygen follows the logarithmic law within a certain temperature range, but not above 920 degrees K. Having extended the scope of investigations to prove hydrocarbons, the curves of the mixtures burned by air should then be established by progressive replacement… more
Date: October 1939
Creator: Peschard, Marcel
Item Type: Refine your search to only Report
open access

Adhesion of Ice in Its Relation to the De-Icing of Airplanes

Description: From Summary: "The various possible means of preventing ice adhesion on airplane surfaces are critically reviewed. Results are presented of tests of the adhesives forces between ice and various solid and liquid forces. It is concluded that the de-icing of airplane wings by heat from engine exhaust shows sufficient promise to warrant full-scale tests. For propellers, at least, and possibly for certain small areas such as windshields, radio masts, etc. the use of de-icing or adhesion-preventing l… more
Date: August 1939
Creator: Rothrick, A. M. & Selden, R. F.
Item Type: Refine your search to only Report
open access

Aerodynamic Characteristics of a 4-Engine Monoplane Showing Comparison of Air-Cooled and Liquid-Cooled Engine Installations

Description: From Introduction: "An investigation has been conducted in the N.A.C.A. full-scale wind tunnel to determine the aerodynamic characteristics of a 1/4-scale model of a 4-engine monoplane when equipped with comparable air-cooled engine and liquid-cooled engine installations. The air-cooled engine installation consisted of nacelles equipped with N..A.C.A. cowlings and oil coolers located in the leading edge of the wing."
Date: July 1939
Creator: Silverstein, Abe & Wilson, Herbert A., Jr.
Item Type: Refine your search to only Report
open access

The aerodynamic characteristics of six full-scale propellers having different airfoil sections

Description: From Summary: "Wind-tunnel tests are reported of six 3-blade 10-foot propellers operated in front of a liquid-cooled engine nacelle. The propellers were identical except for blade airfoil sections, which were: Clark y, R.A.F. 6, NACA 4400, NACA 2400-34, NACA 2rsub200, and NACA 6400. The range of blade angles investigated extended for 15 degrees to 40 degrees for all propellers except the Clark y, for which it extended to 45 degrees. The results showed that the range in maximum efficiency betwee… more
Date: 1939
Creator: Biermann, David & Hartman, Edwin P.
Item Type: Refine your search to only Report
open access

Aircraft rate-of-climb indicators

Description: From Summary: "The theory of the rate-of-climb indicator is developed in a form adapted for application to the instrument in its present-day form. Certain dynamic effects, including instrument lag, and the use of the rate-of-climb indicator as a statoscope are also considered. Modern instruments are described. A laboratory test procedure is outlined and test results are given."
Date: 1939
Creator: Johnson, Daniel P.
Item Type: Refine your search to only Report
open access

Airfoil section characteristics as affected by variations of the Reynolds number

Description: Report presents the results of an investigation of a systematically chosen representative group of related airfoils conducted in the NACA variable-density wind tunnel over a wide range of Reynolds number extending well into the flight range. The tests were made to provide information from which the variations of airfoil section characteristics with changes in the Reynolds number could be inferred and methods of allowing for these variations in practice could be determined. This work is one phas… more
Date: 1939
Creator: Jacobs, Eastman N. & Sherman, Albert
Item Type: Refine your search to only Report
open access

Airfoil Theory at Supersonic Speed

Description: From Summary: "A theory is developed for the airfoil of finite span at supersonic speed analogous to the Prandtl airfoil theory of 1918-1919 for incompressible flow. In addition to the profile and induced drags, account must be taken at supersonic flow of still another drag, namely, the wave drag, which is independent of the wing aspect ratio. Both wave and induced drags are proportional to the square of the lift and depend on the Mach number, that is, the ratio of flight to sound speed. In gen… more
Date: June 1939
Creator: Schlichting, H.
Item Type: Refine your search to only Report
open access

Apple scab.

Description: Discusses apple scab, its economic impact, distribution, susceptibility of various apples to the disease, and preventive measures.
Date: 1939
Creator: Roberts, John W. (John William), 1882-1957. & Pierce, Leslie.
Item Type: Refine your search to only Book
open access

An approximate spin design criterion for monoplanes

Description: "A quantitative criterion of merit has been needed to assist airplane designers to incorporate satisfactory spinning characteristics into new designs. An approximate empirical criterion, based on the projected side area and the mass distribution of the airplane, has been formulated in a recent British report. In the present paper, the British results have been analyzed and applied to American designs. A simpler design criterion based solely on the type and the dimensions of the tail, has been d… more
Date: June 1939
Creator: Seidman, Oscar & Donlan, Charles J.
Item Type: Refine your search to only Report
open access

Bean Bacterial Wilt.

Description: Describes the signs that beans are infected with bacterial wilt, the history of the disease, where it most often occurs, and the steps that can be taken to control it.
Date: February 1939
Creator: Hedges, Florence
Item Type: Refine your search to only Book
open access

The Breda Wind Tunnel

Description: A description of the design and construction of the Breda wind tunnel. The tunnel is equipped with a two-meter throat diameter and a 310 kph velocity potential.
Date: December 1939
Creator: Pittoni, Mario
Item Type: Refine your search to only Report
open access

The Calculated Effect of Various Hydrodynamic and Aerodynamic Factors on the Take-Off of a Large Flying Boat

Description: Present designs for large flying boats are characterized by high wing loading, high aspect ratio, and low parasite drag. The high wing loading results in the universal use of flaps for reducing the takeoff and landing speeds. These factors have an effect on takeoff performance and influence to a certain extent the design of the hull. An investigation was made of the influence of various factors and design parameters on the takeoff performance of a hypothetical large flying boat by means of take… more
Date: June 1939
Creator: Olson, R. E. & Allison, J. M.
Item Type: Refine your search to only Report
open access

Calculation of the Aerodynamic Characteristics of Tapered Wings With Partial-Span Flaps

Description: "Factors derived from wing theory are presented. By means of these factors, the angle of zero lift, the lift-curve slope, the pitching moment, the aerodynamic-center position, and the induced drag of tapered wings with partial-span flaps may be calculated. The factors are given for wings of aspect ratios 6 and 10 , of taper ratios from 0.25 to 1.00, and with flaps of various length. An example is presented of the method of application of the factors. Fair agreement with experimental results is … more
Date: January 23, 1939
Creator: Pearson, Henry A. & Anderson, Raymond F.
Item Type: Refine your search to only Report
open access

Calculation of the Induced Efficiency of Heavily Loaded Propellers Having Infinite Number of Blades

Description: Report presenting an approximate method of computing the induced efficiency of heavily loaded propellers in suitable form for extension to finite number of blades and a comparison of results obtained using the method with the data of the Betz-Helmbold theory for heavily loaded propellers.
Date: January 1939
Creator: Lösch, F.; Kramer, K. N.; Bock, G. & Nikodemus, R.
Item Type: Refine your search to only Report
open access

The charging process in a high-speed, single-cylinder, four-stroke engine

Description: From Summary: "Experimental measurements and theoretical calculations were made on an aircraft-type, single cylinder engine, in order to determine the physical nature of the inlet process, especially at high piston speeds. The engine was run at speeds from 1,500 to 2,600 r.p.m. (mean piston speeds of 1,370 to 2,380 feet per minute). Measurements were made of the cylinder pressure during the inlet stroke and of the power output and volumetric efficiency. Measurements were also made, with the eng… more
Date: February 1939
Creator: Reynolds, Blake; Schecter, Harry & Taylor, E. S.
Item Type: Refine your search to only Report
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