Some characteristics of fuel sprays at low-injection pressures (open access)

Some characteristics of fuel sprays at low-injection pressures

"This report presents the results of tests conducted at the Langley Memorial Aeronautical Laboratory, Langley Field, Va., to determine some of the characteristics of the fuel sprays obtained from an 0.008-inch and a 0.020-inch open nozzle when injection pressures from 100 to 500 pounds per square inch were used. Fuel oil and gasoline were injected into air at densities of atmospheric land 0.325 pound per cubic foot. It was found that the penetration rate at these low pressures was about the same as the rate obtained with higher pressures. Spray cone-angles were small and individual oil drops were visible in all the sprays. Gasoline and fuel oil sprays had similar characteristics" (p. 1).
Date: November 1931
Creator: Rothrock, A. M. & Waldron, C. D.
System: The UNT Digital Library
Advantages of Oxide Films as Bases for Aluminum Pigmented Surface Coatings for Aluminum Alloys (open access)

Advantages of Oxide Films as Bases for Aluminum Pigmented Surface Coatings for Aluminum Alloys

Report discussing both laboratory and weather-exposure corrosion tests showed conclusively that the protection afforded by aluminum pigmented spar varnish coatings applied to previously anodized aluminum surfaces was greatly superior to that afforded by the same coatings applied to surfaces which had simply been cleaned free from grease and not anodized.
Date: November 1931
Creator: Buzzard, R. W. & Mutchler, W. H.
System: The UNT Digital Library
The effect of slots and flaps on the lift and drag of the McDonnell Airplanes determined in flight (open access)

The effect of slots and flaps on the lift and drag of the McDonnell Airplanes determined in flight

This note contains the results of flight test conducted by the National Advisory Committee for Aeronautics on a low-wing monoplane equipped with leading-edge slots extending over the entire wing and flaps extending only to the ailerons, to find their effect on the lift and drag characteristics of the airplane. Curves are given showing the lift and drag characteristics of the airplane for the following conditions of the slots and flaps neutral; slots closed and flaps down; and slots open and flaps down. In addition, the high and low speed in level flight and the climbing characteristics are given. The results show that the slots used alone increase the maximum lift coefficient 54 per cent; the flaps alone increase it 38 per cent; and the slots and flaps in combination decrease the landing speed from 60 to 43 m.p.h.; increase the speed range of the airplane 40 per cent; and increase the glide angle at landing speed 4.2 degrees.
Date: November 1931
Creator: Soulé, Hartley A.
System: The UNT Digital Library
The aerodynamic characteristics of six commonly used Airfoils over a large range of positive and negative angles of attack (open access)

The aerodynamic characteristics of six commonly used Airfoils over a large range of positive and negative angles of attack

From Summary: "This paper presents the results of tests of six commonly used airfoils: the CYH, the N-22, the C-72, the Boeing 106, and the Gottingen 398. The lifts, drags, and pitching moments of the airfoils were measured through a large range of positive and negative angles of attack. The tests were made in the variable density wind tunnel of the National Advisory Committee for Aeronautics at a large Boeing 106, and the Gottingen 398 airfoils, the negative maximum lift coefficients were found to be approximately half the positive; but for the M-6 and the CYH, which have less effective values were, respectively, 0.8 and 0.6 of the positive values."
Date: November 1931
Creator: Anderson, Raymond F.
System: The UNT Digital Library