Correction of Temperatures of Air-Cooled Engine Cylinders for Variation in Engine and Cooling Conditions (open access)

Correction of Temperatures of Air-Cooled Engine Cylinders for Variation in Engine and Cooling Conditions

"Factors are obtained from semiempirical equations for correcting engine-cylinder temperatures for variation in important engine and cooling conditions. The variation of engine temperatures with atmospheric temperature is treated in detail, and correction factors are obtained for various flight and test conditions, such as climb at constant indicated air speed, level flight, ground running, take-off, constant speed of cooling air, and constant mass flow of cooling air. Seven conventional air-cooled engine cylinders enclosed in jackets and cooled by a blower were tested to determine the effect of cooling-air temperature and carburetor-air temperature on cylinder temperatures" (p. 49).
Date: June 20, 1938
Creator: Schey, Oscar W.; Pinkel, Benjamin & Ellerbrock, Herman H., Jr.
System: The UNT Digital Library
Downwash and Wake Behind Plain and Flapped Airfoils (open access)

Downwash and Wake Behind Plain and Flapped Airfoils

"Extensive experimental measurements have been made of the downwash angles and the wake characteristics behind airfoils with and without flaps and the data have been analyzed and correlated with the theory. A detailed study was made of the errors involved in applying lifting-line theory, such as the effects of a finite wing chord, the rolling-up of the trailing vortex sheet, and the wake. The downwash angles, as computed from the theoretical span load distribution by means of the Biot-Savart equation, were found to be in satisfactory agreement with the experimental results" (p. 179).
Date: June 23, 1938
Creator: Silverstein, Abe; Katzoff, S. & Bullivant, W. Kenneth
System: The UNT Digital Library
The influence of lateral stability on disturbed motions of an airplane with special reference to the motions produced by gusts (open access)

The influence of lateral stability on disturbed motions of an airplane with special reference to the motions produced by gusts

"Distributed lateral motions have been calculated for a hypothetical small airplane with various modifications of fin area and dihedral setting. Special combinations of disturbing factors to simulate gusts are considered and the influence of lateral stability on the motions is discussed. Fin area and wing dihedral were found to be of primary importance in side gusts. It was found that the rolling action of the wing with as much as 5 degrees dihedral was distinctly unfavorable, especially when the weathercock stability was small. It is pointed out that the greatest susceptibility to lateral disturbances lies in the inherent damping and coupling moments developed by the wing" (p. 507).
Date: June 8, 1938
Creator: Jones, Robert T.
System: The UNT Digital Library
Investigation in the 7-by-10 Foot Wind Tunnel of Ducts for Cooling Radiators within an Airplane Wing (open access)

Investigation in the 7-by-10 Foot Wind Tunnel of Ducts for Cooling Radiators within an Airplane Wing

Report presents the results of an investigation made in the NACA 7 by 10-foot wind tunnel of a large-chord wing model with a duct to house a simulated radiator suitable for a liquid-cooled engine. The duct was expanded to reduce the radiator losses, and the installation of the duct and radiator was made entirely within the wing to reduce form and interference drag. The tests were made using a two-dimensional-flow setup with a full-span duct and radiator. Section aerodynamic characteristics of the basic airfoil are given and also curves showing the characteristics of the various duct-radiator combinations.
Date: June 9, 1938
Creator: Harris, Thomas A. & Recant, Isidore G.
System: The UNT Digital Library