AT SEVERAL TWIN- AND SINGLE-ENGINE OPERATING CONDITIONS AT VARIOUS ALTITUDES

WASHINGTON NACA WARTIME REPORTS are reprints of papers originally Issued to provide rapid distribution of advance research results to an authorized group requiring them for the war effort. They were pre-viously held under a security status but are now unclassified. Some of these reports were not tech-nically edited. All have been reproduced without change in order to expedite general distribution