[31] A 2-stroke cycle engine completes 360° of crankshaft rotation in what it takes a 4-stroke cycle engine 720° to accomplish. A 3-cylinder two-stroke cycle engine therefore has the same capacity to do work as a 6-cylinder four-stroke cycle engine. For this reason the former type of engine is both more compact and lighter than the latter type.
The above advantages, plus the increased efficiency of the blown 2-cycle diesel, are discussed in Flight—The Aeronautical Engineer Supplement (December 26, 1940), vol. 19, no. 11, pp. 545 and 552.
[32] Packard advertisement—Aero Digest (June 1930), vol. 16, no. 6, p. 23.
[33] Aviation (March 15, 1930), vol. 28, no. 11, p. 531.
[34] The National Aeronautic Magazine (April 1932), vol. 10, no. 4., p. 18.
[36] See Woolson’s patent 1794047, issued in 1931 and assigned to the Packard Motor Car Company. “An object of my invention is to automatically regulate the compression ratio in an engine inversely to the speed....” See also his patent 1891321, issued in 1932 and assigned to the Packard Motor Car Company. It describes a similar but nonautomatic system. Woolson therefore fully realized the disadvantages of the high cylinder pressures his engine developed at high rpm’s.
[37] Letter, Clarence H. Wiegman to National Air Museum, November 1, 1961.
[38] Ibid.
[39] Major George E. A. Hallet, U.S. Air Service, former director of engineering division, McCook Field, Dayton, Ohio.