Results of a Fifteen-Year Program of Flexural Fatigue Testing of Gear Teeth

This is a report of a continuing program of testing gear teeth which had its inception in 1946. In the course of the program about 3000 gear teeth have been broken under controlled laboratory conditions. The results of tests have been incorporated into gear design work in many fields. Gears now in use by the U. S. Navy are designed for intensities of tooth loading about double that of World War II. In the aircraft field the typical propeller drive gear carries about twice the intensity of loading as in World War II. Gears of almost fantastic intensities of loading are in use in rocket engines.