The oil-off performance evaluation of gears is of significant interest to the Department of Defense and various rotorcraft manufacturers, so that the aircraft can safely land in an accidental loss-of-lubricant situation. However, unlike typical gear failure modes, gear failure in an oil-off situation is very rapid and likely catastrophic. This paper describes the procedure and instrumentation utilized for an oil-off test to measure the frictional loss in the test gear mesh and the “air” temperature just out of mesh. Sound and vibration data was also recorded during testing. Data from typical failures showing the detection of scuffing onset and its progression to catastrophic failure for gears made from several aerospace alloy steels is presented.

ISBN: 978-1-64353-011-6
Pages: 17
Authors: Aaron C. Isaacson and Matthew E. Wagner