Development & Testing of a Rotorcraft Engine Transmission Lubrication System

Within high-speed aerospace transmissions, lubrication system design contributes heavily to windage losses and overall transmission efficiency. Often, qualifying the lubrication system for a high-speed transmission is considered one of the largest risks to a program given the transmission’s predisposition to overheat and the iterative nature of lubrication system design. This paper describes the development of a new high-speed transmission lubrication scavenge system and the testing that was done to qualify two separate configurations of the transmission for flight test. The testing detailed in this paper was successful in qualifying a research and development transmission for the H47 T408 Engine Demonstration Program and was utilized to inform future lubrication system designs for high-speed transmissions.