Helicopter Elastomeric Drive Shaft Mount Design Synthesis and Performance Analysis

To increase the operational readiness, minimize the maintenance cost, and reduce the vibration-induced structural loads on the tail boom of the helicopter, Lord Corporation has developed a series of tail rotor elastomeric drive shaft mounts for both Sikorsky medium-lift S-92 and heavy-lift CH-53E. Lord’s elastomeric drive shaft mounts are designed to isolate the high-speed rotating drive shaft from the fuselage, to limit motions during helicopter run-up and transient maneuvers, and to allow the drive shaft to rotate after seizure of the bearing, giving the helicopter time to make an emergency landing. A tail rotor drive shaft mount design synthesis is described. Lord Corporation’s proprietary DYNAMOUNT program, which is the primary tool used in the drive shaft mount process, is also presented along with results from the S-92 and CH-53E designs.