High Temperature Advanced Composite Drive Shafts

Filament wound advanced composite drive shafts provide critical performance at reduced weight for several engine to gearbox connections in the V-22 aircraft system. Recent events have shown that these components may be required to withstand direct flame exposure without loss of structural integrity. Typical epoxy matrix materials will degrade and fail under these conditions. Even metal drive shafts can warp and deform when directly exposed to flame. Simply replacing the epoxy matrix with a "high temperature" resin such as BMI or polyimide, does not solve the fire problem. Additionally, these materials raise issues regarding costs processability, and damage tolerance. Foster-Miller, together with team members Bell Helicopter Textron and BP Chemicals, proposes to develop a low cost, lightweight advanced composite drive shaft to function under normal operating conditions while providing for continued operation in the event of fire. To accomplish this we will combine standard drive shaft design congiguration with one of three fire protection schemes which are described in the body of this proposal. Each of these concepts have been proven effective for different applications where fire protection is critical, and offer considerable potential for enhancing fire performance while requiring minimum modifications to the basic drive shaft design.