Application of Superplastic Forming/Diffusion Bonding (SPF/DB) of Titanium Structure (T-38 Main Landing Gear Strut Door).

Abstract : This final report presents the results of a program to design, develop, fabricate and flight qualification test a Superplastic Formed/Diffusion Bonded (SPF/DB) 6Al-4V Titanium sandwich T-38 Main Landing Gear (MLG) Strut Door. Because of the high incidence of corrosion ans susceptibility to FOD, the T-38 MLG Strut Door was chosen as an ideal component to demonstrate the Operations Spares (O&S) cost and/or Life Cycle Cost (LCC) savings achievable with SPF/DB technology. Required to be of equivalent Form, fit, and function, 6 full scale trusscore configuration titanium sandwich doors were designed (Finite Element Modeling) on 22-4-9 steel production type tooling. The SPF/DB door in flight qualified configuration was measured to be 0.7 lbs. lighter than the baseline aluminum H/C door. A fleet life cycle cost savings for right and left hand doors of $32.6M was projected. Full-scale flight qualification static testing was conducted and subsequent to the technical period of performance, successful flight service evaluation was conducted by the Air Force Logistics Command at Kelly AFB, San Antonio, Texas. (Author)