F-111 Adhesively Bonded Repair Assessment Program (FABRAP) - Phase 1 Testing, Preliminary Results

Abstract : Adhesive bonded repairs are being used for the through-life-support of secondary and tertiary aircraft structure. This technology has not been accepted for application to primary aircraft structure due largely to the lack of a non-destructive inspection technique for, and uncertainty regarding the environmental durability of, adhesive bonds. Over the last twenty five years a large number of adhesive bonded repairs have been applied to the Royal Australian Air Force F-111 and its retirement in December 2010 represented a unique opportunity to evaluate the bonded repairs. The F-111 Adhesive Bonded Repair Assessment Program (FABRAP) was created to generate statistically valid data regarding the efficacy of the tap-test as a non-destructive-inspection technique and the environmental durability of adhesive bonds. In FABRAP Phase I Testing, over 300 repairs were tap tested and 820 residual strength tests conducted using a pneumatic adhesion tensile testing instrument. This report details the FABRAP process and summarises the results from the Phase I testing.