Full Scale Fatigue Testing of the F/A-18 Empennage

ARL is preparing for a full-scale fatigue test of the F/A-18 aft fuselage and empennage in collaboration with Canada who will test the centre fuselage and wings. These tests will provide durability and damage tolerance data for the RAAF and Canadian Forces (CF) to enable economic and safe management of their F/A-18 fleets. Extensive fatigue testing has been conducted by the F/A-18 manufacturers but the load spectra have not been representative of RAAF usage and the test loading methods have not fully represented the flight conditions. At high angles of attack the F/A-18 tail surfaces are subject to severe buffeting and undergo severe vibrations in addition to manoeuvre loading. ARL has developed a technique using airsprings and hydraulic shakers to apply combined manoeuvre and dynamic loads in the test. The proposed loading system is described in the paper.