Abstract:
The AW609 tiltrotor is the first new class of air vehicle pursuing civil certification in over fifty years under FAA order 21.17B. The primary safety objective for crashworthiness for any aviation vehicle is to maximize the probability of survival and to minimize the probability of post-crash fires. A unique feature of the AW609 design is a high mounted wing above the fuselage, with nacelles at the end of the wing that contain heavy items of mass such as engines, rotor systems and transmissions. In order to create a viable aviation product with suitable empty weight fraction a controlled wing failure mechanism at the wing root is included to shed wing and nacelle mass in high g landing events. This allows for protection of the fuselage and the occupants up to the full regulatory vertical landing requirement of 12 g's. An analysis supported by test methodology is presented that includes explicit dynamic finite element modeling, coupon, element and full-scale drop testing of a full span AW609 wing. The objective of the testing is to characterize the equivalent quasi-static g level for damage initiation and progressive damage progression for the tested configuration, and to validate the associated analysis. The dynamic analysis, once validated by test, shall be used to analyze other weight and center of gravity combinations relevant to the anticipated AW609 mission profiles.