Static response of a composite wing under a whiffletree loading

This paper presents the results of an investigation focused on the static response of a full-scale carbon composite wing assembly of an ultralight UAV. The aircraft has a 36-ft wingspan and a design gross weight of 450-lb (empty weight = 155-lb). A threetier whiffletree system is designed and used to simulate a distributed load on the wing with force intensity and resultant that are consistent with a high-g flight condition. With the help of multiple strain and deflection gages, the static response of the wing is measured at various spanwise and chordwise locations with incremental loading ranging from zero over the limit and design ultimate loads to the point of structural failure. A geometric and material nonlinear finite element model is developed to predict the static response of the wing up to the design ultimate load. Preliminary simulation results match reasonably well with the measured data. The lightweight composite wing is found to be very stiff and strong with the average failure load corresponding to 6.7-g's. The load response and failure characteristics of the wing are also presented and discussed.

American Society for Composites - 22nd Technical Conference of the American Society for Composites 2007 - Composites: Enabling a New Era in Civil Aviation

Static response of a composite wing under a whiffletree loading Conference Paper