The feasibility of using trailing-edge aps to recon gure a helicopter rotor blade following a failure of the pitch link is addressed, which makes the blade free oating in pitch and otherwise uncontrollable. A coupled rotorfuselage model is developed that allows for rotor anisotropy. A new, optimization-based,trim procedure is developed to determine the dynamics of the failed blade and the ap inputs required for recon guration. The trailing-edge ap can correct the otherwise catastrophic

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... ces of a pitch link failure. The residual 1 and 2/rev (revolution) components of the hub loads are reasonably small with a one-harmonic ap input and essentially disappear if a second harmonic is added to the ap input. The required ap de ections are high but not unreasonable. The ap acts by generating a rigid-body pitching motion of the free-oating blade that matches the angles that otherwise would have been generated by the swashplate. The steady-state apping motion of the recon gured blade is very nearly identical to those of the undamaged blades. The solutions are very sensitive to phase errors in the rst harmonic of the ap inputs. The sensitivity is lower for the constant and the second harmonic inputs. The result suggests that if a helicopter rotor is equipped with trailing-edge aps for other purposes such as vibration or noise reduction, these aps could be used as emergency control surfaces.