Research in Engineering and Aviation

Reduction of Vertical Tail Buffet Response Using Active Control

May/June 1996

Author(s): Hauch, R.M., Jacobs, J.H., Dima, C., and Ravindra, K.

Journal: Journal of Aircraft, Vol. 33, No. 3, May-June 1996.


The active vertical tail (AVT) successhlly reduced the buffet response of structures by utilizing piezoelectric actuators, strain gauge sensors, and simple control techniques. The AVT is a 5%-scale aeroelastically tailored structure that exhibits vibration response similar to a full-scale aircraft structure, and was designed such that it’s piezoelectric actuators could provide control authority in the first two bending modes. The AVT was wind-tunnel tested on a generic twin-tailed double-delta fighter model at angles of attack and dynamic pressures representative of actual aircraft flight envelopes. At high angles of attack, the model’s leading-edge vortices impinge upon the AVT. Simple control algorithms were used with piezoelectric actuators and collocated strain gauge sensors to either minimize the acceleration at the AVT’s tip or the strain at the root of the tail. Control gains were verified to be a nonlinear function of angle of attack, dynamic pressure, and location of the actuatorlsensor pair. Spectral analysis showed that the peak response of the controlled AVT was up to 65% lower than the uncontrolled response. This represents approximately an order of magnitude improvement in the fatigue life of a similar aircraft structure. The rms response below 200 Wz was reduced by over 20%.