A non-destructive procedure enabling one to predict the flutter instability boundary from the data acquired in the subcritical flight speed regime is presented. The proposed technique combines an analytical approach with the experimental tests carried out in flight or in a wind tunnel. The expected outcomes of this study are: a) to reduce the risks of flying in the proximity of the flutter critical boundary, and b) to reduce significantly the amount of flight tests required in any flight clearance test program, that are both time consuming and costly.
Flutter Prediction Using Combined Analytical-Experimental Procedure
INTRODUCTIVE CONSIDERATIONSOne of the most important phases involving the aeroelastic design is the evaluation of the flutter instability boundary by means of flight and tunnel tests at subcritical speed [1,2]. The objective of the flutter analysis is to quantify the critical boundaries of flutter [3][4][5]. Even at the present time, when analytical predictive methodologies have become increasingly useful toward this goal, flight and wind tunnel testing in conjunction with data analysis are always required for the verification of the theoretical predictions. Attempts to formulate adequate methods that permit a reliable prediction of the flutter boundary at speeds well below the flutter speed were made in the past by several investigators [3,[6][7][8] and recently by Lind [5]. As it was pointed out, in order to reduce the number of flight or wind tunnel tests, a reliable technique for real-time monitoring of the aeroelastic stability of the aircraft is required [9]. A systematic approach should 609