Experimental Investigation of the Effect of Flap Angle and Weight on Flutter of an Aircraft by Using Flight Test

In this research، the operational plan are prepared based on the standard requirement of flutter test for an aircraft. Therefore the analytic recognition algorithms of excitation frequency and damping estimations from response data is surveyed in different flight condition. The resultants is presented in condition of mid height and field elevation (FM); 5600 feet with usage of zero، 10 and 38 degrees flap angles. In this research the parametric data gathering to be considered with covering the Performance curves limitation. The purpose of the present work، was access to flutter airspeeds with application ability in type certification program (TC) and flight manual completion (FM) for a jet trainer. The results indicate that by increasing the angle of flap in critical limitations of flight envelope attention to leap of the dynamic frequency response due to structure excitation to infinite and entry to less rate of structural damping، flutter phenomenon occur in lower airspeed. Whereas by change in weight configurations from light to heavy in same flap angle، this decreased rate in flutter airspeed don''t observe significantly. in this article is imparted both method of flutter airspeed estimation in form of response-frequency diagrams and damping-airspeed in parallel and adaptively