Flutter/ASE Flight Test Risk Control Technique of Civil Fly-by-wire Aircraft

Abstract

The existing research on flight test risk control techniques related to flutter/ASE test is not systematic enough,and has limited consideration of civil fly-by-wire aircraft characteristic and onboard flight test engineer.The flutter/ASE flight test risk control technique is systematically studied,which includes the theoretical evaluation,test modification,flight test method,flight test risk analysis,risk mitigation measures and emergency procedures formulation. Aiming at three identified hazards including flutter/ASE instability,adverse handling quality and local structure damage,a new technique is proposed for onboard flight test engineers to cutoff the excitation when the vibration limit is exceeded or abnormal. The dedicated ground monitor software is developed to perform the margin quantitative analysis of flutter/ASE in real time. The technique is applied to a certain model flight test for flutter/ASE flight test verification. The results show that the risk control technique can reduce the flight test risk and cost effectively,the manual cutoff technique can stop the excitation within 1 second to protect the aircraft structure safety,and the real-time analysis technique can calculate the stability margin quickly and improve the flight test efficiency.

Keywords

• flutter/ase flight test
• frequency sweep
• risk evaluation
• manual cutoff
• real-time analysis