Flutter TestsTesting of the flexibility of the plane’s structure

Flutter analysis - ground vibration test (EASA type certification Viper SD4)

Part of the certification process  - EASA type certification of Viper SD4, is also execution of ground vibration test. The result of vibration tests is, at a design speed of the aircraft Viper SD4 there is not exist a dangerous phenomenon - vibration of aircraft control surfaces (Flutter). In connection with the execution of ground vibration tests we realized also oscillation of the aircraft through adding of the vibrations into the aircraft. Vibrations oscillated the Viper SD4 and the aircraft made the sound.
 

Video - EASA ground vibration test

 

Photo documentation of testing the strength and flexibility of the structure of the aeroplane and of its main parts

 
Specialists from the Department of Airspace Engineering of the Faculty of Mechanical Engineering of ČVUT (Czech University of Technology) in Prague carried out tests of the flexibility of the plane’s structure and of all its parts, so-called flutter tests. The basis of the test is in the analysis of the combined effect of aerodynamic, elastic and mass forces in the airplane’s structure. We carried out the measurement of amplitudes and responses in the transmission of vibration waves into the fuselage and wings of the plane. The tests verified the aeroelastic properties of the plane and of its structure and allowed to assess the risk of flutter throughout the plane’s operational airspeeds.
 
The carried out flutter tests have shown the resistance of all structural parts of Viper SD4 to flutter under the given distribution of aerodynamic forces. Viper SD4 completed that demanding test by flight tests - and thus proved its resistance to flutter.