Abstract:

Landing gear is one of the key components of armed helicopters during their design. The dynamic behavior of the landing gear, especially its energy absorbing capability, plays an important role in attenuating the impulsive loading and ensuring the survivability of occupants. This paper firstly introduces the basic design principles of helicopter crashworthiness, and then a typical example of a landing gear associated with a fuselage represented by an effective mass system of the rigid truss undergoing the hard landing impact vertically to the ground with a velocity of 6m/s is studied by using two approaches. One is FEM analysis based on the dynamic model and the other is energy absorbing by the landing gear during the hard landing (crash) process; the change of the kinetic energy of the helicopter and the impact curve of the main attenuation oleo cylinder have been given. Furthermore, a comparison between the results obtained from the two approaches is made. The study can be used as a theoretical instruction for the new type of helicopter crashworthiness design.

Key words: crashworthiness, helicopter, landing gear, FEM, dynamics