Development of helicopter safety devices

Recent investigations indicate that improvement of helicopter occupant safety can be obtained by the optimisation of energy absorbing seat properties, specifically the introduction of variable load/stroke attenuators and the reduction of overall seat stroke length. This paper reviews these devices and investigates the feasibility of forward sliding seats and airbags in the helicopter environment. Results indicate that seat attenuators vastly reduce occupant lumbar loads in crash scenarios. Moreover, analysis has shown that the introduction of forward sliding seats coupled with seat attenuators improved occupant safety by translating crash loads to the forward axis, reducing vertical loads. Finally, the introduction of airbags was found to increase the available space for stroking devices, improving energy absorption of the safety system and acted to reduce the potential for hard contact between the occupant and instrument panel.