NASA researchers recently conducted drop tests of a Boeing Vertol CH-46 Sea Knight to test improved seats and seat belts. They recorded the crash from more than 350 data channels as the helicopter, suspended by cables, was dropped into a bed of soil from 30 feet up. Just before impact, pyrotechnic devices released the suspension cables from the helicopter to allow free flight toward impact with a forward speed of approximately 30 mph.
Technicians painted one entire side of the helicopter in black polka dots over a white background, each dot representing a data point. High-speed cameras filming at 500 images per second tracked each dot, so researchers could plot exactly how the fuselage buckled, bent, cracked or collapsed under crash loads.
The impact conditions represented a severe but survivable condition under both civilian and military requirements.
Another helicopter drop test with more sensors is planned for next year.