An unplanned descent in a helicopter is obviously highly dangerous.
Today’s invention offers a way to lessen that danger when flying over water.
The fuselage of the machine contains flotation bags and is shaped in such a way as to minimise the initial impact with the water surface.
The accelerations are thus smoothed out over time, as the knifelike profile penetrates the water, resulting in much less severe injuries to occupants.
This profile could be made thin enough in cross-section that the day-to-day drag would not be greater than that for a normal airframe shape.
Once the machine has submerged and the buoyancy force exceeds the weight, it would return to the surface and remain there until rescued.
Fixed wing aircraft could emulate this approach too, so that when about to crash in the sea, a plane could rotate through 90 degrees (one wing at six and the other at 12 o’clock).