I am not aware of any aircraft ditching previously, without the floats already inflated
We had an AS332 ditch in swedish air force in 2005, they did not deploy the floats until the heli already was down on the water. They hit the sea with high vertical speed, low airspeed and high nose. Tail boom broke of and sank. Heli stayed on surface, did not turn upside down.
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Haverirapport - HKP 10 - H91 (pic of the heli)
