R44 Poh 9-10.4
Power Failure 8 feet & 500 feet AGL
Autorotation to water:
1 Lower collective immediately to maintain rotor RPM
2 Reduce airspeed to below 80 KIAS
3 If altitude permits, maneuver into wind
4 Inflate floats
NOTE - Float inflation may take up to three seconds. Squeeze lever early enough to allow full inflation before water contact
No minimum alt. to inflate, but work a timeline backwards from water contact and you'll get an estimated minimum alt. to do 1 to 4 sucessfully......