ditching and various sub-topics
A couple of comments about some of the posts:
The question of which way to roll (or not) arises fairly regularly on rec.aviation.rotorcraft and as a result of varying opinions I contacted robinson helicopter company and got the lowdown on their opinion.
I can't speak with any knowledge on other types though.
The theory of some maths whiz pilots was you should impact the blade so the forces would transmit to the MR gearbox and dislodge it backwards, not forwards into the cabin. This would mean a right roll (in counter clockwise turning blades). Some others said "no, the impact needed to be on the left side after a left roll". The maths was a bit over my head when they started getting so contradictory.
Robinson's answer was. "We have tested the theory and none of it applies. Robinson blades bend up and distort or break and the MR gearboxes never dislodged." So they maintain the roll to the left as dictated in their handbook is purely to provide easier exit for the pilot as the aircraft submerges.
I guess if you have a passenger then which way to roll is dependant on whether you think they they will find it easier to get out than you will.
I suspect that some other types of helicopter with beefier blades may have more strict guidelines on rolling to avoid MR gearbox dislodgment.
Floats:
It would be nice to think that the situation would never arise where you would be over water without floats. But reality is there are planty of times where the only place you can land may be wet. A lake, creek or river in a heavily tree covered area, tracking along the coast and have to turn back into the wind and suddenly find your glide distance is a few metres short of the beach etc. In Oz is quite legal for private ops to be over water and out of auto distance provided you have lifejackets on.
Seatbelts:
On one of my many dunker courses we were shown a video with footage and interviews with people who had been in ditchings and their comments were interesting.
Firstly seatbelts. One guy undid his first for the same sort of arguments put forward above. When he touched down with what he thought was a zero speed auto he was slammed into the dash as the real zero speed was reached very rapidly. He was hurt but not enough to stop him getting out. His comment was that your perception is distorted because you are just so busy and stressed. He said he would never undo his belt again till everything stopped in the water.
Water entry and time to get orientated.
Two separate pilots told of how the cabin instantaneously filled with froth. Not a second to get organised and it was completely disorientating because all those suggested things like seeing which way the bubbles rise or things float was no help at all. In full daylight and "clear water" theywere completely blinded by bubbles. Sounds like you need to treat every ditching as the equivalent of a night ditching.
The average time I heard quoted at each course I did was less than 10 seconds from engine problem to swimming clear of the aircraft. Doesn't leave any time for much at all.
My advice 9 for what its worth) is do as many dunker courses as you can. Besides they are great fun.