If the engine fails in the hover (which is only about 4 -5ft), then you don't lower the collective and shove a load of boot in (which boot depends, as Whirly said, on which direction your rotors turn). Raising the collective helps to cushion the landing. Yes you have to be quick though! These failures are regularly practiced and aren't too hairy!

There is an envelope (affectionately known as "The Dead Man's Curve") of height/speed in which one doesn't fly as these are the points where the helicopter designer's think that survival is unlikely. You are taught not fly beneath this curve.

I'd still rather be in a helicopter than a Cessna if there's going to be an engine failure!

I hope that helps.

IO540,
In an R22, if you do nothing else, you have about 2 seconds to lower the collective. But if you flare as well, which also raises the RRPM, you have about 7 seconds - I know someone who's tested this. That's not a lot of time, but it should be enough...most people's reaction time is far quicker than this. So this is what we teach students - lower the lever and back on the cyclic. And we practise it lots!

And in the climb, whirly?

QDM x 3,

No difference. Don't forget that in a helicopter the cyclic controls the attitude and airspeed, and the collective controls height. So to climb, you don't point the nose upwards; you raise the collective. So if the engine fails, you still flare and lower the collective.

The only time it could be a real problem is if the engine fails after takeoff, when you really, really don't have a lot of time. But this applies to any aircraft, doesn't it?

Have I understood your question - and what you're thinking - correctly, QDM? I wasn't sure.