Are engine failures always recoverable in helicopters?
Assuming there's a large flat space on which to land, are engine failures always recoverable in a helicopter? I read on another site that an engine failure below 90 feet AGL or so is sure to result in a crash. I've heard of autorotation but don't know much about it, nor do I know much about helicopter flying in general. So, assuming a good pilot and flat terrain on which to land, how hard is it to land safely after a powerplant failure (everything else intact, just a total loss of power)?