Oh no, 20 to 30 feet.
But let's assume they had 1500ft/min ROD which is more realistic in the R22 and that would be just 17mph.
That is a mere 3.17m/s^2
Possible. It is a third of one g. Around 19deg of bank? Not something that folds the blades.
But that is with instruments that lag and the human eye. It would be interesting to use one of flight recorders for sail planes to get a more accurate reading.
With your numbers it would be 7.62m/s^2 and it would take about two seconds, until the descend stops. Not unheard of.
Last edited by Rotorbee; 18th Feb 2016 at 14:10.
Reason: New numbers.