Hello,
I would like to discuss some interesting info and thoughts.
I know that there are helicopters that can do an auto to the ground
perfectly soft with no airspeed and no flare.
I know somebody who did it in an R44.
Then I heard somebody telling about one in a R22 with two persons,
piloted - of course - by TT. I couldn't believe and neither could any
colleague.
But I did some quick calculations and if there is no big mistake, it is
theoretically easily possible. Of course there is the timing issue ;-) I
don't want to try it.
I took the 100HPsec (rotor energy at 104%) out of the R22 flight
training guide and converted them to 74 kJ.
The kinetic energy in a 1200lbs R22 descending at 1500ft/min translates
to only 16kJ. Even at 1370lbs and 2000 ft/min it is still less than half
(namely 31 kJ) of the energy in the rotor at 104%!!!
Of course you cannot get out 100% of the rotor energy, only down to
about 80% at sea level and aerodynamic efficiency is bad. But hey, you
can go up to 110% and at 1200lbs it is only 16 kJ, less than a quarter
of the rotor energy.
I do not want to have anyone try it, but has anyone here ever done such
a thing in any helicopter?
I'm NOT talking about the dead man's curve!!!
I'm talking about a perfectly established auto with zero airspeed at
high rotor rpm which needs several hundred feet for establi****ng!
There is no way to assume one could do it after an engine failure in
300ft AGL at 20kts!!!
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