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Old 26th May 2004 | 13:16
  #36 (permalink)  
Gaseous
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Joined: Nov 2001
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From: Alderney or Lancashire UK
Jcooper
The idea is to roll out of the turn before you hit, however landing sites and all sorts of other variables count. On the other hand if the choice is land in a turn or with 8000 fpm ROD, NR at 0%and your aircraft and corpse spread thinly about, what is your choice then?

Autorotation is about energy management. A helicopter with a dead engine has 3 stores of energy.

1) potential energy (height)
2) kinetic energy (airspeed and to a lesser extent ROD)
3) more kinetic energy (RRPM)

The total energy in the system is more than is required to land safely, so the trick is to arrive at the ground with energy in the right place (RPM) and waste the excess (speed and height).

If RPM is low then a flare converts airspeed to RPM. A turn converts height into RPM.

A logical way to do this if RPM is low, other circumstances permitting, would be to turn high, to wind up the rotor system, converting height to RPM, without losing airspeed and save the flare for the end to counter the rate of descent.


Forward cyclic only has a place if you have RPM to spare as unloading the disc turns RPM into airspeed.
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