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Old 17th Dec 2010, 10:12
  #69 (permalink)  
topendtorque
 
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As a more extreme example of this I'd like to refer the Nick Lappos statement that given sufficient power one can get out of VRS using power.
did he really say that? That bloke in the blackhawk crash onto the ship had all the power in the world and he just sank faster, didn't he? before he realized and then put the cyclic forward.

certainly the use of a swift flick on the collective will change the nice little formula for VRS that Nick has oft described if you manage to get it in the incipient stage. That's when or even before you first feel that sinking sensation, but immediately thereafter you will be sitting with an over pitched problem. Usually which is beyond the available power to sustain, so, recovery as per cattle truck's definition.

most mustering pilots encounter this little problem somewhere in their early career too close to the ground to lower collective and fly away, if they are lucky and the ground bump is not too hard after perhaps another savage pull on the ol' life saver and with no obstructions for the spinning bits they get to live and learn.

an it's lead with throttle and the engine and rotor RPM should stay together there cattletruck, less you have a very worn out set of belts or roll off too much throttle?

HOGE depends entirely on weight, altitude and OAT, recently did an excercise where a Raven I at 2300lbs would have hovered OGE about 300 feet below where it was sitting firmly fixed to the ground only 1200' above sea level.

the old recip rule of thumb was HIGE MAP+ up to 1" running to normal take off, +2" to +3" normal to steep take, I.E. getting up to setting AS for max angle of sustained climb, +4" to +5" perhaps a vertical, slowly.

in fact you should be able translate with just less that 1/2" more than HIGE from the IGE hover. try it, lotsa people have lost a carton of beer at it. keep the bloody stick still, as gordy says.

The 44 should gain an inch of MAP for every 100 lbs that is thrown off, or pick up 100 lbs extra for every 1' spare for the take off required.

possibly none of which applies to this case.
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