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Old 19th February 2016 | 15:04
  #16 (permalink)  
FH1100 Pilot
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Joined: Nov 2006
Posts: 803
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From: Pensacola, Florida
I get what Tourist is asking: If the RoD in VRS is *higher* than an autorotative descent, wouldn't lowering the pitch completely and entering a zero-speed auto reduce your RoD and return cyclic control?

Answer: P-r-o-b-a-b-l-y...but there are a lot of variables. If you've allowed FDVRS to develop, then transition back to zero-airspeed auto is going to take some time. And when you're plummeting to earth at 2000 fpm or greater you don't really have a lot of time to play with. If it's "just" IVRS, then lowering the collective fully and pushing the nose down is going to give you a serious rate of descent.

These discussions are largely theoretical. Prouty admits that the air and airflow through a rotor is so chaotic that wind-tunnel testing of VRS models is not really super-accurate. The airframe of the little model helicopter does not move in the environment like a full-scale helicopter in the real world. The wind tunnel air is pretty constant, unlike that produced by Mother Nature.

Secondly, nobody gets into FDVRS way up high with lots of altitude and time in which to recover. If you ever did, then it really doesn't matter which technique you choose.
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