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Old 1st Dec 2017, 09:14
  #138 (permalink)  
ShyTorque

Avoid imitations
 
Join Date: Nov 2000
Location: Wandering the FIR and cyberspace often at highly unsociable times
Posts: 14,580
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Rotorbee, one thing is for certain, I'm sure my "cockie" is different to yours. But from your last reply I'm not sure if you're uniformed or uninformed.

I have no axe to grind either way on this subject (life's too short to get my undies in a bunch about it) which is why I wrote my initial post (#2) on this thread.

But my thoughts; how about:

The approaching IGE situation.
1: "Under pitching" = not pulling enough power early enough to arrest a high ROD at very low IAS near the ground.
2: SWP= following situation 1, you pull to all the power you've got, too late - you keep on going down!
3: Over pitching = what follows from 2. No more engine power, but you can't stop your left hand from pulling pitch!

The OGE situation.
1: Under pitching = as per 1 above, but OGE.
2: SWP / IVRS. As per 2 above, but you don't have the visual cues and the ROD builds. The airflow through the disc begins to recirculate but you could fly away because you still have good cyclic response (Vuichard technique might work here). Call it IVRS if you prefer.
3: Fully developed VRS. Use whatever technique you like to regain some forward speed to stop the recirculation, but you are going to lose a lot of altitude because you no longer have good cyclic response, the aircraft will be pitching and rolling all by itself and your ROD will be higher than you've ever seen before. You can forget all about a recovery in "20 to 30 feet" as I read in an article about the Vuichard technique!
Most helicopters are rigged with more pitch control than roll control. We Brits prefer to use forward cyclic, and lots of it.

I'm off to work very soon (late shift today) so can't participate further. Obviously, as usual I'll be avoiding situation 1 above so the subject won't crop up in practice.
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