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Vuichard again

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Vuichard again

Old 1st Nov 2019, 05:18
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Vuichard again

The FAA has just published a new edition of the Helicopter Flying Handbook, which gives pride of place to Vuichard for recovery from incipient Vortex Ring (page 11-10). Given the popularity of Vuichard shown on this forum, I thought people might find that interesting.

The reaction on the FB helicopter pilot group has been 100% positive of the form "hey, awesome Claude". Personally I have no opinion, but then I only fly R44s in which the concept of having an excessive of power is something to dream about.

https://www.faa.gov/regulations_poli...a/hfh_ch11.pdf

Happy reading!
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Old 1st Nov 2019, 06:39
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well at last the correct terminology has been used ie incipient vortex ring
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Old 1st Nov 2019, 07:16
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And also this
Vortex Ring State Vortex ring state (formerly referenced as settling-with power) describes an aerodynamic condition in which a helicopter may be in a vertical descent with 20 percent up to maximum power applied, and little or no climb performance. The previously used term settling-with-power came from the fact that the helicopter keeps settling even though full engine power is applied.
They have finally acknowledged the difference!!!
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Old 1st Nov 2019, 07:23
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But
If altitude is sufficient, some time can be spent in the vortices, to enable the pilot to develop a healthy knowledge of the maneuver. However, helicopter pilots would normally initiate recovery at the first indication of vortex ring state. Recovery should be initiated at the first sign of vortex ring state by applying forward cyclic to increase airspeed and/ or simultaneously reducing collective. The recovery is complete when the aircraft passes through effective translational lift and a normal climb is established.
Having expounded the Vuichard recovery technique for full VRS - they then go back to the 'traditional' recovery for IVRS which is surely the wrong way round.
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Old 1st Nov 2019, 08:50
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The recovery is complete when the aircraft passes through effective translational lift and a normal climb is established
Why is there any need to climb? To enter the VRS the aircraft was descending in the first place, so simply recovering to level flight (initially) should be sufficient.
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Old 1st Nov 2019, 09:04
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It's in the context of training and demonstrations.
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Old 1st Nov 2019, 15:17
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Originally Posted by [email protected] View Post
But Having expounded the Vuichard recovery technique for full VRS - they then go back to the 'traditional' recovery for IVRS which is surely the wrong way round.
Well it worked for me when I got into it a few years ago.
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Old 29th Mar 2022, 18:46
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Be careful of the Vuichard technique - it isn't all that it is cracked up to be.
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Old 29th Mar 2022, 23:38
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Originally Posted by RVDT View Post
Be careful of the Vuichard technique - it isn't all that it is cracked up to be.
I think most of us worked that out early on.
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Old 30th Mar 2022, 00:48
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Originally Posted by 212man View Post
I think most of us worked that out early on.
Care to share fellas, 'cause they're presenting it to us as the greatest thing since sliced bread.
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Old 30th Mar 2022, 01:37
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Originally Posted by Robbiee View Post
Care to share fellas, 'cause they're presenting it to us as the greatest thing since sliced bread.
You’ve contributed to some of the discussions on Rotorheads before 🤔

Vuichard again

Vuichard technique for settling with power?

Practice Recovery from VRS lately?

State Police Helo Crash Charlottesville Virginia

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Old 30th Mar 2022, 02:18
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Originally Posted by Senior Pilot View Post

So far all I see there is some arguing over SWP vs VRS terminology, not the answer to my question as to what is wrong with the Vuichard Recovery technique?

,...and I'm not sifting through all that to hunt down the answer.
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Old 30th Mar 2022, 05:35
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Originally Posted by 212man View Post
I think most of us worked that out early on.
Myself included - some things need to be reaffirmed on occasion.
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Old 30th Mar 2022, 08:14
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Shawn Coyle

All of the above probably goes into the realm of Wayne Johnson to do the maths, or Gordon Leishman, or may be a topic for Shawn Coyle to comment on. Ray Prouty would have given a solution in short order too in small sentences

Sadly, Shawn Coyle left us in June 2021 - RIP.
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Old 30th Mar 2022, 09:20
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Robbiee - just for you - Vuichard has claimed to recover from fully developed VRS in under 100' - that's not possible. His is an alternative recovery from the very very early stages, incipient incipience of VRS which has no advantage over the standard method.

As has been discussed here, the use of large pedal deflections in Robinsons can cause unwanted secondary effects that can compromise the clearances between MR and the tail boom so why risk it?
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Old 30th Mar 2022, 14:25
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Originally Posted by [email protected] View Post
Robbiee - just for you - Vuichard has claimed to recover from fully developed VRS in under 100' - that's not possible. His is an alternative recovery from the very very early stages, incipient incipience of VRS which has no advantage over the standard method.

As has been discussed here, the use of large pedal deflections in Robinsons can cause unwanted secondary effects that can compromise the clearances between MR and the tail boom so why risk it?
So, are you saying that the Vuichard method isn't all its cracked up to be because it doesn't allow you to recover with less altitude loss, or because it can lead to some issue with the pedals in Robby's I'm not familiar with?
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Old 30th Mar 2022, 15:35
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Well Robbie, while ol' Crab can be really annoying, he knows a thing or two about flying helicopters, and unfortunately he is pretty often right.
We have discussed Vuichard's method a few years ago and there are a issues with it. Not only that he did not invent it. That goes back way before he even touched a stick the first time. But it did not become the method of choice.
If I remember right, SASless mentioned that in a CH-47 it is the method to use and they did not find that out only recently.
It can get you out of a very deep VRS where everything else fails, as was reported by a fellow pilot flying with a test pilot, but I doubt, that any Robinson ever got as deep into VRS, that the controls would be completely ineffective.
The aerodynamics of VRS are complicated, very complicated. By far not as simple as the nice pictures in the common explanations will make you believe.
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Old 30th Mar 2022, 16:10
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Originally Posted by Robbiee View Post
So, are you saying that the Vuichard method isn't all its cracked up to be because it doesn't allow you to recover with less altitude loss, or because it can lead to some issue with the pedals in Robby's I'm not familiar with?
Both Robbiee.
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Old 30th Mar 2022, 21:13
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Originally Posted by [email protected] View Post
Both Robbiee.
Strange, it works for me.
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Old 30th Mar 2022, 21:34
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As I wrote here before in previous discussions on the "Vuichard" recovery technique, the claim made is that it provides a full recovery with a height loss of 100 feet or less. How can it do that from a rate of descent of what is possibly 3,000 feet per minute or more? I've experienced VRS of around that rate of descent in a Puma and it took far, far more height to recover. The aircraft randomly pitched, yawed and rolled until we gained some forward speed by holding full forward cyclic and even then the recovery from the descent couldn't be stopped within 100 feet! During RAF rotary wing training I was shown what was purported to be VRS in a Whirlwind 10 and it was nothing like fully the developed VR state; the aircraft almost recovered by itself with very small control movements.
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