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Vuichard again

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Vuichard again

Old 6th Apr 2022, 12:59
  #61 (permalink)  
 
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HeloNorth
I am really curious so what were the parameters of the aircraft when you were told to recover it ? To be precise fwd airspeed and ROD ?
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Old 6th Apr 2022, 13:16
  #62 (permalink)  
 
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Originally Posted by Hughes500 View Post
HeloNorth
I am really curious so what were the parameters of the aircraft when you were told to recover it ? To be precise fwd airspeed and ROD ?
It has been the same at all the operators I have worked for, how I was originally taught and how I instructed: climb to minimum 2,000 AGL, bleed off all the airspeed while keeping some power applied and wait for the shudder. Watch the VSI for the descent. The bottom drops out pretty fast. Do the recovery of your choice. I used to commonly see 2,000 FPM descent and a loss of 500' before recovery when lowering the collective and using forward cyclic. I have never seen it anywhere close to that using the Vuichard. Once again, the key to this whole thing is early recognition. You 're training as much for the recognition as the recovery.
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Old 6th Apr 2022, 13:41
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Oh helonorth, Airbus does care, because especially in your corner of the world, there will always be somebody to sue the one with money. Airbus does have to cover their backs and that is why they wrote this:

The “classical technique” is effective in avoiding penetration beyond the incipient stage of VRS. However, the “Vuichard recovery technique” may be applied in case of early warning detection in specific operational conditions like rear wind in final approach or helicopter in front of an obstacle.

... and this:Quote:
Airbus Helicopters has performed tests to gather data for a more complete understanding of the aerodynamic loads on the helicopter. Airbus Helicopters does not consider VRS as a normal part of the flight domain of any rotorcraft. Dynamic loads on some components of the rotor system increase significantly in full VRS and are not completely taken into account in the components service life. As an aircraft manufacturer, we do not recommend to place the helicopter in fully developed VRS.
... and this:
Quote:
Recovery technique from fully developed VRS should not be practiced in flight. However, it could be performed without risk in a flight simulator if this one is considered as realistic enough. In flight simulator, both “classical technique” and “Vuichard technique” may be trained.

and this:
Quote:
In flight, in case the pilot has not recognized the early warnings and is in a fully developed VRS, the “classical technique” is effective for the recovery.
However, the “Vuichard recovery technique” may be applied in case of fully developed VRS in specific operational conditions like rear wind in final approach or helicopter in front of an obstacle.
Airbus Safety Information Notice 3463-S-00

And in the incipient stage it doesn't really matter, well except if you have something dangling from the belly, are in SWP not VRS or like Hughes500 are looking at the sky instead of the horizon.
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Old 6th Apr 2022, 13:44
  #64 (permalink)  
 
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Originally Posted by [email protected] View Post

Vuichard is a con but people see a way of monetising the threat of VRS with a 'training' package to save you from it - what a world we live in..............
How is anybody going to make money off of this? Number of views from a Youtube video? It's a simple maneuver, taught by any instructor.
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Old 6th Apr 2022, 13:56
  #65 (permalink)  
 
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So you did not realise, the Vuichard is travelling the world, selling training courses to various companies, organising trainings with flight school where the students pay money to see him? He has his own website where you can book him.
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Old 6th Apr 2022, 14:06
  #66 (permalink)  
 
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Originally Posted by Rotorbee View Post
Oh helonorth, Airbus does care, because especially in your corner of the world, there will always be somebody to sue the one with money. Airbus does have to cover their backs and that is why they wrote this:

The “classical technique” is effective in avoiding penetration beyond the incipient stage of VRS. However, the “Vuichard recovery technique” may be applied in case of early warning detection in specific operational conditions like rear wind in final approach or helicopter in front of an obstacle.

... and this:Quote:
Airbus Helicopters has performed tests to gather data for a more complete understanding of the aerodynamic loads on the helicopter. Airbus Helicopters does not consider VRS as a normal part of the flight domain of any rotorcraft. Dynamic loads on some components of the rotor system increase significantly in full VRS and are not completely taken into account in the components service life. As an aircraft manufacturer, we do not recommend to place the helicopter in fully developed VRS.
... and this:
Quote:
Recovery technique from fully developed VRS should not be practiced in flight. However, it could be performed without risk in a flight simulator if this one is considered as realistic enough. In flight simulator, both “classical technique” and “Vuichard technique” may be trained.

and this:
Quote:
In flight, in case the pilot has not recognized the early warnings and is in a fully developed VRS, the “classical technique” is effective for the recovery.
However, the “Vuichard recovery technique” may be applied in case of fully developed VRS in specific operational conditions like rear wind in final approach or helicopter in front of an obstacle.
Airbus Safety Information Notice 3463-S-00

And in the incipient stage it doesn't really matter, well except if you have something dangling from the belly, are in SWP not VRS or like Hughes500 are looking at the sky instead of the horizon.
You seem to really want to read something in the notice that's not there. They say use the Vuichard if you need it. To me, the main takeaway is they definitely don't want you training full blown VRS with either method. Since the Vuichard is the more effective method, that's what I will do. I like recovering sooner rather than later but I'm funny that way.
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Old 6th Apr 2022, 14:09
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Originally Posted by Rotorbee View Post
So you did not realise, the Vuichard is travelling the world, selling training courses to various companies, organising trainings with flight school where the students pay money to see him? He has his own website where you can book him.
Fine. So what. Can you add full power, left pedal and right cyclic? Congratulations, you can now perform the Vuichard method, free of charge.
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Old 6th Apr 2022, 15:32
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Oh my, helonorth, now you are reading something I never wrote. I always said, that if the method get’s you out of trouble, use it (as does airbus, but they caution you to use it in certain scenarios only). The points most of us are making, are:

a. Nobody has flown independent flight tests with all the necessary instrumentation to lock at all the aspects AND PUBLISHED THE FINDINGS IN A SCIENTIFIC PAPER. For example, some of us are concerned, that the blade flapping, already excessive in VRS (the aerodynamics are really a mess and not completely understood to this day), might become even worse and the blades might get too close to the tail boom in that regime.

b. That in case you have SWP and not (yet) VRS, you make it even worse with the Vuichard method. The classical method get’s you out of both. The Vuichard method is really not a good idea if you have no more power left. (Yeah, I know, bad planning if you don’t have always some power left)

c. As Robbie said from his own experience, when you get in there, especially as a relatively new pilot, the stress level might be too high, to do all the mental decisions in a short time. The classical method is so easy and logical and just works, too. Even experiences pilots can be overwhelmed with everything else going on. For example in one of the accidents, the pilot tried to make a precautionary landing because of some funny noises from the engine or the gearbox. In that case, all of us have limited mental capacity and must rely on as simple procedures as possible. When he could not control the descent rate, he flew straight and touched down hard, but stayed upright. Imagine flying sideways with a possibly broken engine close to the ground.

d. If you use what you learned as you describe it, in an H120, H125, H130, H155, H160, H175, H215, H225 or anything MiL, you’r in for a surprise, because you would have pushed the wrong pedal. And since many pilots switch between types of helicopters, every time they would have to think about which pedal to push. That’s not something you want to do in a high stress situation. I wonder what the KA-32 does.

e. In some some aerial applications, like sling loading, you create a whole bunch of new problems going sideways (and the load the other way).

f. The whole VRS danger has been blown out of proportion. There aren’t thousands of fatal accidents from VRS. There are thousands of accidents from SWP, but that is not a problem Vuichard’s method solves. On the contrary, it might make it worse.

That’s what we are discussing here. While I and others (even Crab is open to it, I think) accept, that you can get out of VRS faster, there are other factors to consider, which makes us question the viability Vuichard’s method, not a least the problem with the not completely understood aerodynamics.
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Old 6th Apr 2022, 15:40
  #69 (permalink)  
 
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Helonorth - next time you do it - same conditions of entry you were using on these training course - just add full power and see what happens.

You will almost certainly recover as quick if not quicker than with the Vuichard technique.

Why? Because you are in the very early stages of VRS (you recognised it early because you put yourself into it) and pretty much any recovery technique will work.

The only reason you compare it to the 'standard' recovery so unfavourably is because the 'standard' technique is the ONLY one that works in fully developed VRS and therefore it was taught for any VRS conditions.

Guess what? If you lower the lever and push the nose forward, the RoD increases and you lose a lot of height compared to raising the lever and cross-controlling.

But also guess what? If you are in full VRS, the 'standard' technique is the only one that is going to save you.

Now if you think this 'new' training will help if, heaven forbid, you do actually enter full VRS then you are going to be sadly disappointed.

Go and try your 'new' technique but hold the shudder until the VSI starts to point hard down and see how good it is. - In fact don't do that as you will probably crash.

Light helicopters with lower disc loadings are more susceptible to VRS as their downwash speed is lower and it takes less RoD to catch it up and ingest it.

All Vuichard is doing is selling early recognition - something that has always been taught - and added a twist to make it look and sound sexy.
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Old 6th Apr 2022, 15:41
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Well all that is happening with a 500ft minute rate of descent ( and < 20 kts )is you are going down. The shuddering you are feeling is the loss of translational lift and ones own inability to transition from fwd flight to a hover with almost no reference points . Go try that again with an ROD of 500 ft a minute, this time pull power and watch the aircraft climb out of it.( As Nick Lappos said " the aircraft is muscling its way out of it ). You havent caught up your downwash so are not in or close to vortex ring. Come over to the Uk and I will show you exactly that in a 300
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Old 6th Apr 2022, 15:41
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You're making an approach to a rooftop. You have maybe 30kts showing on your airspeed indicator and a high rate of decent. You are making this approach downwind and the heafty tail wind has caused the rotor to lose ETL. Combined with the high rate of decent you find yourself in the vortex ring state.

Will Vuchard get you out of this?
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Old 6th Apr 2022, 15:48
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As Rotorbee says - if Vuichard had found a magic bullet to avoid SWP (er perhaps good planning, power awareness and handling) then he might have something to bring to market.
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Old 6th Apr 2022, 15:50
  #73 (permalink)  
 
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Seems like us dinosaurs all seem to think the same thing
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Old 6th Apr 2022, 15:54
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... and we have survived much longer than any mammal.
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Old 6th Apr 2022, 16:05
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Geez Robbie, good question. You'r in deep sh*** there. How high are you over the roof top? Can you avoid crashing on the rooftop by using Vuichard by going sideways? Rather crash on the roof top and not falling of it?
Do you have power left or is the RPM already decaying? Why are you downwind anyway? Obstacles? Probably you shouldn't have tried that approach in the first place. That would be the right solution. Planning and avoiding.
No really, can't say I would know.
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Old 6th Apr 2022, 16:39
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Originally Posted by Robbiee View Post
You're making an approach to a rooftop. You have maybe 30kts showing on your airspeed indicator and a high rate of decent. You are making this approach downwind and the heafty tail wind has caused the rotor to lose ETL. Combined with the high rate of decent you find yourself in the vortex ring state.

Will Vuchard get you out of this?
Good question! Probably, but you were an idiot to get yourself into this spot and I hope whatever it is you do, you don't end up crashing.
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Old 6th Apr 2022, 16:42
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Originally Posted by [email protected] View Post
As Rotorbee says - if Vuichard had found a magic bullet to avoid SWP (er perhaps good planning, power awareness and handling) then he might have something to bring to market.
Looks like the goal posts have been moved all the way out to the parking lot. Anything else?
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Old 6th Apr 2022, 16:50
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Looks like the goal posts have been moved all the way out to the parking lot. Anything else?
yes, you don't actually have a reasoned counter-argument to our assertions regarding Vuichard technique. Other than that you are smack on topic..........
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Old 6th Apr 2022, 17:03
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Originally Posted by [email protected] View Post

But also guess what? If you are in full VRS, the 'standard' technique is the only one that is going to save you.
You don't know this and you are guessing. Early recognition and the Vuichard method will get you out faster. Ever been in a helicopter at the onset of VRS and did the normal recovering and sat there while nothing happened? But sure, tell me how pushing that mush cyclic forward in full on VRS is going to save your ass in time.
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Old 6th Apr 2022, 17:07
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Originally Posted by Rotorbee View Post
Geez Robbie, good question. You'r in deep sh*** there. How high are you over the roof top? Can you avoid crashing on the rooftop by using Vuichard by going sideways? Rather crash on the roof top and not falling of it?
Do you have power left or is the RPM already decaying? Why are you downwind anyway? Obstacles? Probably you shouldn't have tried that approach in the first place. That would be the right solution. Planning and avoiding.
No really, can't say I would know.
Its from video footage of an R44 accident they show at the Robinson Course. They were downwind to get the best angle for a photo shoot (they were the ones being videoed making an approach to the roof of a new hotel).

They hit the roof hard, slid across into dynamic rollover and fell off the other side. Everyone died. Its assumed the pilot didn't realize he was in vortex ring, plus this was long before Vuchard was a thing in the Robby world.

They attributed it to the vortex ring state (as at one point you can clearly see the rate of decent increase significantly) yet they still appear to have forward momentum.

We always practice the recovery from a HOGE into a vertical decent, so it got me wondering if this new sideways hop would still work if you had some forward momentum?
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