Vuichard technique for settling with power?
Going back to your original post - you were referring to SWP which, as we have discussed at length, is not IVRS or VRS.
So, consider your circumstances - you were trying to hover OGE with clearly limited power available (up at the red line you said) so how does the Vuichard technique get you out of that?
The amount of collective you have available is minimal (red line) and applying full power pedal just saps more power. All sideslipping to the right achieves is getting translational lift to the MR which you could get by just moving the cyclic forward instead.
Then, when the vertical component of your Total Rotor Thrust is the only thing opposing your weight, you tilt it, thus reducing the vertical component even further.
I'm really not sure how this is supposed to help!
All the stuff about reaching the upwind side of the vortex is more bollocks because you aren't in VRS, you have just run out of power.
The BIG problem is that many less experienced pilots reading this forum will think there is a magic bullet recovery for IVRS or VRS when the only guaranteed way is to avoid it altogether.
If you want a proper top tip then only approach a hover OGE level rather than descending to it - when you are limited on power it is much easier to assess your real power demand as you approach the hover as you are not trying to arrest RoD and forward speed. As you start to reach your power limit then ease the cyclic forward and fly away if you have any concerns.
So, consider your circumstances - you were trying to hover OGE with clearly limited power available (up at the red line you said) so how does the Vuichard technique get you out of that?
The amount of collective you have available is minimal (red line) and applying full power pedal just saps more power. All sideslipping to the right achieves is getting translational lift to the MR which you could get by just moving the cyclic forward instead.
Then, when the vertical component of your Total Rotor Thrust is the only thing opposing your weight, you tilt it, thus reducing the vertical component even further.
I'm really not sure how this is supposed to help!
All the stuff about reaching the upwind side of the vortex is more bollocks because you aren't in VRS, you have just run out of power.
The BIG problem is that many less experienced pilots reading this forum will think there is a magic bullet recovery for IVRS or VRS when the only guaranteed way is to avoid it altogether.
If you want a proper top tip then only approach a hover OGE level rather than descending to it - when you are limited on power it is much easier to assess your real power demand as you approach the hover as you are not trying to arrest RoD and forward speed. As you start to reach your power limit then ease the cyclic forward and fly away if you have any concerns.
Jymil
To get out of fully developed VR I think it is luck only, in my case it certainly was or perhaps desperation by using the tail rotor as there was no other option left.
All I can say is never never get into the situation in the first place ! This should be the real mantra of this thread. Now if The Vulchard technique gets you out of incipient state then great, but you shouldn't have really got thee in the first place.
To get out of fully developed VR I think it is luck only, in my case it certainly was or perhaps desperation by using the tail rotor as there was no other option left.
All I can say is never never get into the situation in the first place ! This should be the real mantra of this thread. Now if The Vulchard technique gets you out of incipient state then great, but you shouldn't have really got thee in the first place.
Let's recap for a moment.
Until now we have found out, that the Vuichard technique isn't new. He has rediscovered it.
I searched for a paper he might have written, no luck. Which makes me wonder why, since there is a claim, that the Swiss FOCA was involved. Who knows, the experts there might not be as impressed as Vuichard himself, but keep quite.
Vuichard isn't a test pilot and afaik, the Swiss FOCA does not employ one.
Neither is Tim Tucker.
To my astonishment, it suddenly became a hot topic and quite a few pilots describe it as the new thing to save lives. When you read the comments on the R&W website, one gets the impression Tim Tucker saved the universe single handedly. They almost worship him.
Helicopters crash more often due to SWP (that darn sudden power loss
pilots often report afterwards) than due to VRS.
If SWP develops into VRS you are out of luck with that technique. You already use take of power and now you want to go sideways demanding even more power from the already sweating engine.
Somehow it does not add up.
Personally I have done IVRS many times during initial and recurrent training and as a CFI (not as many as some of you, I am sure). It is sometimes pretty hard to get an R22 to drop out of the sky. The worst I ever saw had was about 2000 fpm (with a lot of air below me, not only 1000ft). That isn't a fully developed one.
Getting out of it was merely a matter of shoving the stick forward (yes, I have lowered the collective to keep examiners happy, but sometimes one just tries to do something slightly different) and that isn't new either, because some papers suggest exactly that to minimise altitude loss.
Thinking back, I might even have kept the stick very much to the aft, for keeping it in the IVRS. It might be possible, that without changing the position of the cyclic the R22 would fly it self out of it... probably and getting back in shortly after. This might be due to the horizontal stabiliser being behind the rotor disk.
Just once I had a real situation which I realised as a very, very early stage of IVRS. While approaching Palmer AK I got this feeling were all the controls become sluggish and the airframe shudders. A bit more speed down to the runway solved that. Interestingly the windsock on the left showed a head wind, the one on the right tailwind, which I saw later. But that is Palmer for you, where a headwind is a somewhat surprising occurrence that makes you uneasy.
While googeling for more information I found THIS.
Reading that, it seems the author is pretty sure you can get into VRS with 300 fpm and overpitching (SWP) while experiments and the 206 chart suggest more like 800 fpm. Which makes me thinking, has anyone ever tried all the techniques in a controlled environment? I doubt that. Looking at an altimeter and VSI with all their lag and installation error does not prove a lot. I could even imagine a temporary effect on the instruments depending if you side-slip or not and with all the downwash hitting the fuselage, the standard instruments might not be very reliable.
The Vuichard technique might just be a variant of another standard technique I read about. In the early stage, just use a lot more power to fly out of it ... if you have. Nick Lappos suggested that the S 64 had so much power it would go upwards in no time at all. A B3 might do the same.
I personally think that the Vuichard technique isn't any better in getting out of it in a very early stage, when the ship just starts to shudder and the controls are all mushy, because when you shove the stick forward not to aggressively you don't loose a lot of altitude if any. In that moment the terrible plunge to hell hasn't even started. Waiting to let the VRS develop a bit more isn't real life. When the whole ship shudders and acts like a rodeo horse and the cows get bigger, even the most daft pilot must realise, that something went wrong a lot earlier. Or shouldn't he?
Having said that, I am immediately proven wrong. REGA had an accident lately, where VRS seems to be the culprit (rumour). The 109 K2 hit the ground pretty hard, tore off the undercarriage and landed on its belly, but stayed upright. It seems it was a tailwind approach that went wrong (stand corrected here, the accident report isn't out yet). Now imagine the pilot would have initiated a side-slip in that situation and hit the ground sideways? Not a nice picture. Depending on the weather and other factors, one will not realise what is going on and one might get quite far into IVRS without clear clues and the moment he does, it might even be too late for the Vuichard technique, if it helps at all. To suggest that the whole point is not getting into it, is correct, but not the reality. You only have to look at the wrong windsock once.
I don't know what the pilot did wrong, but I think he did one thing right. He flew his ship into the crash and it stayed upright. With the Vuichard technique he would have a much harder time to keep the ship upright. Flying sideways at high speeds descending to the ground isn't something I would like to do.
Since nobody ever tried to measure the different techniques and write down the results, we are all discussing something that is merely an idea with some indications from standard instruments without taking into account any aerodynamic and other effects on the helicopter or the pilot. To prove anything, I'd like to see some more evidence, please.
The standard technique is easy, works and does not need more power, while the Vuichard technique is more difficult to master and needs more power, which one probably does not have.
Let's look at another scenario. Imagine you are flying a load on the hook and during the approach you get into IVRS. Pickling the load would solve the problem immediately. Lots of power left but an unhappy customer. Using the Vuichard technique would let the load swing suddenly all over the place. Endangering people on the ground who thought, standing not in the flight path of the helicopter would be save. The pilot not only has to catch the descend, but also the swing of the load. Shoving the stick forward and going around using the predefined escape route more or less straight ahead (I know, it isn't always that simple) seems a lot easier to control. Even if he has to let go of the load, its impact point would be a lot more predictable.
Frankly, I wouldn't say that the Vuichard technique is bollocks, but neither new nor the best way to save my day. As a last resort it might be just the thing.
Until now we have found out, that the Vuichard technique isn't new. He has rediscovered it.
I searched for a paper he might have written, no luck. Which makes me wonder why, since there is a claim, that the Swiss FOCA was involved. Who knows, the experts there might not be as impressed as Vuichard himself, but keep quite.
Vuichard isn't a test pilot and afaik, the Swiss FOCA does not employ one.
Neither is Tim Tucker.
To my astonishment, it suddenly became a hot topic and quite a few pilots describe it as the new thing to save lives. When you read the comments on the R&W website, one gets the impression Tim Tucker saved the universe single handedly. They almost worship him.
Helicopters crash more often due to SWP (that darn sudden power loss
pilots often report afterwards) than due to VRS.If SWP develops into VRS you are out of luck with that technique. You already use take of power and now you want to go sideways demanding even more power from the already sweating engine.
Somehow it does not add up.
Personally I have done IVRS many times during initial and recurrent training and as a CFI (not as many as some of you, I am sure). It is sometimes pretty hard to get an R22 to drop out of the sky. The worst I ever saw had was about 2000 fpm (with a lot of air below me, not only 1000ft). That isn't a fully developed one.
Getting out of it was merely a matter of shoving the stick forward (yes, I have lowered the collective to keep examiners happy, but sometimes one just tries to do something slightly different) and that isn't new either, because some papers suggest exactly that to minimise altitude loss.
Thinking back, I might even have kept the stick very much to the aft, for keeping it in the IVRS. It might be possible, that without changing the position of the cyclic the R22 would fly it self out of it... probably and getting back in shortly after. This might be due to the horizontal stabiliser being behind the rotor disk.
Just once I had a real situation which I realised as a very, very early stage of IVRS. While approaching Palmer AK I got this feeling were all the controls become sluggish and the airframe shudders. A bit more speed down to the runway solved that. Interestingly the windsock on the left showed a head wind, the one on the right tailwind, which I saw later. But that is Palmer for you, where a headwind is a somewhat surprising occurrence that makes you uneasy.
While googeling for more information I found THIS.
Reading that, it seems the author is pretty sure you can get into VRS with 300 fpm and overpitching (SWP) while experiments and the 206 chart suggest more like 800 fpm. Which makes me thinking, has anyone ever tried all the techniques in a controlled environment? I doubt that. Looking at an altimeter and VSI with all their lag and installation error does not prove a lot. I could even imagine a temporary effect on the instruments depending if you side-slip or not and with all the downwash hitting the fuselage, the standard instruments might not be very reliable.
The Vuichard technique might just be a variant of another standard technique I read about. In the early stage, just use a lot more power to fly out of it ... if you have. Nick Lappos suggested that the S 64 had so much power it would go upwards in no time at all. A B3 might do the same.
I personally think that the Vuichard technique isn't any better in getting out of it in a very early stage, when the ship just starts to shudder and the controls are all mushy, because when you shove the stick forward not to aggressively you don't loose a lot of altitude if any. In that moment the terrible plunge to hell hasn't even started. Waiting to let the VRS develop a bit more isn't real life. When the whole ship shudders and acts like a rodeo horse and the cows get bigger, even the most daft pilot must realise, that something went wrong a lot earlier. Or shouldn't he?
Having said that, I am immediately proven wrong. REGA had an accident lately, where VRS seems to be the culprit (rumour). The 109 K2 hit the ground pretty hard, tore off the undercarriage and landed on its belly, but stayed upright. It seems it was a tailwind approach that went wrong (stand corrected here, the accident report isn't out yet). Now imagine the pilot would have initiated a side-slip in that situation and hit the ground sideways? Not a nice picture. Depending on the weather and other factors, one will not realise what is going on and one might get quite far into IVRS without clear clues and the moment he does, it might even be too late for the Vuichard technique, if it helps at all. To suggest that the whole point is not getting into it, is correct, but not the reality. You only have to look at the wrong windsock once.
I don't know what the pilot did wrong, but I think he did one thing right. He flew his ship into the crash and it stayed upright. With the Vuichard technique he would have a much harder time to keep the ship upright. Flying sideways at high speeds descending to the ground isn't something I would like to do.
Since nobody ever tried to measure the different techniques and write down the results, we are all discussing something that is merely an idea with some indications from standard instruments without taking into account any aerodynamic and other effects on the helicopter or the pilot. To prove anything, I'd like to see some more evidence, please.
The standard technique is easy, works and does not need more power, while the Vuichard technique is more difficult to master and needs more power, which one probably does not have.
Let's look at another scenario. Imagine you are flying a load on the hook and during the approach you get into IVRS. Pickling the load would solve the problem immediately. Lots of power left but an unhappy customer. Using the Vuichard technique would let the load swing suddenly all over the place. Endangering people on the ground who thought, standing not in the flight path of the helicopter would be save. The pilot not only has to catch the descend, but also the swing of the load. Shoving the stick forward and going around using the predefined escape route more or less straight ahead (I know, it isn't always that simple) seems a lot easier to control. Even if he has to let go of the load, its impact point would be a lot more predictable.
Frankly, I wouldn't say that the Vuichard technique is bollocks, but neither new nor the best way to save my day. As a last resort it might be just the thing.
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The accident report on the Rega crash is not yet out but since this is a rumor network: some people think this accident was exactly preventable with VT and the pilot should have been fired.
No wonder. VT was in probably every Swiss magazine. Since it is a Swiss technique, it must be better than anything else ever invented elsewhere. When it comes from Switzerland, it is from a higher authority. Therefore a Swiss pilot must use it if appropriate or not, or else ...
When you look at the following picture, there are a few clues, that he did a good job.
http://www.snoop.ch/img/5117761424968557.jpg
He landed on the grass and the wheels just broke of. The landing must have been pretty hard, but not hard enough to bend the blades to touch the tail boom. If at all it was IVRS at a very early stage with a pretty low sink rate or he had just not managed to get out of it with a lot of power. Not a lot of forward speed either, because the wheels are still there and no sliding marks. An almost perfect hard landing.
Another picture. The windsock in the back shows a wind which is perpendicular to the helicopter. If the wind did not turn until that picture was taken, that would be a side wind.
He PROBABLY came in fast (knows the corner, did that every time, not the stable approach with a slow deceleration one does to an unfamiliar place) and during the "breaking" with the nose high, things got ugly. That would be at or below hundred feet (assuming, no facts except experience). He probably even was in a turn toward the pad which is in the background.
In that moment trying to do a side-slip would be suicidal, especially using the power pedal. Adding power, yes, levelling the ship, yes, flying uncoordinated, God no. He wouldn't even had time to use VT, because he would have to level the ship first and then try to fly out of it. For that it was definitely too late.
He might have f***ed up the landing but it looks to me, that's a pilot who knows how to save his ass.
When you look at the following picture, there are a few clues, that he did a good job.
http://www.snoop.ch/img/5117761424968557.jpg
He landed on the grass and the wheels just broke of. The landing must have been pretty hard, but not hard enough to bend the blades to touch the tail boom. If at all it was IVRS at a very early stage with a pretty low sink rate or he had just not managed to get out of it with a lot of power. Not a lot of forward speed either, because the wheels are still there and no sliding marks. An almost perfect hard landing.
Another picture. The windsock in the back shows a wind which is perpendicular to the helicopter. If the wind did not turn until that picture was taken, that would be a side wind.
He PROBABLY came in fast (knows the corner, did that every time, not the stable approach with a slow deceleration one does to an unfamiliar place) and during the "breaking" with the nose high, things got ugly. That would be at or below hundred feet (assuming, no facts except experience). He probably even was in a turn toward the pad which is in the background.
In that moment trying to do a side-slip would be suicidal, especially using the power pedal. Adding power, yes, levelling the ship, yes, flying uncoordinated, God no. He wouldn't even had time to use VT, because he would have to level the ship first and then try to fly out of it. For that it was definitely too late.
He might have f***ed up the landing but it looks to me, that's a pilot who knows how to save his ass.
Thread Starter
Injecting life into this old thread (which I started way back)... I flew the R44 with a different instructor today, and he asked "have you ever tried flying out of SWP with lateral cyclic?" Funny really since I think it was a discussion between me and one of their now-departed instructors that got the school interested in the idea.
He said that they'd tried it and got an altitude loss of 100 feet to recover instead of 400 feet with the usual technique. We went out and flew a couple and it certainly worked. Of course this was not from fully-developed SWP, just wait for the descent to start then wait a couple of seconds.
The technique we used was right cyclic, left pedal, pull to 23" of power (max continuous).
He said that they'd tried it and got an altitude loss of 100 feet to recover instead of 400 feet with the usual technique. We went out and flew a couple and it certainly worked. Of course this was not from fully-developed SWP, just wait for the descent to start then wait a couple of seconds.
The technique we used was right cyclic, left pedal, pull to 23" of power (max continuous).
So what height, speed and rate of descent did you start this from?
Did you try it with left cyclic and right pedal (which would have given you more power available)?
Did you try it with left cyclic and right pedal (which would have given you more power available)?
Claude Vuichard is a former transport pilot which has flown thousands of sling operations in the swiss alps. In sling ops your are always very close to the VRS, since you have a lot of descends with 0 or nearly 0 forward speed.
If you are 100 feet or so above ground and a vrs develops, you have no chance to escape with the "collective down and gain airspeed" method, since you will crash straight forward in to ground.
But not only in sling business, also in school- and all other flights, in which flight phase is the greatest danger of vrs? Exactly, in the approach segment when you are very close to the ground. With the old method, the only influence you have, is the influence about the size of the debris field on the crash site.
With the vuichard recovery technique you have a real chance to escape from the vrs, but you have to know the signs to identify it early enough.
If i read posts from peoples who lost 5000ft, i'm wondering what they did in the meantime?!
With the mentioned R44 you have to apply right cyclic and left pedal, since you need to pull max power and keep the nose straight fwd with a lot of left pedal to create the needed TR-thrust.
If you would try to escape to the left, you will need to lower the collective to apply max right pedal. But in this case you will loose much more height!
If you are 100 feet or so above ground and a vrs develops, you have no chance to escape with the "collective down and gain airspeed" method, since you will crash straight forward in to ground.
But not only in sling business, also in school- and all other flights, in which flight phase is the greatest danger of vrs? Exactly, in the approach segment when you are very close to the ground. With the old method, the only influence you have, is the influence about the size of the debris field on the crash site.
With the vuichard recovery technique you have a real chance to escape from the vrs, but you have to know the signs to identify it early enough.
If i read posts from peoples who lost 5000ft, i'm wondering what they did in the meantime?!
With the mentioned R44 you have to apply right cyclic and left pedal, since you need to pull max power and keep the nose straight fwd with a lot of left pedal to create the needed TR-thrust.
If you would try to escape to the left, you will need to lower the collective to apply max right pedal. But in this case you will loose much more height!
With the vuichard recovery technique you have a real chance to escape from the vrs, but you have to know the signs to identify it early enough.
If i read posts from peoples who lost 5000ft, i'm wondering what they did in the meantime?!
If i read posts from peoples who lost 5000ft, i'm wondering what they did in the meantime?!
If you would try to escape to the left, you will need to lower the collective to apply max right pedal
The sideslip in either case is a very small part - the main element of recovery being the addition of maximum power - this will counter your RoD only in the early or incipient stages of VRS - if you are in full VRS it will just make things worse.
If a proper empirical test was conducted, it is my guess that the best technique for recovery from IVRS is to put the nose forward slightly and pull max power rather than messing around with sideslip. Unless you are going vertically down - normally on approach you will have some forward speed - the quickest way to get airflow over the disc is to move forward faster.
We damaged the Swiss pride, sorry.
Almost 50 years ago I flew with an ETPS (Empire Test Pilot School) graduate in a RN Wasp. He demonstrated fully developed VRS - and I do mean it was really fully developed - we started at 9000ft, commenced the recovery at about 8000ft and recovered at just above 4000ft with the ROD having been pegged to the bottom of the dial. No way can you recover from fully developed VRS within 50 ft!!!!
And as you can see in post #4 the technique isn't even new. Your hero just gave it a name. One wonders, why it did not become the standard technique.
And again from the old timers:
On learning to fly over 50 years ago, we were taught to do VRS recoveries. When the rate of decent was around 4000 to 6000 ft/min we would initiate recovery by lowering collective & pushing stick forward. When the air speed came alive we would pull the stick back & apply power to initiate a climb.
The point was made very strongly that the tail rotor hadn't stalled, only the main rotor, so if the cyclic was too sloppy & wouldn't nose down, we would put in a boot of pedal as all you wanted was airspeed & it didn't matter in which direction you were going. Worked every time!
The point was made very strongly that the tail rotor hadn't stalled, only the main rotor, so if the cyclic was too sloppy & wouldn't nose down, we would put in a boot of pedal as all you wanted was airspeed & it didn't matter in which direction you were going. Worked every time!
Here we have a problem. It would take quite an effort to prove any advantage, since even a slight variation of wind speed, weight or sensitivity of the pilot could tip the balance in one or the other direction. I personally have flown out of an incipient VRS with almost now height loss, just because I caught it in the first moment of sluggishness of the controls. Easy when you know that it is coming. A centimetre of forward stick and you'r out of it. No "lowering collectiv". That's modern helicopters for you. They do not tend to suddenly fall out of the sky with no warning. That is probably the reason, why much more helicopters are bent by SWP (that terrible sudden power loss) than with VRS.
By now we have made a mountain out of a molehill. VRS accidents happen but one has yet to prove that the recovery procedure is the key to prevent them. My completely unproven feeling is, that the recognition of the situation is the problem. "Early enough" as FICH stated. And I go with crab. In an incipient VRS during an approach, stick forward and pull power is the easiest way to save the day. If you want to put in some pedal, be my guest.
Both methods work apparently but this rediscovered technique is harder to learn.
Just a thought, if one is slinging stuff slow and heavy and gets into incipient VRS, pickling the load should solve the problem in a heart beat. Customer might not like you afterwards.
The sideslip in either case is a very small part - the main element of recovery being the addition of maximum power - this will counter your RoD only in the early or incipient stages of VRS - if you are in full VRS it will just make things worse.
No sir. The main element of the VT IS the sideslip, produced due to the bank and the tailrotor thrust. As soon as the blades reach the upwind part of the vortex, the recovery is completed.
The main element is pulling max power - that is what will reduce your rate of descent - the more you tilt the disc and the more you sideslip, the more you tilt your thrust vector away from the vertical which is where it will have most effect on your RoD.
What forward and lateral speed are you presuming in the use of this model? If there is forward momentum it needs to be overcome, which takes time. Is this model for forward speed less than 10 knots? Lateral speed 0 knots, or negligible?
Well, I would not take this picture as the real deal. It is a bit more complicated.
Shawn's book has a more complete picture.
The airflow is in fact highly chaotic - hence the low frequency vibration or waggling of the ship all over the place - and slipping the ship through the vortex on the right ... I doubt that this is the case. I suspect that the vortex disappears before it engulfs the stalled area, since the rotor is now flying through clean air and normal airflow is restored. To have a vortex, one needs a tip of a blade and the point around which the vortex turns is normally beyond the tip, because otherwise the blade would not be able to feed any energy into it.
Others have discussed that, too.
What strikes me here, is the fact, that Tim Tucker would let develop a full VRS, which is not real world and again it is stated, the technique isn't new. For tandem rotor ships it is even the standard technique. SASless should know more about that.
Let's keep that in mind:
It is hard to argue with this. One should keep in mind, that with all these techniques, there is always a week link, and that is the pilot who has to apply the right one in the right circumstances. Adding complexity to the job will not save more bent metal. If the pilot just needs one more second to figure out if it is IVRS or SWP, the whole advantage (if there is one) of the now know as Vuichard Recovery technique is gone.
Frankly, in a non scientific approach that is used in this case, it is becoming more of a dogmatic discussion (who has the biggest).
An interesting read from the antediluvian times.
http://naca.central.cranfield.ac.uk/...rc/rm/3117.pdf
Adding power was the technique then. Or wait until the nose drops. Scary.
Shawn's book has a more complete picture.
The airflow is in fact highly chaotic - hence the low frequency vibration or waggling of the ship all over the place - and slipping the ship through the vortex on the right ... I doubt that this is the case. I suspect that the vortex disappears before it engulfs the stalled area, since the rotor is now flying through clean air and normal airflow is restored. To have a vortex, one needs a tip of a blade and the point around which the vortex turns is normally beyond the tip, because otherwise the blade would not be able to feed any energy into it.
Others have discussed that, too.
What strikes me here, is the fact, that Tim Tucker would let develop a full VRS, which is not real world and again it is stated, the technique isn't new. For tandem rotor ships it is even the standard technique. SASless should know more about that.
Let's keep that in mind:
Another area of concern, pilots sometimes have difficulty recognizing the difference between VRS and settling with power, much less which technique to use under each of those circumstances. Forward cyclic and reduce collective works for both. For the so-called Vuichard Recovery that may not be the case, further analysis is needed.
Frankly, in a non scientific approach that is used in this case, it is becoming more of a dogmatic discussion (who has the biggest).
An interesting read from the antediluvian times.
http://naca.central.cranfield.ac.uk/...rc/rm/3117.pdf
Adding power was the technique then. Or wait until the nose drops. Scary.
If there is forward momentum it needs to be overcome, which takes time.
With the forward escape, you have only the vector from the main rotor. With the sideway escape, you have additionally the tail rotor thrust.
Therefore your escape out of the VRS is faster, and faster means less height loss.
And am talking about a real vortex, in which a solely increase in power only will increase the ROD...
Whether it was a swiss, an american or an african pilot who has developed this technique... I don't care about that.
Fact is, it has a lot of advantages over the nose & collective down method, since you will not be able to do that maneuver in the final approach segment, where the probability of a VRS is the highest.
Why should we teach and learn a method, which will destroy the helicopter?
If the "other" VRS recovery is effectively controlled and reflexively like the introduction of an autorotation, we will be able to prevent a lot of this sad accidents.
Fact is, it has a lot of advantages over the nose & collective down method, since you will not be able to do that maneuver in the final approach segment, where the probability of a VRS is the highest.
Why should we teach and learn a method, which will destroy the helicopter?
If the "other" VRS recovery is effectively controlled and reflexively like the introduction of an autorotation, we will be able to prevent a lot of this sad accidents.
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Mindset
Whichever technique you feel is superior, or available to you in a specific circumstance, one thing remains true;
Understanding that you are entering circumstances which may produce IVRS/SWP/VRS and having a plan to avoid or recover from any of those phenomena is going to produce a massively superior result to blundering along with any technique rattling around the back of your brain waiting to be found, assessed and acted upon.
It seems clear that the technique Mr Vuichard and Mr Tucker have taken the time to write about is a valid one, which can be added to the tools available to pilots open minded enough to understand it's application to their circumstances.
The rest is mental (and keyboard) masturbation.
Carry on......
Understanding that you are entering circumstances which may produce IVRS/SWP/VRS and having a plan to avoid or recover from any of those phenomena is going to produce a massively superior result to blundering along with any technique rattling around the back of your brain waiting to be found, assessed and acted upon.
It seems clear that the technique Mr Vuichard and Mr Tucker have taken the time to write about is a valid one, which can be added to the tools available to pilots open minded enough to understand it's application to their circumstances.
The rest is mental (and keyboard) masturbation.
Carry on......
The initial claims for Vuichard technique were for recovery from fully developed VRS and stated recovery in tens of feet - then it was touted as recovery from IVRS, please make your minds up.
In fully developed VRS you have little control of the main or tail rotor due to the random variations in thrust available at various positions across the disc so trying to utilise sideslip with maximum power applied isn't going to help and will probably deepen the condition.
If we are talking about IVRS - which I think is valid - then application of power is likely to help re-establish the downward flow of air through the rotor without stalling the inboard section (as the RoD isn't high enough).
The sideslip may help or hinder the recovery because you don't know where the worst part of the downwash is - the assumption is that it is ahead and below but that may not be so in a crosswind situation.
Sorry if you think it is keyboard masturbation Freewheel but some of us think that is the height of idiocy to recommend a technique which the inexperienced might view as a 'magic bullet' for VRS recovery - if they believe the technique is so effective they may well not treat the low speed, high RoD environment with as much respect or caution as they should and subsequently get themselves into big trouble.
Pilots must also understand that SWP is not the same as VRS and using the Vuichard technique in this case will make things much worse.
In fully developed VRS you have little control of the main or tail rotor due to the random variations in thrust available at various positions across the disc so trying to utilise sideslip with maximum power applied isn't going to help and will probably deepen the condition.
If we are talking about IVRS - which I think is valid - then application of power is likely to help re-establish the downward flow of air through the rotor without stalling the inboard section (as the RoD isn't high enough).
The sideslip may help or hinder the recovery because you don't know where the worst part of the downwash is - the assumption is that it is ahead and below but that may not be so in a crosswind situation.
Sorry if you think it is keyboard masturbation Freewheel but some of us think that is the height of idiocy to recommend a technique which the inexperienced might view as a 'magic bullet' for VRS recovery - if they believe the technique is so effective they may well not treat the low speed, high RoD environment with as much respect or caution as they should and subsequently get themselves into big trouble.
Pilots must also understand that SWP is not the same as VRS and using the Vuichard technique in this case will make things much worse.
VRS recoveries, option 1
a big dose of 'pole-the F-forward', leave the power on, or apply more to top of yellow & maintain some heading 
~ works a treat; every-time 
Let us all focus our hopes, our dreams, our desires & aspirations to maintaining our airspeed, (translational) for, the loss of which can cause a whole plethora of misgivings
The Vulcan technique does not return airspeed
Happy Happy
VF
~ works a treat; every-time Let us all focus our hopes, our dreams, our desires & aspirations to maintaining our airspeed, (translational) for, the loss of which can cause a whole plethora of misgivings
The Vulcan technique does not return airspeed
Happy Happy
VF
I fully agree with you, that the target number one is to avoid the vrs.
A student has to learn the causes and the initial signs before **** gets real.
But he has also to learn to handle the real ****...
Concerning IVRS or VRS, can you tell me according your judgement where the transition between these two things is?
For example, i fly the helicopter into vrs. Random yaw, vibrations etc. I don't do anything. Sinkrate begins to increase. I don't do anything. At 1000ft/min, i apply power. Sinkrate increases more. Is that IVRS or full developed VRS?
Only that we speak about the same...
A student has to learn the causes and the initial signs before **** gets real.
But he has also to learn to handle the real ****...
Concerning IVRS or VRS, can you tell me according your judgement where the transition between these two things is?
For example, i fly the helicopter into vrs. Random yaw, vibrations etc. I don't do anything. Sinkrate begins to increase. I don't do anything. At 1000ft/min, i apply power. Sinkrate increases more. Is that IVRS or full developed VRS?
Only that we speak about the same...
Last edited by FICH; 18th Feb 2016 at 07:05.