A different take on Vuichard
Exactly, when doing buckets on a 100’ line into the dip sites on cloudy days, you are on the edge of it all the way in the latter portions of the approach. I need pilots to recognize the incipient nature and make a cyclic adjustment without losing more than 20’ of altitude. It can be done, we sit right on the edge in training and go in and out of the start of it multiple times on one training event.
what increasing power does though, I assume, is increase your torque and consequently tail rotor pitch, and therefore your lateral slip stream.
Even if you main rotor is stalled and cyclic controlability degraded, the tail rotor is perfectly fine to help you step out of the VRS. I thought that was the whole principle of the Vuishard recovery.
what increasing power does though, I assume, is increase your torque and consequently tail rotor pitch
Vuichard's technique relies on cross controlling to sideslip out of the vortex - you need cyclic and yaw inputs since a yaw input alone will just turn the nose.
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"I am very concerned about the dramatic increase in helicopter accidents in Europe in recent weeks.
We must learn from this that unfortunately we cannot improve the skills of pilots and flight instructors through administrative processes in one way or another.
The current over-regulation in Europe ultimately leads to the opposite. We cannot improve the skills of pilots and in any way through thousands of pages of operations and training manuals, audits, quality systems and checks.
The solution to rapidly reducing these accidents can only be achieved through efficient, evidence-based training in modern simulators."
We must learn from this that unfortunately we cannot improve the skills of pilots and flight instructors through administrative processes in one way or another.
The current over-regulation in Europe ultimately leads to the opposite. We cannot improve the skills of pilots and in any way through thousands of pages of operations and training manuals, audits, quality systems and checks.
The solution to rapidly reducing these accidents can only be achieved through efficient, evidence-based training in modern simulators."
Apparently simulators are the only hope at preventing accidents?
'without all that paperwork, regulations, inspections, etc....how does one think the Jobsworths at mulitiple levels of government can earn a living then retire with a nice pension?
Perhaps they could stop using low time, hours building instructors who are little better than the students themselves.
But that would mean paying more...........
But that would mean paying more...........
Originally Posted by [email protected]
Perhaps they could stop using low time, hours building instructors who are little better than the students themselves.
But that would mean paying more...........
But that would mean paying more...........
Not quite. That may be A solution. It certainly isn’t THE solution.
There is some great work on helicopter flight simulation in Northern Switzerland, which is a long way forward of old procedure trainers or pretty crappy FNPTs. Modern software such as X-Plane, the rapid development of VR and even “affordable” full motion devices to put steering hardware onto, does indeed mean that a significant portion of flight training will surely be done on such devices in the future. Perhaps Vichaurd is making the case for getting his technique embedded into the syllabus? That would fit his suggested revisions for avoiding all VRS events as per the website:
- From the beginning, train only "Vuichard Recovery" during the first few hours of PPL until it becomes a reflex when feeling a low-G at low speed
- Equip all helicopters with a string (woolometer) to have a clear, visible and correct flow indication
- Equip all helicopters with an IVSI
- Train downwind approaches with special emphasis on a max. rate of descend <300ft/min
- Review the procedure during all check flights
- All civil aviation authorities should amend the FTO’s training manuals
- All helicopter manufacturers should publish safety notice
- All simulator manufacturers should review simulator behavior in VRS
- Forbid all backward CAT A procedures in the AFM/POH
- Amend asap the FAR&CS 27 and 29: manufacturers should provide data showing the rate of descent to enter in VRS in function of weight, altitude and temperature
- Never use the autopilot in Auto Hover mode outside of flat areas, if the reference is taken from the radar altimeter
Perhaps more concerning is that VRS is a beast that is hard to quantify and that begs the question of how reliably the behaviour of the helicopter can be simulated. Let’s hope that the tail won’t be wagging the dog when it comes to programming X-Plane and similar engines to accommodate the new gold-standard recovery method that Monsieur Vichaurd would like to promote.
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I have said this before but here goes again. My only time in true VRS occurred at 2000 ft AGL. Student had done 6 very nice recoveries from IVRS. We had one last go. Down wind pulling 18MAP in a Hughes 300. Airspeed has gone below 30 kts, GPS ground speed about 8. IVSI showing 700 ft a min airspeed indicator now less than 20 knots. Ac has already gone through the Hughes rumble ( loss of translational lift ) . I ask the student to recover, to my surprise he pulls full collective, almost instantly the ac pitches about 75 degrees up, no movement on the cylic. I glance at the IVSI which now is rapidly going south of 1500 fpm. I apply full left pedal and full forward cylic, NOTHING happens apart from my ring piece puckering. In desperation I dump the collective and push full right pedal. Now then ac is pitched what feels like 90 degrees nose down with ASI rapidly accelerating towards VNE. At this point the ground is worryingly close, gingerly apply rear cylic and a load of collective to stop the disc overspeeding. Pull the ac out just above tree top height. Back to airfield to change underwear . This is why I think Claude has never experienced VRS. Now i do a bit of line work ( about 1500 hours so not that experienced compared to a lot ) only problem with stepping left or right is a load of shouting from the ground crew as one swings the load into them ! I have always found it better to push forward but always willing to learn.
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Curious now,...does Vuichard distinguish between VRS and IVRS? I only ask because this distinction is something I've only come across here on pprune. I mean, its been a while since I opened the text, but I don't remember the Rotorcraft Flying Handbook making it either? 
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IMO, the Vuichard technique has merits, but it is an advanced manuevre that would waste a student's time learning during a PPL course. They need to know the signs of onset of VRS and how to prevent it from occuring, and the basic recovery method.
It is similar to doing 0 airspeed, or reverse autorotations. Yes, it can be done, but really, most of the time it is instructors showing off their skills.
It is similar to doing 0 airspeed, or reverse autorotations. Yes, it can be done, but really, most of the time it is instructors showing off their skills.
I have said this before but here goes again. My only time in true VRS occurred at 2000 ft AGL. Student had done 6 very nice recoveries from IVRS. We had one last go. Down wind pulling 18MAP in a Hughes 300. Airspeed has gone below 30 kts, GPS ground speed about 8. IVSI showing 700 ft a min airspeed indicator now less than 20 knots. Ac has already gone through the Hughes rumble ( loss of translational lift ) . I ask the student to recover, to my surprise he pulls full collective, almost instantly the ac pitches about 75 degrees up, no movement on the cylic. I glance at the IVSI which now is rapidly going south of 1500 fpm. I apply full left pedal and full forward cylic, NOTHING happens apart from my ring piece puckering. In desperation I dump the collective and push full right pedal. Now then ac is pitched what feels like 90 degrees nose down with ASI rapidly accelerating towards VNE. At this point the ground is worryingly close, gingerly apply rear cylic and a load of collective to stop the disc overspeeding. Pull the ac out just above tree top height. Back to airfield to change underwear . This is why I think Claude has never experienced VRS. Now i do a bit of line work ( about 1500 hours so not that experienced compared to a lot ) only problem with stepping left or right is a load of shouting from the ground crew as one swings the load into them ! I have always found it better to push forward but always willing to learn.
Its easier to demonstrate IVRS when downwind as you have to lose ETL. If you try demonstrating it into a 20 kt headwind you have to be moving backwards over the ground at 20 kts, which feels a little odd, and in reality most PPL holders are going to get into IVRS at altitude when they are downwind (eg circling someones house slowly to take a photo)
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Exactly.
And given FI pay is stuck at 2007 levels....
And given FI pay is stuck at 2007 levels....
Originally Posted by [email protected]
Perhaps they could stop using low time, hours building instructors who are little better than the students themselves.
But that would mean paying more...........
But that would mean paying more...........
I will probably get a lot of flak for this but this is a combination of 2 posts on the old discussion.
I am posting a couple of photos just to relieve the monotony.
I was doing a job which entailed a lot of climbing, descending and hovering at high altitudes AGL.
I discovered that it is possible to enter VRS from a steady hover.
It was a great surprise the first time.
Due to the job it happened a lot. So I got the chance to try various things out.
Maintaining a vertical descent pulling power just increased the rate of descent.
Controls got sloppy but the aircraft did not enter any unusual attitudes.
There were no torque or RPM fluctuations.
Recovery was simple, Initiate forward or sideways movement and exit the column of descending air.
The aircraft was very light during these operations just myself and sometimes 1 passenger and around half fuel.
It warned you it was going to enter VRS. You would be happily sitting there at about 80%Q. The VSI would flicker (not even to 100FPM down) Altimeter would hardly move. If you did nothing it would enter VRS shortly thereafter. Pull a bit of collective and it usually entered VRS immediately and fully.
It only happened in calm wind conditions.
As we were hovering, climbing or descending on a ‘Laser’ beam you were never moving more than 2 feet in the horizontal from ground level to as much as 7000 AGL. Usually we only climbed 2000-4000 ft.
If you lost the ‘Laser’ beam you had to descend to ground level in order to reacquire it so sometimes I remained in VRS to descend.
The aircraft was being observed using a 50x theodolite so the surveyors could see the aircraft depart downwards. They would have me in the crosshairs as I hovered and suddenly I would depart downwards. They thought it was very funny to watch.
Just for info the aircraft had a cowling just abut under the fwd seats. The cowling had a screen on the bottom. Inside the cowilng was a video camera focused on the screen and a small 3 inch square monitor was installed on the instrument panel. A 10 amp gyro stabilized ‘Laser’ was placed on the ground pointed vertically upwards. You hovered low over the ‘Laser’ and placed the aircraft over it until you saw the ‘laser’ dot on the screen. You then initiated a climb at about 6-800 FPM keeping the dot as close to the center of the screen as possible. If you rapid control movements failed in this and you lost the dot you had to return to ground level and start over again. It took a lot of practice to learn the technique usually about 5 -10 hours. Some guys caught on quickly, some never could. The customer paid fro the training. They also allowed you to go out and practice if you didn’t do a shot for a day or two as it was a skill that required constant practice. Totally an eye, hands, feet coordination thing…if you had to think about it the dot was gone.
Starting from 100 ASL to 8000 ASL Temps -20 to +25C. Terrain100 ASL to 1500-2000.
Well some folks are going to say that entering VRS in still air and zero rate of descent is impossible.
In discussion years later with a very experienced and well respected test pilot he was surprised to hear of it but thought that it was just amazing that the circumstance was created. The ‘Laser’ keeping the aircraft in a +- 24 inch hover for extended periods and the aircraft being tracked with a theodolite. The chance to operate in the conditions described and stay in VRS for up to 1-2 minutes try various things and observe results was a unique opportunity. He said that they had never even thought of doing it and it would have been a separate test programme during which it would have been difficult to achieve the test parameters.. I agreed totally with him. It was an interesting thing but not worth the candle to spend time to explore. In the end what would have been the benefit of it a except the “Been There Done That” T-shirt.
You always lost the ‘Laser’ dot when it happened so you had to descend back down to ground level so staying in VRS was quick way to get there. I found exiting at a +-45 degree from aircraft heading with a +- 10 degree nose down attitude to gain fwd speed seemed to work best. You could exit by entering autorotation but this involved a considerable height loss. Exiting fully developed VRS with power applied and fwd speed was the most easy but when you are looking at VS anywhere from -1500 to -2500 it is going to take TIME and ALTITUDE to return to straight and level flight. As I stated before aside from the sloppy controls the aircraft never entered any unusual attitude or did anything scary. It seemed happy in the state it was in, no RPM, Torque or heading changes.
DLY a nice 350D. The Helicopter was brought to the hover over the laser with the beam hitting the screen on the cowling.
The dot is displayed on the small TV screen on the right,
The 10 amp gyro stabilized laser in position. Now just keep the dot in the screen and climb vertically 4-5 thousand feet and come to a stable hover for the surveyors to take the shot. .
I am posting a couple of photos just to relieve the monotony.
I was doing a job which entailed a lot of climbing, descending and hovering at high altitudes AGL.
I discovered that it is possible to enter VRS from a steady hover.
It was a great surprise the first time.
Due to the job it happened a lot. So I got the chance to try various things out.
Maintaining a vertical descent pulling power just increased the rate of descent.
Controls got sloppy but the aircraft did not enter any unusual attitudes.
There were no torque or RPM fluctuations.
Recovery was simple, Initiate forward or sideways movement and exit the column of descending air.
The aircraft was very light during these operations just myself and sometimes 1 passenger and around half fuel.
It warned you it was going to enter VRS. You would be happily sitting there at about 80%Q. The VSI would flicker (not even to 100FPM down) Altimeter would hardly move. If you did nothing it would enter VRS shortly thereafter. Pull a bit of collective and it usually entered VRS immediately and fully.
It only happened in calm wind conditions.
As we were hovering, climbing or descending on a ‘Laser’ beam you were never moving more than 2 feet in the horizontal from ground level to as much as 7000 AGL. Usually we only climbed 2000-4000 ft.
If you lost the ‘Laser’ beam you had to descend to ground level in order to reacquire it so sometimes I remained in VRS to descend.
The aircraft was being observed using a 50x theodolite so the surveyors could see the aircraft depart downwards. They would have me in the crosshairs as I hovered and suddenly I would depart downwards. They thought it was very funny to watch.
Just for info the aircraft had a cowling just abut under the fwd seats. The cowling had a screen on the bottom. Inside the cowilng was a video camera focused on the screen and a small 3 inch square monitor was installed on the instrument panel. A 10 amp gyro stabilized ‘Laser’ was placed on the ground pointed vertically upwards. You hovered low over the ‘Laser’ and placed the aircraft over it until you saw the ‘laser’ dot on the screen. You then initiated a climb at about 6-800 FPM keeping the dot as close to the center of the screen as possible. If you rapid control movements failed in this and you lost the dot you had to return to ground level and start over again. It took a lot of practice to learn the technique usually about 5 -10 hours. Some guys caught on quickly, some never could. The customer paid fro the training. They also allowed you to go out and practice if you didn’t do a shot for a day or two as it was a skill that required constant practice. Totally an eye, hands, feet coordination thing…if you had to think about it the dot was gone.
Starting from 100 ASL to 8000 ASL Temps -20 to +25C. Terrain100 ASL to 1500-2000.
Well some folks are going to say that entering VRS in still air and zero rate of descent is impossible.
In discussion years later with a very experienced and well respected test pilot he was surprised to hear of it but thought that it was just amazing that the circumstance was created. The ‘Laser’ keeping the aircraft in a +- 24 inch hover for extended periods and the aircraft being tracked with a theodolite. The chance to operate in the conditions described and stay in VRS for up to 1-2 minutes try various things and observe results was a unique opportunity. He said that they had never even thought of doing it and it would have been a separate test programme during which it would have been difficult to achieve the test parameters.. I agreed totally with him. It was an interesting thing but not worth the candle to spend time to explore. In the end what would have been the benefit of it a except the “Been There Done That” T-shirt.
You always lost the ‘Laser’ dot when it happened so you had to descend back down to ground level so staying in VRS was quick way to get there. I found exiting at a +-45 degree from aircraft heading with a +- 10 degree nose down attitude to gain fwd speed seemed to work best. You could exit by entering autorotation but this involved a considerable height loss. Exiting fully developed VRS with power applied and fwd speed was the most easy but when you are looking at VS anywhere from -1500 to -2500 it is going to take TIME and ALTITUDE to return to straight and level flight. As I stated before aside from the sloppy controls the aircraft never entered any unusual attitude or did anything scary. It seemed happy in the state it was in, no RPM, Torque or heading changes.
DLY a nice 350D. The Helicopter was brought to the hover over the laser with the beam hitting the screen on the cowling.
The dot is displayed on the small TV screen on the right,
The 10 amp gyro stabilized laser in position. Now just keep the dot in the screen and climb vertically 4-5 thousand feet and come to a stable hover for the surveyors to take the shot. .
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If you need more QHIs and the system is too slow to produce them (and you are bleeding experience as people jump ship) then the idea of a creamie becomes more attractive.
For those that don't know the term it comes from the FJ world where the best students on the course were 'creamed off' to become instructors without any operational experience. Much like low time PPLs hour building via the AFI route.