tail rotor failure at hover
SASless Question being....if a full right pedal application equals or exceeds the Turning Moment of the Main Rotor system....one could test various techniques to control the spinning of the aircraft.
If it's 0° or even negative, I'd say full right pedal would result in zero "counter thrust",
e.g. same "counter torque" as if tail rotor fell off.
Flying bull,
If you are in the low hover, you should not just dump the lever. Chop the throttle and cushion with remaining lever.
If you are in the high hover, then yes, dump lever AND chop throttle. Then endeavour to get forward airspeed. Unless you are very quick here, then it's curtains; irrecoverable unless you are quick.
If you are in the low hover, you should not just dump the lever. Chop the throttle and cushion with remaining lever.
If you are in the high hover, then yes, dump lever AND chop throttle. Then endeavour to get forward airspeed. Unless you are very quick here, then it's curtains; irrecoverable unless you are quick.
Flying bull,
If you are in the low hover, you should not just dump the lever. Chop the throttle and cushion with remaining lever.
If you are in the high hover, then yes, dump lever AND chop throttle. Then endeavour to get forward airspeed. Unless you are very quick here, then it's curtains; irrecoverable unless you are quick.
If you are in the low hover, you should not just dump the lever. Chop the throttle and cushion with remaining lever.
If you are in the high hover, then yes, dump lever AND chop throttle. Then endeavour to get forward airspeed. Unless you are very quick here, then it's curtains; irrecoverable unless you are quick.
Im with Flying Bull.
If you're sitting in a type with twist throttles on the collective, and you can react and cut all engines within 0,5s: then do it in the same time as you dump the collective.
Otherwise, dump collective as Flying bull said, or crash.
Never experienced this live, but a lot in Full Flight Sims, different types. All Sims teach the same = if you dont react quick, the rotation speed will be very high very soon.
if you dont react quick, the rotation speed will be very high very soon.
At first, I thought the guy flying was making a right hand pedal turn to look for a parking place....as the rotation was quite mild as the Tail Rotor wound down. The first full revolution as we passed what I considered our entry point heading was not too bad but was gaining in rate. As we went by the second time...the rate was very significant and noticeably increasing at a faster rate than the on the first trip around the mast. I had now tweaked to it being a for real problem and not the doing of the Dunderhead who was driving.
As I was a passenger and not part of the crew I was deferring to his Duty Status but began to suggest a course of action....by clearly stating over the Intercom..."Chop the Throttle!".
He did not...and we started around yet another time and on the third time past the starting point....things were becoming a blur...and my suggestion to chop the Throttle was now an emphatic plea!
As we went around on the fourth rotation...my Aviator Ray Bans were leaving my face propelled by my bulging eyeballs...and I elected to take matters into my own hands and chopped the throttle myself.
We were still rotating but at a much reduced and slowing rate...things were coming into focus again...and eyeballs were returning to what seemed a normal position.
I suppose I could have helped with the Collective Pull but then he was signed for the aircraft and was at the controls and one would think he would just instinctively do what was necessary at this point. I was wrong...he did not...and the Skids nicely cushioned our Landing and at the same time made it much easier to get out of the Cockpit as there was no need to climb down but rather to step up just a short bit.
I thanked him for the Ride....and lied when I said I would look forward to a return flight with him in a few Days.
Long story....but should help to describe how quickly things happen when the Tail Rotor decides to take a Holiday.
Getting the power off is the key. Get that right and the rest is pretty much an after thought. Don't and you are in for the ride of you Life that even Disneyworld cannot beat.
Hi Marly Lite,
as AAKEE says, if you donīt dump the collective immediately, you get a very high rate of rotation, which increases the risk of being killed.
You have to condition yourself to accept a hard landing in case of hoverfailures in favour of surviving.
The tendency of pilots is to try to control the bird - which leads to desaster.
I actually know a pilot, who got a big reinforced plastic bag into his fenestron - and he said, his simulatortraining - putting the bird instantly down - saved his day.
Christoph 13 nach Zwischenfall nicht mehr flugfähig (2x ergänzt) | rth.info - Faszination Luftrettung | Rettungshubschrauber online
Surf the internet and see, what happens, if pilots try to cope with tail rotor problems...
should have accepted the fate of being in the water - but you can see, how fast the spinng starts...
and that french army puma could still be flying, when the pilot would have accepted a hard landing - instead....
So I wonīt spend any time in trying to kill an engine - before being on the ground.
Rather have some bend skids/wheels and walk away - as you know, every landing, you can walk away from is a good landing...
every landing, you still can use the aircraft - is a very good landing
as AAKEE says, if you donīt dump the collective immediately, you get a very high rate of rotation, which increases the risk of being killed.
You have to condition yourself to accept a hard landing in case of hoverfailures in favour of surviving.
The tendency of pilots is to try to control the bird - which leads to desaster.
I actually know a pilot, who got a big reinforced plastic bag into his fenestron - and he said, his simulatortraining - putting the bird instantly down - saved his day.
Christoph 13 nach Zwischenfall nicht mehr flugfähig (2x ergänzt) | rth.info - Faszination Luftrettung | Rettungshubschrauber online
Surf the internet and see, what happens, if pilots try to cope with tail rotor problems...
should have accepted the fate of being in the water - but you can see, how fast the spinng starts...
and that french army puma could still be flying, when the pilot would have accepted a hard landing - instead....
So I wonīt spend any time in trying to kill an engine - before being on the ground.
Rather have some bend skids/wheels and walk away - as you know, every landing, you can walk away from is a good landing...
every landing, you still can use the aircraft - is a very good landing
In (almost) any machine with overhead speed selects or a fuel control away from the collective grip you must dump the collective as soon as you identify the problem. There is no time to faff around letting go of the collective to wind back the engine(s).
That covers most types, and those with a collective twist-grip throttle would still find you dithering around whilst the rotation builds up. Lower the lever and accept the machine will still be building up a head of rotational steam on the way down.
Been there, done that, in a BK117 where I stuffed the tail into a tree at night in a high (20-30ft) hover. Collapsed the skids but only turned about 120 degrees in all: if I'd hesitated before dumping the lever it may have been far, far worse.
That covers most types, and those with a collective twist-grip throttle would still find you dithering around whilst the rotation builds up. Lower the lever and accept the machine will still be building up a head of rotational steam on the way down.
Been there, done that, in a BK117 where I stuffed the tail into a tree at night in a high (20-30ft) hover. Collapsed the skids but only turned about 120 degrees in all: if I'd hesitated before dumping the lever it may have been far, far worse.
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I agree with FB and JE.
The most appropriate immediate actions really have to be type specific (which is why I replied to SAS's post by saying that were were too many variables to give a "one size fits all" answer).
The favourite saying of some is "lucky left, rotten right" when it comes to TR failures / malfunctions. That only works if you fly "American Rotation" rotor bladed aircraft.
It's more accurate to say that the "lucky" side is the retreating blade side.
The most appropriate immediate actions really have to be type specific (which is why I replied to SAS's post by saying that were were too many variables to give a "one size fits all" answer).
The favourite saying of some is "lucky left, rotten right" when it comes to TR failures / malfunctions. That only works if you fly "American Rotation" rotor bladed aircraft.
It's more accurate to say that the "lucky" side is the retreating blade side.
ST and JE,
I'll happily agree with you for single pilot operation with awkward speed selects in the roof etc. And sure, twin pilot requires a switched on P2!
Certainly for twist grip I maintain that you are better off chopping the throttle. SASLESS's example explains why. Unfortunately in his case the driver forgot the 'cushion' part!
FB
FB, IF you close the throttle, the rate rotation stops accelerating, and starts to slow. Only now, you still have the ability to cushion.
I'll happily agree with you for single pilot operation with awkward speed selects in the roof etc. And sure, twin pilot requires a switched on P2!
Certainly for twist grip I maintain that you are better off chopping the throttle. SASLESS's example explains why. Unfortunately in his case the driver forgot the 'cushion' part!
FB
says, if you donīt dump the collective immediately, you get a very high rate of rotation, which increases the risk of being killed.
As someone who actually has had a complete loss-of-thrust t/r failure at an IGE hover in a Bell 206 I can speak to this issue from a practical standpoint not theoretical. Once the anti-torque is gone, the yaw rate builds up blindingly fast.
First, get rid of the torque if you can. In my case I chopped the throttle. After that it's just a hovering auto. If the throttle/FCL is not on the collective, then yes, dump the lever and fast. Recognize it early and get the landing gear on the ground before the rate of rotation gets too high. Do not wait.
First, get rid of the torque if you can. In my case I chopped the throttle. After that it's just a hovering auto. If the throttle/FCL is not on the collective, then yes, dump the lever and fast. Recognize it early and get the landing gear on the ground before the rate of rotation gets too high. Do not wait.
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During my time as a simulator instructor we were tasked by Boscombe Down to experiment with tail rotor malfunctions
Sorry to say this-but this is where a lot of "false advise" comes from, as the simulator only simulates whatever someone programmed into it (usually based on facts and data fed from live aircraft, but-in case of emergency procedures-mainly from "pilot tells" stories)..
To simulate the effects of a tail rotor failure, someone would have to hook up computers to a helicopter in flight EXPERIENCING a tail rotor failure.....
Even then, this data can only be used for this specific model (although general procedures might result out of it).
For many years, pilots were told that one is able to "fly away even with a separated tail rotor", as long as one has enough airspeed.....this is slowly changing now due to studies carried out like the one in the UK....
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Sorry to say this-but this is where a lot of "false advise" comes from, as the simulator only simulates whatever someone programmed into it (usually based on facts and data fed from live aircraft, but-in case of emergency procedures-mainly from "pilot tells" stories)..
Did you not read the rest of my post? Especially this paragraph:
Until that time the only tail rotor "failure" covered in the FRC checklist was drive shaft failiure. We flew many different scenarios in the sim which enabled us to provide guidance on other types of failures. We were careful not to give actual drills to follow by rote because correct diagnosis of the actual type of malfunction was critical and we were "flying" a simulator, not the real aircraft and the response of the sim may not have been exactly as per the real airframe.
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No, i read the whole thing....sorry, i should have made that more clear...
I was intending to issue a warning to all pilots thinking that-because they handled things well in a simulator, they now know everything about what's happening in the real aircraft......and thatīs not the case...
I was intending to issue a warning to all pilots thinking that-because they handled things well in a simulator, they now know everything about what's happening in the real aircraft......and thatīs not the case...
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HueyRacer, that was the advice we gave. It was meant as guidance and food for thought. It was never meant to be a complete answer but it later proved far better than that previously taught, or rather, what had been previously glossed over, by the UK military and civilian training organisations alike. At least, three Puma pilots who subsequently suffered tail rotor malfunctions for real said so.
The CAA paper which I provided a link to in my earlier post shows that the conclusions of the later trials team were very similar to what we had found some years previously and passed on to Puma pilots during their sim. training with us. The TRCF incident I referred to is incident #27 in that document. Pages 151/152 gave further information on the training we provided.
The CAA paper which I provided a link to in my earlier post shows that the conclusions of the later trials team were very similar to what we had found some years previously and passed on to Puma pilots during their sim. training with us. The TRCF incident I referred to is incident #27 in that document. Pages 151/152 gave further information on the training we provided.
Not had one go in the hover,but about 50-60 knots in formation climb;whole tail-rotor and gearbox departed,about 90 deg yaw,and the stick on the back stop,as the C of G was now over the nose as well.Entered auto,then chopped the engine and eol`d into a clearing.Aircraft was lifted out by Belvedere,bits of t/r were found,caused by a fatigue crack in the t/r blade spindle.New g/box and t/r replaced,aircraft flew again a couple of weeks later.
Few pics in `Rotorheads around...cockpit views(not video),p15...
A couple of days later an American Flight Safety magazine turned up with an article about`How to handle a tail-rotor failure`.....
Few pics in `Rotorheads around...cockpit views(not video),p15...
A couple of days later an American Flight Safety magazine turned up with an article about`How to handle a tail-rotor failure`.....
Folks used to look at me cross-eyed when I announced my preference for an aircraft that had its CG at the rear limit. I asked them what it would feel like to have a very forward most CG location and experience what you did.
The venerable old Huey had some teething pains early on when the D and H models were coming into service.
It started with entire Tailbones leaving the attach point on the Fuselage....moved back to the 42 Degree Gearbox attach points....then to the 90 Degree Gearbox attach points....and in time after more than a few Tail Rotors got shucked.....the Bell Engineers got it all sorted out.
Fort Rucker had two Tail Boom separations in a single day....it was that bad.
The venerable old Huey had some teething pains early on when the D and H models were coming into service.
It started with entire Tailbones leaving the attach point on the Fuselage....moved back to the 42 Degree Gearbox attach points....then to the 90 Degree Gearbox attach points....and in time after more than a few Tail Rotors got shucked.....the Bell Engineers got it all sorted out.
Fort Rucker had two Tail Boom separations in a single day....it was that bad.
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FH1100 Pilot says:
Well, I've never had LTE or a TR failure, so take this with a grain of salt, but:
When I was first instructing, we had another CFI who had an LTE on top of a mountain and crashed the R22 he was flying. A few weeks later I flew with him and he demonstrated a very fast rotation (still probably not as fast as if you have a TR failure but still pretty damn fast). He pointed out that if you don't try to look at individual items out the windshield, but instead treat the trees/houses/whatever as a blur representing the horizon, you can at least maintain a level attitude for a short time.
I find that most people who have never seen this demonstrated tend to drop a wing or the nose and start doing a pirouette, the danger being that not only are you spinning, you are now starting to translate so you are even more likely to tip the machine over upon landing.
Oh, and someone mentioned LTE vs TR failure. My feeling is that if torque is spinning me, I don't have time to diagnose the cause. I'm gonna get rid of the torque and put it down and we can figure that stuff out later. Not sure why LTE would be any less serious than a mechanical failure. (Yeah, maybe you could have prevented it, but once it happens seems like it's just as deadly). Not sure whether you'll get the same rotation rates out of LTE vs TR fail. Hoping not to find out!
We practice this stuff, but I have no illusions that a real life TR failure will be as benign as when we practice.
I have to say, though, that I have a strong preference for machines with throttle(s) on the collective because of this.
As someone who actually has had a complete loss-of-thrust t/r failure at an IGE hover in a Bell 206 I can speak to this issue from a practical standpoint not theoretical. Once the anti-torque is gone, the yaw rate builds up blindingly fast.
When I was first instructing, we had another CFI who had an LTE on top of a mountain and crashed the R22 he was flying. A few weeks later I flew with him and he demonstrated a very fast rotation (still probably not as fast as if you have a TR failure but still pretty damn fast). He pointed out that if you don't try to look at individual items out the windshield, but instead treat the trees/houses/whatever as a blur representing the horizon, you can at least maintain a level attitude for a short time.
I find that most people who have never seen this demonstrated tend to drop a wing or the nose and start doing a pirouette, the danger being that not only are you spinning, you are now starting to translate so you are even more likely to tip the machine over upon landing.
Oh, and someone mentioned LTE vs TR failure. My feeling is that if torque is spinning me, I don't have time to diagnose the cause. I'm gonna get rid of the torque and put it down and we can figure that stuff out later. Not sure why LTE would be any less serious than a mechanical failure. (Yeah, maybe you could have prevented it, but once it happens seems like it's just as deadly). Not sure whether you'll get the same rotation rates out of LTE vs TR fail. Hoping not to find out!
We practice this stuff, but I have no illusions that a real life TR failure will be as benign as when we practice.
I have to say, though, that I have a strong preference for machines with throttle(s) on the collective because of this.
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P C
Well for one thing, LTE is temporary. Lowering the lever and nose should lead to recovery (if you have enough height that is).
Not sure why LTE would be any less serious than a mechanical failure.
For the Hover TR Failure we have been teaching "DON'T DUMPT THE LEVER". Accept the rotation, keep level disc attitude and slowly lower to the surface allowing the wheels/skids to generate friction to slow the rotation. Dumping the lever with a rapid yaw rate we think will cause the wheels/skids to dig in an lead to a roll over crash.
How are other instructors teaching this failure?
I am now wondering how the Hover technique we are peddling above would translate to what is effectively at TDP, a zero speed hover?[/COLOR]
If I'd made contact with a higher rate of rotation then a roll over would have been almost guaranteed.
Apologies for the thread drift.
Throttles in the roof - during one sim session in a 76 level D we were taught, if single pilot (we always were), a tail drive failure in the hover could be handled, if power available, by climbing vertically to height (1,000 suggested), nosing over to gain airspeed, accept side slip, and fly to suitable, spot for auto. It worked in the sim, but in real life? Always had my doubts having seen a fully loaded Huey lose drive in the hover. First question is sim modelling accuracy. John Dixon might give his considered opinion.
Helicopter flying is not inherently dangerous, it's only as dangerous as you want to make it. Three decades with an offshore operator and they never had an accident, nor injured anyone.
Helicopter flying is not inherently dangerous, it's only as dangerous as you want to make it. Three decades with an offshore operator and they never had an accident, nor injured anyone.