Japanese AW139 down

[CharlieOneSix]

Japanese Police AW139 crashed whilst transporting a heart for transplant. Looks like something in the drive to the tail rotor let go. Seven on board. Well handled for all of them to walk away bar one serious injury.

English news report

[Boac]

Interested to understand how you 'land' with TRF. With that rate of descent I guess you would have to whack in 'N' (where 'N' is a large number - assuming you have any Nr left...) collective at exactly the right moment, in which case you would rotate rather rapidly?

[PHXPhlyer]

Could some of our whirley bird drivers comment on technique for TRF, please?

PP

[CharlieOneSix]

In some circumstances it is possible to find an airspeed at which you can continue in unbalanced but stable flight. However the moment you slow from that airspeed to land the torque reaction will spin the fuselage - so you will probably land fast and roll. Not a good solution usually.

In this case the fuselage is spinning. There is no choice - stopcock both engines to get rid of the torque reaction. If height permits now try and get some airflow past the fuselage to slow the rotation. Establish autorotation. The only torque reaction now is friction within the main gearbox. Hopefully when you pull collective to land the rotation will be minimal but you will probably roll as this chap did. He managed to get the undercarriage down which was a good effort!

There was a Super Puma in our company which literally lost its tail rotor and tail rotor gearbox over the North Sea due to a lightning strike which detached them. He now had a CofG problem - long moment arm - and he stopcocked both engines and ditched and everyone got out. It was the subject of a Discovery TV documentary some years back.

As an aside, the co-pilot also flew gliders and later had to bail out over the Grampians when his elevator control became detached.......

G-TIGK accident

56C.JPG (45.4 KiB) Viewed 444 times

[PHXPhlyer]

C16:
Thanks,

PP

Whirley birds and airships still on my list.
Just have to find that winning lottery ticket!

[Boac]

I cannot begin to understand how any pilot can get that right enough to walk away. It is not as if it is like a normal 'engine-off' auto-rotation that can be practised.

Skill indeed.

[TheGreenGoblin]

I cannot begin to understand how any pilot can get that right enough to walk away. It is not as if it is like a normal 'engine-off' auto-rotation that can be practised.

Skill indeed.

His Kung Fu was truly strong Johnny...

Preternatural skill ... like this chap...

[Seenenough]

I cannot begin to understand how any pilot can get that right enough to walk away. It is not as if it is like a normal 'engine-off' auto-rotation that can be practised.

Skill indeed.

It is quite simple Bo-We spend many training hours being taught how to do emergency landings without tail rotor authority which can occur because a drive link has broken and the rotor is not turning or the rotor is turning but but a control link has failed or something has prevented the pedals from moving.

The nose of the helicopter can be moved either way by raising and lowering the collective and also by using the throttle especially in the case of a piston engined helicopter.

[Boac]

Thanks - not something that was covered on my heli course. Glad it is simple.

Out of interest, how is the yaw simulated?

[CharlieOneSix]

It is quite simple Bo....

Says an optimist!

As far as simulating landings with jammed tail rotor pedals is concerned, on the actual helicopter the instructor/examiner holds the pedals in a fixed position and the student/examinee takes his feet off the pedals. In general by carrying out a crabbing approach with the wind on the right - American designs, opposite for French and Russian - you judge that as you apply collective to cushion the landing the nose of the helicopter swings to the runway direction as the wheels touch. You can get the touchdown speed quite low. We used to practice that on our 6 monthly check rides.

It is impossible to practice loss of tail rotor drive in the helicopter. I've done it in S76 and S61 simulators but I didn't think it was that convincing. You hopefully never have to compare the real thing to the simulator! The simulator is a best guess at what might happen.

With the Bell 214ST, even though it was a twin turbine helicopter, both throttles were on the collective, not in the roof panel. With a jammed pedals approach you could wind one throttle back a few percent so it is out of the governed range and use the other throttle to play with the nose direction of the helicopter much as seenenough proposes with a piston engine helicopter. You are effectively playing with the torque reaction. With helicopters such as the S76 and S61 which have the throttles in the roof panel that option isn't really available unless you have a really in tune co-pilot!

Back in 1984 we had a real tail rotor control disconnect incident with one of our Bell 222 helicopters on our Metropolitan Police contract. This was due to a fatigue fracture in the control run. The pilot had carried out this emergency in a simulator but I seem to remember he found the actual emergency different to how the simulator behaved. He reached a 20 degree yaw when he reduced airspeed to 96kts and was concerned he might lose control if he reduced power further so he did a fast run on and the helicopter rolled over on the ground. If he had taken the speed back below 96kts, even though the yaw would have increased he could have reduced that once he applied collective at a lower speed. Easy for me to say in hindsight from my warm study!

Bell_222_G-METB_08-85-2.pdf

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[Boac]

FD2 - thanks for that comprehensive post - so Seen's 'many training hours' are in the simulator? As you say, I expect 'the real thing' is a bit different. I'll stick with kudos to that pilot, I think.

[Seenenough]

FD2 - thanks for that comprehensive post - so Seen's 'many training hours' are in the simulator? As you say, I expect 'the real thing' is a bit different. I'll stick with kudos to that pilot, I think.

You are absolutely correct,there is no way to simulate loss of tail rotor drive but I suspect that the situation would be similar to loosing control authority,but in reality,no situation is the same as the 'real thing'

I know of a South Arican pilot ,working for ESKOM, who managed to walk away from a situation where his own tail rotors chopped of his tail boom on a 407.Sadly he died in another incident(R.I.P Jimmy)

In the "real thing' situation , all you are trying to do is survive the landing-the resultant condition of the machine is not important.The pilot of this 139 managed to get it right.

My point is that many hours of emergency procedure traning makes such a situation survivable.

How was it that the pilot managed to save the lives of all aboard here-it is simple he likely trained for many hours to do it when the 'real situation"arose.

There is a youtube video of a pilot landing an Enstrom 280 landing without tail authority.

[FD2]

Total loss of tail rotor can, for obvious reasons, only be 'practised' in a simulator. Even then it's the best guess of the manufacturers as to how the machine will react for real when there is no tail rotor input. C16 has summed it up brilliantly. Aircraft with more fuselage behind the rotor centroid may be a little easier than something like the S61N with its large fuselage plug forward of the centroid.

At every 6 monthly VBC we practised landing with jammed pedals, but of course there was nothing we could practise about what we would do if we lost the tail rotor completely, except have the usual crewroom and classroom discussions . The Japanese pilot did brilliantly and common sense would make it very important that his handling technique and the aircraft's flight characteristics get passed back asap to Agusta/Leonardo or whoever makes the aircraft for incorporation in simulators, ERCs perhaps. Without being critical of his performance, it might be more interesting on instruments! Getting the gear down would help by reducing the spin at impact and maybe some vertical speed, but ultimately the slowest ground speed at impact will save lives of those properly strapped into their seats and surviving severe vertical impact and prevent the aircraft being torn apart if it hits the ground at speed.

[Seenenough]

Total loss of tail rotor can, for obvious reasons, only be 'practised' in a simulator. Even then it's the best guess of the manufacturers as to how the machine will react for real when there is no tail rotor input. C16 has summed it up brilliantly. Aircraft with more fuselage behind the rotor centroid may be a little easier than something like the S61N with its large fuselage plug forward of the centroid.

At every 6 monthly VBC we practised landing with jammed pedals, but of course there was nothing we could practise about what we would do if we lost the tail rotor completely, except have the usual crewroom and classroom discussions . The Japanese pilot did brilliantly and common sense would make it very important that his handling technique and the aircraft's flight characteristics get passed back asap to Agusta/Leonardo or whoever makes the aircraft for incorporation in simulators, ERCs perhaps. Without being critical of his performance, it might be more interesting on instruments! Getting the gear down would help by reducing the spin at impact and maybe some vertical speed, but ultimately the slowest ground speed at impact will save lives of those properly strapped into their seats and surviving severe vertical impact and prevent the aircraft being torn apart if it hits the ground at speed.

In the end it all comes down to training ,training and training as to how successful we we be in a 'real situation'-simple

Think of it-landing a 407 with no tail rotor left attached at all.Was it luck or was there some good training that took place before the incident?-Bell sent test peole out to interview Jimmy as to how he managed it.

[FD2]

seenenough - I would contend that the only training you can do to cope with this emergency is to handle the aircraft as proficiently as possible, because you will never know in advance how it will behave. You make control inputs to hopefully counteract the aircraft's behaviour, drop the lever, shut down the engine(s), get the gear down and hope to be able to cushion the impact at the bottom, enough to stay alive. There is no 'training' that can allow this except in a simulator.

How could any 'training' have helped the 407 down, apart from skilful handling, luck and following 'suggested' handling techniques?

[Seenenough]

seenenough - I would contend that the only training you can do to cope with this emergency is to handle the aircraft as proficiently as possible, because you will never know in advance how it will behave. You make control inputs to hopefully counteract the aircraft's behaviour, drop the lever, shut down the engine(s), get the gear down and hope to be able to cushion the impact at the bottom, enough to stay alive. There is no 'training' that can allow this except in a simulator.

How could any 'training' have helped the 407 down, apart from skilful handling, luck and following 'suggested' handling techniques?

it all comes down to good training ,in the end ,as to how successful the outcome will be in the event of a real failure.The more you practice the luckier you will be.

In the 139 case the impact with the ground was not fatal and unti lthe pilot speaks we can only wonder how he got it right.

As to Dennis Kenyon-these is also a video of him getting it totally wrong and making solid contact with the ground.

[CharlieOneSix]

FD2 - I think we shall have to accept that with our combined 70 odd years flying helicopters we have been complicating things. Tail rotor failures are obviously 'simple'.

We have missed out on not being able to practice similar emergencies to that experienced by the guy with the 407 loss of tail rotor - obviously his success was down to his good training after he chopped off his own tail boom and therefore his tail rotor but I'm in the dark as to how he practiced that. Surely he was trained in the first place on how to avoid chopping off his own tail boom?

You and I were discussing our friend Colin B recently. One of the best pilots I had ever flown with and a superb ex-military and civilian instructor and CAA examiner. Obviously he didn't practice tail rotor failure enough or he wouldn't have been killed when he lost his tail rotor.

I think I've exhausted my opinions on tail rotor failures in this thread.

[FD2]

+1 - I agree.

[Seenenough]

FD2 - I think we shall have to accept that with our combined 70 odd years flying helicopters we have been complicating things. Tail rotor failures are obviously 'simple'.

We have missed out on not being able to practice similar emergencies to that experienced by the guy with the 407 loss of tail rotor - obviously his success was down to his good training after he chopped off his own tail boom and therefore his tail rotor but I'm in the dark as to how he practiced that. Surely he was trained in the first place on how to avoid chopping off his own tail boom?

You and I were discussing our friend Colin B recently. One of the best pilots I had ever flown with and a superb ex-military and civilian instructor and CAA examiner. Obviously he didn't practice tail rotor failure enough or he wouldn't have been killed when he lost his tail rotor.

I think I've exhausted my opinions on tail rotor failures in this thread.

Training buy your position seems to serve no purpose.

[Seenenough]

FD2 - I think we shall have to accept that with our combined 70 odd years flying helicopters we have been complicating things. Tail rotor failures are obviously 'simple'.

We have missed out on not being able to practice similar emergencies to that experienced by the guy with the 407 loss of tail rotor - obviously his success was down to his good training after he chopped off his own tail boom and therefore his tail rotor but I'm in the dark as to how he practiced that. Surely he was trained in the first place on how to avoid chopping off his own tail boom?

You and I were discussing our friend Colin B recently. One of the best pilots I had ever flown with and a superb ex-military and civilian instructor and CAA examiner. Obviously he didn't practice tail rotor failure enough or he wouldn't have been killed when he lost his tail rotor.

I think I've exhausted my opinions on tail rotor failures in this thread

Emergenct Training by your position serves no purpose-Why do we even bother to practice emergencies?