Hong Kong GFS Superpuma ditches in Reservoir after engine failure

[Runway101]

News at 7:30 TVB Pearl:

mDtTwlIk8yI

From RTHK (http://www.rthk.org.hk/rthk/news/englishnews/20101227/news_20101227_56_722588.htm):

A Government Flying Services helicopter has come down in the Shing Mun Reservoir after one of its engines failed.

All three crew members managed to swim ashore. They are reportedly in good condition and have been taken to Yan Chai hospital for a check-up.

The helicopter was participating in the aftermath of a wildfire when police say one of its engines failed and the machine went down.

An R-T-H-K reporter at the scene says an inflatable device kept the chopper afloat while the crew clambered out and swam to safety.

[skadi]

Not the worst place for a controlled dichting...

skadi

[ShyTorque]

Well done to the crew!

...but now how will they get the aircraft out? A possibility of water pollution issues here!

[ReverseFlight]

Well done for breaking the news, R101 : the local media has been very hush-hush about this one. Any landing from which you can swim away from must be a good landing. :ugh:

To our friends at GFS : Get off your high horse and admit your crew and aircraft are not infallible. Isn’t the stringent cadet recruitment and training supposed to eliminate this sort of thing ? And did it surprise you that twin engines did not provide you with the redundancy when most needed ? Go back to flight school and start all over again. Or just stick to what you do best – VIP harbour scenic flights – in fact it’s the only thing you can manage with any degree of success.

To our friends at HKCAD : Remind yourselves that GFS is not above the law (i.e. you). Don’t sweep it under the carpet and run for cover to avoid personal early retirement. You as regulator should review their HOGE procedures or, better still, direct them to subcontract what they are incapable of doing to those who know how to do it properly. Jack of all trades, master of none.

To our friends at SkyShuttle : You will be too aware of what happens during OEI, despite official statements about twin engines to put the public at ease. Don’t try and make a run for it because you know you will end up in the drink whatever the manufacturers say. Keep your wits, and keep your job.

To our friends at HKAC : Stop playing expert at this game. What you know is less than one-tenth of the knowledge required to fly a single-engined helicopter (never mind twins). Don’t criticize or belittle others’ flying techniques, as yours is totally inept and it will bite you hard one day. Stay humble and learn elsewhere, as your local instructor knows even less than you do.

Enough rant from my soapbox.

[ShyTorque]

Isn’t the stringent cadet recruitment and training supposed to eliminate this sort of thing ?

Eliminate what?

[Epiphany]

Sounds to me as if Miss Reverse Flight's job application was rejected by GFS but the hefty chip is still in place. Get over it.

Sky Shuttle operate AW139's as far as I am aware and fly CAT A procedures - which if flown correctly will eliminate ditching. GFS do not operate CAT A because of the nature of the job and the aircraft that they use.

GFS are one of the most capable and professional helicopter operators around. Seems to me that the training the crews receive paid off in this incident.

Well done to the crew.

[Runway101]

According to the PR (http://www.info.gov.hk/gia/general/201012/27/P201012270132.htm) it happened during firefighting op while picking up water. This would put them not very high over the reservoir...

[Non-PC Plod]

Looks like Santa didnt get to the Reverseflight household this year!

[leopold bloom]

Eliminated Reverse Flight for a start!
Engine wound down in the hover according to my sources.Well done boys, on the positive side you can tick off a ditching drill and a swim test!:D

[ShyTorque]

Eliminated Reverse Flight for a start!

Nice one! :D

GFS definitely operate well outside Cat A, especially when fire bucketing.

[R.OCKAPE]

GFS are one of the most capable and professional helicopter operators around. Seems to me that the training the crews receive paid off in this incident I had a few close calls with their capable and professional procedures

one in particular was in a Lama at the end of a 200' line about to lift a load off a barge while they circled around 200' above in a Super Puma ,

... another occasion reporting us for our rotor disk being over CLK south road when picking up from our CAD appoved pick up location adjacent the waterfront in the hover again at the end of a 200' line , which was dismissed I might add

numerous times broadcasting intentions or positions which were totally wrong

, busting controlled airspace without clearances , or not complying with ATC directions....

...ignoring radio calls from other helicopters directed at them to advise of a potential conflict in flight....

they have the attitude they are a law unto themselves and had complete rights to HK airspace above anyone else.

...and ask the ATC controllers at CLK what they think of the GFS if you want a second opinion

their fire fighting capability's are limited to nothing more than psychological reassurance for HK residents

(I'm not saying I'm without fault , I've made some poor operational decisions in my time, got caught and paid my dues)

[Runway101]

I just added this youtube video (http://www.youtube.com/watch?v=mDtTwlIk8yI) to the first post. Seems a photographer was actually taking pictures when they popped the floats...

[AGNES]

R. OCKAPE,

I totally agreed with you. The GFS crew should learn from the crew of Skyshuttle and Heliservices of how to fly in a controlled airspace. Very poor airmanship indeed!

The accident over Tung Chung Pass was forgotten.

I really missed the crew of the RAF before 1997. They were real professionals.

[Runway101]

Since we seem to have the local helicopter community here, is it true that the current president of the HKAC is a former GFS pilot?

(In case this is too off topic, feel free to use the PM function)

[ReverseFlight]

King Air, RHS.

[DECU MAJOR]

GFS are one of the most capable and professional helicopter operators around. Seems to me that the training the crews receive paid off in this incident.

???:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:

[Epiphany]

Get turned down as well eh?

Perhaps they could learn a thing or two from you '20 minuters'. Must be a difficult job flying between HK and Macau.

[sox6]

So much negativity here.

[ShyTorque]

I totally agreed with you. The GFS crew should learn from the crew of Skyshuttle and Heliservices of how to fly in a controlled airspace. Very poor airmanship indeed!

What on earth have comments like that have to do with this incident? :ugh:

Looks like a text book ditching to me. Thankfully the crew safely jettisoned the firebucket and minimised further loss or damage.

Is this the second time that same bucket has gone to the bottom of that reservoir I wonder? :E

btw, for the less informed; GFS has its foundations in the British Military crewfolk who were there at its inception.

Get turned down as well eh?

Perhaps they could learn a thing or two from you '20 minuters'. Must be a difficult job flying between HK and Macau.

So does the organisation here disrespectfully know here as "20 minuters". Perhaps those affected by the green eyed monster have forgotten the airmanship and skill shown by the crew of the A139 that lost its tail rotor and also successfully ditched not too long back.

[trex450]

OK I am not a helicopter pilot but is it possible that having filled the water bucket they had the engine failure at close to max weight (assumption) which I guess means that they cannot hold the hover on one engine. The release handle is pulled and nothing happens. Now they settle into a low hover above the bucket which is visible on the surface and no longer affecting the weight of the aircraft. They can hold the hover but not go anywhere so surely the least risky option is to pop the floats out and land on, swim to shore and recover the un broken helicopter later.

Pure speculation of course, unacceptable to many I know and I shall now duck under the keyboard

[Cabe LeCutter]

Well Reverse and Rockape,

What a bitter and warped load of drivel that you spout on this forum. I grant you that GFS is not perfect, occasionally guys do make mistakes but then so do we all. The advantage that GFS has is that they never claim to be perfect; I have not heard any of them slagging off Heliservices for wrapping a load and sling around a pylon and power cables a few weeks ago, Skyshuttle cannot claim to be perfect either.
It is about time that people realise that GFS do not fly from A to B, they do the full gambit of task including SF, but all within the rules albeit with exemptions for some tasks; sometimes things go wrong and as they are flying close to the limit, the outcome can be bad, they learn from their mistakes, do you?

I suggest that you wait for the outcome of the Investigation before you vent your bitterness against GFS. With comments such as you have both made, I can understand why you failed the selection.

Head down, look out for the flack

[Jimmy does SAR]

As one of the ex-military SAR personnel who was responsible on occasion for conducting independent audits of GFS I always found them to be totally professional. Some of the previous comments about GFS seem to be completely misinformed, even libelous (if the individuals repeated them without the protection of anonymity). Can't comment on this incident as who would believe anything that's been reported to date?

[Runway101]

HK probes helicopter mishap (from RTHK (http://www.rthk.org.hk/rthk/news/englishnews/20101228/news_20101228_56_722690.htm))

A GFS helicopter comes down in the Shing Mun Reservoir. Photo: Simon Lee
The Hong Kong Government Flying Service has grounded all three of its Super Puma Mark Two helicopters after engine trouble forced one to make an emergency landing in the Shing Mun reservoir.

The three crew members escaped unharmed. An investigation is underway into the incident.

The helicopter involved in Monday's incident was taking part in a hill-fire operation and flying low, lifting buckets of water from the Shing Mun Reservoir, when an engine problem prevented it from climbing. The pilot then made an emergency landing into the reservoir, several hundred metres from the shore.

An inflatable device kept the helicopter afloat while the three crew members climbed into the water and swam to safety. They were taken to Yan Chai hospital for examination and released.

Director-General of Civil Aviation Norman Lo said an investigation will look at all factors, including any mechanical problems affecting the Super Puma Mark 2 helicopter. Mr Lo said the craft had gone through regular maintenance and was up to service standards.

Engineers from the French maker of the Supa Puma helicopter will carry out checks on the government's three aircraft. The helicopter involved in Monday's incident has been in service since 2001 and has accumulated more than 5,000 flying hours.

Michael Chan, Controller of the Government Flying Service, said the chopper's age was not thought to be a factor in the accident. He praised the pilot for making the right call by performing an emergency landing. He said the move ensured the crew's safety.

The helicopter will be partially disassembled, then airlifted from the site. The recovery operation is expected to take days.

Engineers from the Water Services Department took samples of the reservoir water for tests, but there was no immediate sign of contamination to the supply.

Floats were used to cordon off the chopper to guard against any oil spill.

[jackx123]

GFS has its foundations in the British Military crewfolk who were there at its inceptionI love the underdog but thought the british military got their a## whipped ever since the vikings ravaged them for 300 years, not to mention afghanistan.





What does listing 300 year old battles have to do with this thread, or with the beginnings of the GFS with help from the RAF?

:=

Senior Pilot

[jackx123]

That's precisely my point inception is one thing and current is another.

And because the british military helps someone out doesn't necessarily mean it's a great advantage, hence pointing to history.

It seems I offended you Mr. Senior Pilot and apologize for it.

Long live the Queen

[oldbeefer]

As the CFS Helicopter Examiner, I made 5 visits to the HKAAF and to GFS when the name changed. I rarely found anything other than a well trained and well run outfit.

[R.OCKAPE]

you didn't see anything you didn't want to see

[tomotomp]

oldbeefer that must of been at least 15 years ago, things can change.

[SHortshaft]

I didn’t expect to read some of the comments made on this thread on this forum. I kind of hoped we were better than that...but then mankind never fails to disappoint me. I would like to think that they wouldn’t have been said if HKG was still a British Crown Colony (STIC!).

I thought TREX450 got close to asking an interesting question; with the external load bucket jettisoned surely the aircraft could have flown away on one engine. I am not inferring an error on the crew's part, perhaps there were additional problems that we are not aware of that made a ditching the best course of action.

A one-engine-inoperative recovery to the GFS base would have saved the GFS a massive recovery and repair expense and not necessarily have increased the risk, as a ditching and evacuation has its own set of risks.

[Ned-Air2Air]

Few questions for those in the know.

Q - Are the GFS Super Pumas fitted out with a lot of kit, hence making OEI a moot issue.

Q - Was it a really hot day when they were fighting the fire and was it up high.

Q - If they lost an engine wouldnt there have been enough power to at least get to the edge of the dam they were working out of.

Maybe someone with knowledge of the Super Puma MKII could answer some of these. And no they arent for any specific purpose, just curious whether there were other issues besides the engine failure.

Cheers.

Ned

[Epiphany]

If this was a GFS operational flight then I doubt that operating at OEI weights was much of a consideration. Training yes - operations no. Even with only 3 crew onboard if it was full of fuel and hot and high in a low hover picking up a heavy load of water then ditching would have been the only option for the Super Puma.

Same for SAR. This is not CAT A passenger carrying flying. You fill up to get the job done - not to plan for an OEI fly away.

The crew would have briefed the OEI scenario after observing the hover TQ at the start of the lift and would have ben expecting to ditch in the event of OEI. Which seems to be exactly what they did.

surely the aircraft could have flown away on one engine.

Short shaft - you would probably be asking why they didn't ditch if they had attempted to fly away on one engine and crashed.

[ShyTorque]

with the external load bucket jettisoned surely the aircraft could have flown away on one engine.

Are "pilots" posting stuff like this really being serious? There are very few twin engined helicopters that are capable of an OEI flyaway from a hover in a situation like this.

Shame the "old" (not very) S-70s had to go, though ....

[SHortshaft]

Oh dear ShyTorque, you have done it again...more disappointment!

Whilst I understand that there are very few twin engine helicopters that are capable of an OEI flyaway from the hover I was led to believe by my friendly Eurocopter Salesman that the Super Puma Mk II was perhaps one of them.

With only 3 crew and a ‘reasonable’ amount of fuel, an OAT of less than ISA+5, and only a few hundred feet altitude, I queried whether the aircraft could have flown away. Maybe a Super Puma expert who sleeps with a RFM under his pillow could advise on that point.

If I am supposed to think that I should ditch a multi-engine helicopter just because an engine has malfunctioned then we are using Royal Navy thinking and perhaps we should consider going back to single engine helicopters.

[ShyTorque]

Whilst I understand that there are very few twin engine helicopters that are capable of an OEI flyaway from the hover I was led to believe by my friendly Eurocopter Salesman that the Super Puma Mk II was perhaps one of them.

Really? So you perhaps bought one, right?
But then you would perhaps need a twin rating. Judging by your profile, you perhaps don't have one.

Perhaps best to wait for the results of the inquiry, eh? :hmm:

[Epiphany]

If I am supposed to think that I should ditch a multi-engine helicopter just because an engine has malfunctioned then we are using Royal Navy thinking and perhaps we should consider going back to single engine helicopters.

You are showing your ignorance of multi-engine helicopter operations Shortshaft. As Shy Torque says you should probably spend some time in a multi-engine helicopter. If you had then you would not be making such ridiculous comments.

If you believe everything that a helicopter salesman tell you then you are also demonstrating an extraordinary level of naivety.

[Fareastdriver]

Having carrid out an uncountable number of winching operations in the South China Sea can I put my oar in.
Some twin-engined helicopters will fly away from a OEI situation if it is cold and windy enough. Unfortunately for most twin engined helicopters those situations are too rare. The 332L1 to the best of my memory will hover OEI OGE at about 12,500 lbs with Zero wind in the Hong Kong area, which equates to just the crew and no fuel. Things get a lot better when there is some wind.

http://i229.photobucket.com/albums/ee224/fareastdriver/Winching010.jpg

That was me winching inside the OEI curve with 7 knots plus 5 knots from the tanker with 2,000 lbs of fuel on board at about 28.C. Add 800 lbs for mooring crew and it come to about 15,300 lbs. It could have been a lot more, the 2,000lbs just happened to be hanging about. Twenty knots or so and you were above Max weight.

THE OEI HOVER OGE IN MY CASE WAS A PUBLIC TRANSPORT REQUIREMENT.

These same wind conditions would give you flyaway whilst on SAR duties if the weights were the same. Normally when offshore there is a fair amount of wind which keeps the OEI curve well up the weight scale. When the wind drops the picture changes; judging by the weather history and the video in this case they had less than five knots.

There is a not a lot of differences in hover performance betweeen an L1 and an L2. With any sort of fuel load plus what an SAR helicopters carries they were not going to fly away. Pickling the water tank might have slowed the rate of descent but when the floats went off they will have been dragged into the water.

I would not have thought that the GFS would have worried too much about OEI flyaway. Their previous chariot, the Sikorsky S76C resembled a brick if an engine stopped in the hover so that was what they were used to.

Personally, all things being taken into consideration, they did as well as anybody could be expected to do in the circumstances.

[ShyTorque]

Personally, all things being taken into consideration, they did as well as anybody could be expected to do in the circumstances.

Well said!

I agree about the S-76C previously used by GFS (albeit not for the SAR role, they were the A++ version). Torque readings of 90/90 didn't do much for the confidence when hovering, especially over a ship.

[SHortshaft]

Thank you Fareastdriver, your informative posting is appreciated.

[Pilot DAR]

It's sad to see those rather negatives posted here by a few. I think there is an "axe grinding" thread elsewhere....

Though I have zero knowledge of the events of this accident, my time working with the people of GFS (two occasions, totalling three weeks) left me very impresed with the way things are done there.

My experience with GFS, included an afternoon of fixed wing flying, and another afternoon aboard a helicopter training flight. The crews were methodical, prepared, and relaxed. The flying in both cases demonstrated everything I would be looking to see in an operation, whose demands are so varied.

Similarly, the maintenance at GFS gets my highest regards.

No matter how well you maintain, and how well you fly, stuff occasionally happens. It sounds like they made the best of a not good situation, and damage was well mitigated. Let's extend to our aviation colleagues the benefit of our courtesy in respect of their operations. I doubt I could do better than they do, so I don't feel a need to criticise...

[handbag]

Are "pilots" posting stuff like this really being serious?

The height of arrogance there captain Shyte Talk. There are plenty of pro pilots reading and contributing to this forum that have not progressed/upgraded/transcended ( delete as appropriate ) to multi ships and still have much to offer. Maybe a new years resolution is order ? I doubt it though. :suspect:

[ShyTorque]

The height of arrogance there captain Shyte Talk. There are plenty of pro pilots reading and contributing to this forum that have not progressed/upgraded/transcended ( delete as appropriate ) to multi ships and still have much to offer. Maybe a new years resolution is order ? I doubt it though.

There is more than a little arrogance in your own post. I answered in the way I have only because more than one pilot waded straight into this crew; spouting off in a highly critical way about something of which they obviously have no relevant knowledge.

Of course other "pro pilots" have a lot to offer. However, back stabbing other crews after an flying accident isn't a professional way to go about it.

The crew in this incident did a very good job in saving the aircraft, thankfully without it resulting in loss of life or causing damage.

I do have some understanding of the often very difficult multi-role job the GFS crews have, quite a bit more than others here have demonstrated. I also know that GFS crews have been told in the past not to post on this forum and so are unable to stand up to the unfair criticism for themselves.

[Heliport]

handbag

Pleased to see you've withdrawn your unjustified personal attack. :ok:

Genuine questions are answered, usually patiently and politely. However, there's a big difference between asking genuine questions and making sweeping ill-informed assertions.
When people do the latter they are, not surprisingly, likely to be shot down by experienced pilots - whose understandable exasperation sometimes shows.

H.

[Nubian]

bigskyheli,

Not too nitpick too much, but I guess you're referring to a R-22 ending up in the frontseat of the bus, not a 44 (unless this is a regular occurance of course)
And not to de-rail the thread further, what does the Hong Kong flying Club have to do with a L2 Superpuma ditching while on fire-ops??
As for your consern of downwind approaches, it's up to you (captain) to decide what you want to do. (within your and a/c's capabilities, and feeling)

As for twins OEI capabilities, comment's like, surely the aircraft could have flown away on one engine most likely come from people that don't have experience with twin-ops.

Almost NO twins(few exceptions though) are able to fly away from that scenario with a reasonable workingload of fuel and OGE hover (not high enough!!) I guess the outcome would have been different if the bucket was at the end of a longline, but then again it wasn't....

[Nigel Osborn]

If only they had a Wessex Mk5!!!:ok:

[ShyTorque]

Yes, then they would have had to use the small bucket...... ;)

[Nigel Osborn]

4000 lbs or a long wheel base Landrover or a 105 howitzer!:ok:

[[email protected]]

But not enough fuel to take it anywhere useful:{

We did a lot of firebucketing in Cyprus on Mk5s converted to Mk 2 spec and fuel was always the big issue, especially if you were using a reservoir in the hills.

At least you never needed to worry about getting a good overhead when lifting the bucket, just pull 3200lbsft and wait - the load brought the aircraft to the overhead and you gradually staggered airborne:ok:

Even with the Wessex's enviable SE performance, an engine fail in the hover with a full bucket would have meant getting wet!

[ShyTorque]

I think the GFS firebucket bucket weighs more than 4000 lbs.

[R.OCKAPE]

what is the capacity in litres of the buckets they use?

[malabo]

So did the engine quit on its own, or was it pilot induced?

All face saving aside, isn't that the real question?

[griffothefog]

Of course there is always black and white in these situations, those that defend and those that attack for whatever reason....:{

Personally, I think it went beep beeep beeeep beeeeeep splosh :E

The crew probably did a good job in doing nothing, other than recognising the noise and hitting the release button..... :ok:

Happy new year and safe flying......

GTF.

[molen]

A link to some very clear images of the Super Puma involved:

JetPhotos.Net Aviation Photos-Registration Search: B-HRN (http://www.jetphotos.net/showphotos.php?regsearch=B-HRN)

http://images3.jetphotos.net/img/2/0/3/0/85574_1293629030.jpg

http://images3.jetphotos.net/img/1/3/0/1/40520_1293628103.jpg

[Runway101]

Thanks for the images. I was up at the reservoir for a hike on Friday but they were already gone (I watched a monkey steal a DSLR camera instead, sadly it went up on a tree with it and dropped it on a stone :ugh:).

It has been reported that the remaining two Superpumas at the GFS are now back in service.

Unfortunately in the case of the HKFC you were not allowed to fly there unless you followed the one and only landing procedure, regardless of the wind. This policy was guaranteed to result in an accident. The CAD report on that accident never mentioned the club's policy on the mandatory landing direction, surprise.

I am with you that this one and only approach procedure is BS and I am not here to defend the HKAC or the HKCAD and this is still off-topic, but you clearly need a new pair of glasses. In the report there is a whole paragraph about this limitation. What surprised me more is that there is no mention that downwind approaches are normally avoided like the plague.

I've actually seen your AS355N turning into the wind above Olympic Ave and coming in from the other direction, and that was prior the R22 accident. Clearly somebody at your company (or MFW) knows what they are doing :D

Anyways... back to topic.

[oldbeefer]

"that must have been 15 yrs ago"

Very true - how time does fly!:{

[Ikoyian]

Goodness, how much does a Mk2 weigh? They have it suspended from that rather thin branch on the tree:E

Now come on lads, get that tank flushed out and those floats re-packed, we need it flying first thing tomorrow:}

Just kidding of course:O

[Thud_and_Blunder]

Nige Osborn,

If only they had a Wessex Mk5!!!

We used the 1200lb firebucket on the Mk2 Wessie on 28; occasionally effective, but then again so is getting the crewman to p1ss into the chrome-plated receptacle. Was once tasked to assist in quelling a disturbance at Stanley prison by firebucketing the prisoners but I refused - half a ton of water delivered from the hover (as requested) would've been 'excessive force'.

[leopold bloom]

Rock Ape - From memory the bucket holds between 800 and 500 US gallons depending on how many bungs were inserted. That's roughly about 3,300 Kgs and 2000 kgs respectively. The bucket itself weighed in at about 275 Kgs, internally there were also a couple of tanks holding foaming fluid.

Oldbeefer - GFS still have regular visits from the RAF SAR Standards Unit and CoSARM, they have also had RN fixed wing standards in to look at the Jetstream operations. They are still a top class outfit.:ok:

[[email protected]]

Thud - I know someone who firebucketed a passing out parade at the HK police HQ!!!

[Ned-Air2Air]

I thought the GFS machines all had belly tanks. Shot this a while ago.

http://i54.photobucket.com/albums/g100/KiwiNed/a27.jpg

[ShyTorque]

The belly tank needs time to fit, especially if the aircraft is previously roled for SAR. A bucket can be picked up on the USL hook far more quickly.

[leopold bloom]

Only one tank between the three L2's.

[206Fan]

uboovnxksHk

[Chi Sin Gei Si]

Very cool video!

Welcome to Hong Kong...for all those who thought it was just high-rise!

[ShyTorque]

Wow! Fascinating! :)

(No, I mean the video; I know it's not all high-rise).

[leopold bloom]

Great video, don't they work quickly in HK? Blue skies and no monkeys too.:D

[Pilot DAR]

What a really great video, my compliments to the producer!

I'm now imagining the Puma sitting on a trailer, pointed down a rather narrow road, toward GFS. Perhaps they'll get it to a barge to make the transport easier. I wish them an easy go of it...

[Adam Nams]

Blue skies and no monkeys too.:D

Yes, it was their day off (FTL).

I saw on the news that the heli was on a low loader and back in the hangar that evening. Good job by all involved :ok:

[Runway101]

Preliminary report here:

http://www.cad.gov.hk/reports/B-HRN%20Preliminary%20Report%202-2011_eng.pdf

The combined voice and flight data recorder (CVFDR) was undamaged and removed from the helicopter safely. The data in the CVFDR was later retrieved with the assistance of Eurocopter and an initial analysis of the data was conducted. It revealed that the helicopter had experienced a power turbine overspeed on No. 2 engine, and the overspeed caused an automatic shutdown of the engine. The reason of the overspeed is under investigation.