Helicopter down outside Leicester City Football Club

[[email protected]]

Rattle - the AP(s) will be engaged, probably in ATT mode but not the flight director modes. The pilot is manually flying the aircraft but with AP stability assistance. He might engage a FD mode after the transition (ALTA for example).

[John Eacott]

Forget the false idea that the pilot suffered ‘night blindness’ climbing out of the soccer stadium: there is ample ambient light from the surrounding built up area to give situational awareness and a solid horizon. After years of similar operations with the AW169 and preceding that the A109 the fearmongering implication of your post is nonsensical.

Checking with AW169 Pilots the departure procedure is absolutely in accordance with the Flight Manual, and raising the gear after 200ft is bog standard checklist stuff.

[dingo9]

Forget the false idea that the pilot suffered ‘night blindness’ climbing out of the soccer stadium: there is ample ambient light from the surrounding built up area to give situational awareness and a solid horizon. After years of similar operations with the AW169 and preceding that the A109 the fearmongering implication of your post is nonsensical.

Checking with AW169 Pilots the departure procedure is absolutely in accordance with the Flight Manual, and raising the gear after 200ft is bog standard checklist stuff.
similar types is 200’ AND Vtoss to raise gear. You want them down for the reject. Red herring anyway as the would’ve made c&@ck all difference here.

[Hovering-is-devine]

gear up is obviously not always 200 Ft but in case of extended TDP gear up happens after TDP … logical since you must go back to the ground in case of engine failure before

[rattle]

Rattle - the AP(s) will be engaged, probably in ATT mode but not the flight director modes. The pilot is manually flying the aircraft but with AP stability assistance. He might engage a FD mode after the transition (ALTA for example).

Thank you.

[anchorhold]

John Eacott states....'Forget the false idea that the pilot suffered ‘night blindness.

It is not a case of complete blindness, however we are all taught through HP& L training that the eye takes some time to accommodate from daylight conditions to night conditions. I would be very surprised if this is not mentioned under human factors in the final report.

[JerryG]

During rehearsals for the Melbourne Commonwealth Games in 2006 we had to ditch the idea of using the Bolte Bridge during the opening ceremony because the upward facing lights attracted large numbers of moths, which in turn attracted large numbers of circling birds; mainly seagulls. It happened every night during summer and autumn. Just a thought.

[EESDL]

Thank heavens someone pointed out that 'gear up' varies according to what sort of departure you are doing.
So, if I have to climb to a 400' TDP, someone whom should know better suggested raising gear at 200'
Is this symptomatic of something else in the industry or can we simply assume NO ONE WOULD EVER RAISE THE GEAR BEFORE TDP?

[FlyHiGuy]

Yes and were seen still facing into wind before lifting. Why on earth do a 180 turn to depart downwind?
I'm not sure if this would explain it but in VIP ops, often the crew would position the direction of the nose to ensure that the VIP pax gets out and can directly walk to or enter from his destination (in this case it seems that from the other video footage that he was coming out from a stadium gate to the heli). This way, the VIP does not need to walk around the nose (or tail!) to go to his walking destination. The 180 turn could have been to reposition the nose into the winds when they reached above the stadium structure. Just a thought...

[WHBM]

I'm not sure if this would explain it but in VIP ops, often the crew would position the direction of the nose to ensure that the VIP pax gets out and can directly walk to or enter from his destination .
No different to an airliner at the gate then ...

Regarding crew qualification, I suspect the pointed expression "Passenger" used in news reports to describe the left seat occupant, but not the remainder of those on board comes from the AAIB on site. Having peripherally observed a not dissimilar GA situation with qualified pilot and another without the right qualifications (actually the airframe owner), the AAIB report said "Passenger" almost every paragraph, to make their point.

[industry insider]

I hear what you are saying but surely the two pilots must at least have a licence for the vehicle that they are flying ie Helicopter or Aeroplane?

If the aircraft is certified for single pilot ops, there is no requirement other than a customer / owner one.

[nigelh]

My God have we not got it yet ???? V often a pax may feel safer having someone with some knowledge up front with the pilot . This is often due to fear of possible pilot incapacitation. I have done this over the years in many aircraft . This operation was single pilot but having someone capable with you to look outside , remember frequencies etc can only be a help . It looks like you are all willing there to be a legal problem .....

[silverelise]

Do we anticipate an incoming temporary flight suspension or emergency AD?

[Cabby]

Do we anticipate an incoming temporary flight suspension or emergency AD?

Have wondered the same thing about AD's? Any news from other AW169 owners, OR whoever provided the maintenance on the 169 involved in the crash?
The only AD's that I can see for the AW169 are enclosed in the PDF below..

https://www.caa.govt.nz/assets/legacy/Airworthiness_Directives/AW169.pdf

[Gulfstreamaviator]

Whilst I agree that 'any old pilot' in the other seat of a single crew operation could quite likely be a liability, the two Pilots in this case were both highly experienced Corporate Crew who had flow together professionally for a long time, understood CRM and had a wealth of knowledge between them, even if one was fixed not rotary.

Having flown single pilot ops in complex types many years ago I did appreciate a competent pilots assistant as they used to be termed. As long as they are briefed/trained in the scope of their input I have only seen it as a good thing.

[Cabby]

Have wondered the same thing about AD's? Any news from other AW169 owners, OR whoever provided the maintenance on the 169 involved in the crash?
The only AD's that I can see for the AW169 are enclosed in the PDF below..

https://www.caa.govt.nz/assets/legacy/Airworthiness_Directives/AW169.pdf

Some images of G-VSKP at a the Specialist Aviation Service maintenance company.
I believe they are the importer of the AW169 type into the UK.

When was the a/c last checked for the latest AD about the emergency windows being difficult to push out? 5th Sept AD posted earlier.
https://commons.wikimedia.org/wiki/File:G-VSKP_Agusta_AW169_Helicopter_Foxborough_Ltd_(28313983994).jp g

This photo taken in 2016 at same place.
https://commons.wikimedia.org/wiki/File:G-KSST_Specialist_Aviation_Services_Ltd_With_G-VSKP_Foxborough_Ltd_Two_Agusta_AW169_Helicopters_(2940133550 2).jpg

[anchorhold]

As we reach the end of day three of the AAIB investigation, the fact their are no ADs and the aircraft type has not been grounded suggests the following.

(a) There is no reason to suspect that the aircraft was in anyway defective.
(b) The primary causal factor is a result of the aircraft sustaining damage during flight as a result with contact with a structure or other object.
(c) If not (b) then due to the handling of the aircraft by the pilot in command, pax or both, either in error or intentionally.

[chopper2004]

https://cimg4.ibsrv.net/gimg/pprune.org-vbulletin/804x582/glcfc_bdf3449afc964e75719db41f616a16cdf1f35a97.jpg
Yep - very puzzling accident.
Clearly a highly experienced pilot apparently operating to SOPs - LTRE wouldn't seem to be a factor.
An almost brand new and very sophisticated machine - that one would assume was impeccably maintained.
Could there have been some sort of one off assembly or manufacturing fault that caused a catastrophic drive shaft or gearbox failure?
But then you'd think there'd be multiple independent checks of components at time of assembly?
Very strange...

Leonardo is assisting the AAIB according to their press release. Also mate of mine in Leics was quoting a local rumor of drone impact, which I believe was mentioned somewhere earlier in this thread. Has the stadium CCTV showed anything out of place on immediate lift off? Without digressing , sadly its two 'firsts' crashes this week.

Accident at Leicester City Football Club's stadium - DETAIL - Leonardo - Aerospace, Defence and Security (http://www.leonardocompany.com/en/-/incidente-accident-leicester-city-fc-stadium)

I do like a certain tabloid this morning that showed photo of G-LCFC when criticising the Beeb sports editor for his assumptions on the relationship between two members of the deceased

ATB
cheers

[ShyTorque]

As we reach the end of day three of the AAIB investigation, the fact their are no ADs and the aircraft type has not been grounded suggests the following.

(a) There is no reason to suspect that the aircraft was in anyway defective.
(b) The primary causal factor is a result of the aircraft sustaining damage during flight as a result with contact with a structure or other object.
(c) If not (b) then due to the handling of the aircraft by the pilot in command, pax or both, either in error or intentionally.

(d) The cause has not yet been positively determined by AAIB.

[Daifly]

As we reach the end of day three of the AAIB investigation, the fact their are no ADs and the aircraft type has not been grounded suggests the following.

(a) There is no reason to suspect that the aircraft was in anyway defective.
(b) The primary causal factor is a result of the aircraft sustaining damage during flight as a result with contact with a structure or other object.
(c) If not (b) then due to the handling of the aircraft by the pilot in command, pax or both, either in error or intentionally.

AAIB might as well go home then. When are you releasing your report? :D

[Dawdler]

(d) The cause has not yet been positively determined by AAIB.

Bravo Sir! At least someone has recognised that the investigations are still ongoing.

[runway30]

(Reuters) - The helicopter crash that killed Leicester City soccer club owner Vichai Srivaddhanaprabha was not caused by a police drone, Leicestershire Police said on Monday, as investigations continue into how the accident happened.

[exmanman]

https://www.thesun.co.uk/news/7620935/leicester-helicopter-crash-footage-stadium-fatal-spin/

[AnFI]

SASless: "The usual suspects are making statements of certainty already.....as is their habit...despite knowing nothing of what caused the accident."

I haven't

but this quote from JimL (a prime architect of the PC1 'upwards and backwards' take off that delivers 'engine accountability') might be pertinent:
"The arguement that simplicity is safer than complexity is a given, only the consequence of failure is in question"

Lets wait for the report, whatever it was, many here lost a great friend and a "top banana".
Always v sad for many people.

[Pittsextra]

(d) The cause has not yet been positively determined by AAIB.

Of course but actually you will struggle to find an example where the early rumour differs significantly in terms of the headline to the multi year final report...

Glasgow ran out of fuel...Shoreham pilot...North Sea EC225 let those down wearing big boy pants...etc

[Gustosomerset]

At frame 00.54 something appears to fly from above and to the right of the aircraft and then, at a different angle, move very fast off to the lower left of frame, around 5 second before it transitions into forward flight and immediately begins to rotate.

[Nige321]

At frame 00.54 something appears to fly from above and to the right of the aircraft and then, at a different angle, move very fast off to the lower left of frame, around 5 second before it transitions into forward flight and immediately begins to rotate.

It's an insect lit by the stadium lights, I get them on my CCTV daily...

[runway30]

https://www.thesun.co.uk/news/7620935/leicester-helicopter-crash-footage-stadium-fatal-spin/

Well that answers the could it have struck the stadium question.

[Nige321]

https://www.thesun.co.uk/news/7620935/leicester-helicopter-crash-footage-stadium-fatal-spin/

It's worth reading the article, even if it is the Sun...
One shaken witnesses told The Sun: “I’ve seen that helicopter take off lots of times, but I’ve never noticed it take so long to get up and stay up there in the same position in the sky for that length of time."Normally it goes straight up, and it’s gone.
“But this time, it seemed to take a long time to get up, and it stayed in the same place which seemed very unusual. Then, obviously, you know the rest.

[Barcli]

It's an insect lit by the stadium lights, I get them on my CCTV daily...

I am not convinced - given the direction of the downwash..... delamination of TR ?

[rlsbutler]

My flying career included virtually no experience of helicopters. I have followed this thread from the beginning. I cannot remember in the various lists of possible causes any suggestion of deliberate criminal action. Presumably, while the thought may not occur to Ppruners, there is an automatic forensic angle to the AAIB investigations.

[gulliBell]

From what appears to be original cctv footage released today..

The video of the departure taken from inside the stadium is pretty clear it didn't hit the structure of the building...
Anyway, what strikes me unusual is the puff of smoke from the engine as the rotor starts to turn....and vertical climb performance seems to deteriorate just before directional control is lost. Uncontained engine failure that severs the TR drive shaft?

[Nige321]

I am not convinced - given the direction of the downwash..... delamination of TR ?

Watch it again carefully, there’s loads of them...
Look at 1:02

[ShyTorque]

Of course but actually you will struggle to find an example where the early rumour differs significantly in terms of the headline to the multi year final report...

Glasgow ran out of fuel...Shoreham pilot...North Sea EC225 let those down wearing big boy pants...etc

The point is, any formal investigation of a tragic and high profile accident like this is going to take more than a couple of days. Some here seem to want an instant answer.

[EESDL]

There were remarks from a Bt Sport technician whom mentions he heard a definite ‘grinding’ noise - the sort you hear when accidentally selecting reverse......

[tomahawk98]

I've just watched the video - it seems that something clearly wasn't right with that tail rotor.

Anyway, scary that I was dealing with Eric professionally by e-mail not too many months ago. RIP to all. :(

[nevillestyke]

There were remarks from a Bt Sport technician whom mentions he heard a definite ‘grinding’ noise - the sort you hear when accidentally selecting reverse......
Could it have been a nearby car accidentally selecting reverse?

[Gustosomerset]

It's an insect lit by the stadium lights, I get them on my CCTV daily...
Yes, I'm sure you're right looking at it again. But this new clip does seem to go against the reports of odd noises or that the engine 'went quiet' before impact. The engine/rotor noise seems pretty constant....

[tomahawk98]

Just had a quick scan on YouTube to find some previous AW109/AW169s departures from the stadium:

I found this one: https://youtu.be/d7aQerzD65k?t=77

Although we shouldn't be making comparisons based on one video (especially as optical illusions could have their part too), the accident video shows the helicopter hovering for considerabably longer than the video above and it looks higher too.

Purely a very, very, very brief observation.

[GrayHorizonsHeli]

Some here seem to want an instant answer.

in the interest of further safety, thats not a bad thing is it?

[Lonewolf_50]

As we reach the end of day three of the AAIB investigation, the fact their are no ADs and the aircraft type has not been grounded suggests the following.

(a) There is no reason to suspect that the aircraft was in anyway defective.
(b) The primary causal factor is a result of the aircraft sustaining damage during flight as a result with contact with a structure or other object.
(c) If not (b) then due to the handling of the aircraft by the pilot in command, pax or both, either in error or intentionally. That is an irresponsible thing to post.
We for sure do not know a, but one can guess at anything. For b, primary causal factor is TBD. C. Maybe, and maybe not, but Where Are You Getting Intentionally From? That, sir (or madam) is utterly Irresponsible.

Dear members of the media who may wander by here, none of that which anchor posted is supported by information, given the lack of same.

Anchor: you are jumping the gun a bit there. I'd recommend dropping the short attention span act and waiting for the first (of many) reports. They'll be arriving in due course. Whether or not your guesses are close, or far, from the actuality will in time be shown. in the interest of further safety, thats not a bad thing is it? It is a bad thing if misinformation is spread by an instant, and wrong, answer. That's why fast isn't a good metric unless an early indication prompts the AIIB to issue an alert. Not jumping the gun is the AIIB being responsible, and doing their duty.

Regarding your idea of hitting something on the way in: what evidence are you pointing to that prompted that speculation?

[aox]

That is an irresponsible thing to post.
We for sure do not know a, but one can guess at anything. For b, primary causal factor is TBD. C. Maybe, but Where Are You Getting Intentionally From?
Irresponsible.
Dear members of the media who may wander by here, none of that which anchor posted is supported by information, given the lack of same.

Anchor: you are jumping the gun a bit there. I'd recommend dropping the short attention span act and waiting for the first (of many) reports. They'll be arriving in due course.

Fortunately the reports will be based on professional examination of evidence, not a need to react to poorly motivated baseless trolling.

[Lonewolf_50]

Fortunately the reports will be based on professional examination of evidence, not a need to react to poorly motivated baseless trolling. What got me to respond was the insinuation of intentionality. I do not feel that such ought to be left unchallenged. That, and me being aware of who may scan this site for tidbits to throw into a news story.

[GrayHorizonsHeli]

Regarding your idea of hitting something on the way in: what evidence are you pointing to that prompted that speculation?

hmmm i dunno...a spiralling out of control helicopter that appears to not hit a thing on its departure??? something somewhere had to have happened. But again, I digress, could have just as easily been a sleepy mechanic not torquing the bolts correctly. I see lots of things on the pictures and videos that pique my interest. the could haves that may turn into the cause.
If you're so upset about musings by others, leave the thread and don't come back. clearly you're drawn here for a reason though....is it to try and start fights?

The accident investigators aren't special by any means either. they cast a wide net, rule out things as they go along in a structured way. Nothing different going on here at all except it's not so structured. They just put it onto a nice dossier in the end and publish it.

[vaibronco]

Question from a PPL(H). Would autopilot ever be engaged on this sort of departure? At the top of the reverse climb? If there's a malfunction, does the computer compensate? How quickly can you disengage? Would it be used to allow the night blindness to settle having climbed out of a bowl lit for TV cameras into a night sky? It doesn't look sadly as there was ANY time to do anything but still interested to know the procedure for such eventualities.

About your question regarding blindness (and/or disorientation ?)

As crab said, the pilot manages manually in attitude mode the Cat A take-off till the limits (height and IAS) to engage the modes are reached.

Anyway if you find yourself very early in deep disorientation troubles, WLVL is an attitude function that will level your wings and bring your pitch 6 degrees up.

[aox]

What got me to respond was the insinuation of intentionality. I do not feel that such ought to be left unchallenged. That, and me being aware of who may scan this site for tidbits to throw into a news story.
​​​​​​To clarify, in case my post can be seen by anyone as any way ambiguous, I entirely agree with you.

Despite a couple of videos showing some aspects of the event pretty clearly, we still have people floating conjectures at odds with observable fact, such as fictitious collision with the stadium structure. If they haven't looked at the video themselves, they could at least believe those who have.

[malabo]

Possible pilot disorientation (nose up, black sky), then over-pitching?
I saw a careful professional departure, with very good handling skills and no evidence of over pitching or disorientation. What did pique my interest on that last video was the moment of rotation after the vertical climb. A the moment the nose is pitched downward (and again, it was not overpitched or overcontrolled, but rather the transition initiated by someone with experience), there appeared the beginning of a right yaw that was briefly stopped after which the aircraft again accelerated the yaw to the right. Rate of descent afterward seemed high as well, higher than you'd expect from bottoming the collective to reduce the uncontrolled yaw. Definitely looking forward to the AAIB preliminary. Anybody know if the AW169 has real-time HUMS or how ofter it is downloaded?

[KNIEVEL77]

It's worth reading the article, even if it is the Sun...

I have to agree with a quote from the Sun article.
I have a sequence of photos taken by me of a recent departure of this helicopter flown by the same crew.
The photos show the helicopter on the ground in the centre circle. Once the passengers have boarded the aircraft enters a low hover and turns 180 degrees, it then moves forward to the 18 yard line in a forward hover then moves backwards and upwards until it clears the stadium roof then transitions forward while climbing and off it goes.
However the departure shown in the Sun video is totally different to this, it seems to climb to a much greater height way above the stadium roof before making a turn.
This is purely my observation and the different departure technique may be for various operational reasons not to mention the wind direction but having seen this helicopter take off from the pitch on many occasions, I have never seen this departure technique used before from this location.

[jeepys]

As Malabo said this was a well flown departure all the way and one which I would expect from a professional pilot with experience. On this type of departure profile (confined area) flown from the RH seat you would yaw the a/c left to keep visual with the departure and possibly reject point in your chin bubble window. At TDP you would then yaw back to the right (30°) or so to straighten up. That's the procedure and that's what it looked like to me.

[Cabby]

While reading the various press details about business opponents in Thailand, it reminded me of a crash in 2004 where a wealthy buisnessman with Russian connections died after the A109 he was in burst into flames and crashed while approaching Bournemouth Airport in 2004. Even the local MP was sceptical about the crash findings at the time.

The coroner confirmed that he was aware of the death threats against the businessman Mr Curtis who was the CEO of Menatep which was owned by the Russian oil company Yukos. Mr Curtis died along with his pilot.
The coroner stated at the time - "that it had all the ingredients of an espionage thriller!” There was a mention of a Russian connection at the time of the crash.
https://www.bournemouthecho.co.uk/news/16080797.__39_It_was_no_accident__39___Doubts_over_official_ verdict_into_2004_fatal_helicopter_crash/

Re the press reports about the Thai businessman having opponents in Thailand. I noted in the article shown below, it reveals that last month a Thai court threw out a $430 million claim by the Airports of Thailand (AOT) regarding unpaid revenues by the Thai company King Power.
With the large amounts of involved, and the further mentions of opponents in Thailand, I wondered if anyone had a grudge against the chairman or his family?
https://www.today.ng/news/world/thai-court-rejects-lawsuit-company-leicester-city-owner-154035

More on the recent Thai court case.
https://www.yahoo.com/news/thailands-king-power-duty-free-empire-faces-unknown-094311688--spt.html?guccounter=1
Quote: "The license was secured from the state-owned Airports of Thailand (AOT) in 2006, after years of lobbying.
It gifts King Power the captive market of the near 40 million people expected to visit the country this year, many of whom trawl through its duty-free stores at Thailand's international airports or downtown mega-malls in Bangkok and Pattaya. Last month a court rejected an attempt to sue King Power for hundreds of millions of dollars in unpaid revenue to AoT.
That case was a rare pot shot by King Power's enemies. But without the shield provided by Vichai, the family could be vulnerable to avaricious rivals and moves to break up their monopoly.
"King Power's most important business is based on a monopolistic concessionary right granted by the government," explained Pavida Pananond, an academic at Thammasat Business School told AFP.
"That suggests the political nature of the business and Khun (honorific) Vichai's political and business clout.”
Whether his successors "move away from the 'know-who' to the 'know-how'" of the business will define how they parry potential competition, she said."

Other commentators have also discussed the Thai opponents, and the vast amounts of money involved.
https://thaipoliticalprisoners.wordpress.com/tag/king-power/

Maybe one for the intelligence services, as the pilot was very experienced, and the aircraft was only two years old.. :suspect:

[rotorrookie]

This all makes you think why bother these landings and take-off inside stadiums in general against having a helipad either on the roof or outside the bowl. Your are not in a good spot if something goes south, even if you are using a new high performance state of the art twin.

[John Eacott]

A YouTube of the crash footage, to avoid having to go to the tabloids:


https://www.youtube.com/watch?v=sS--OX-LPNU

[gulliBell]

As Malabo said this was a well flown departure all the way and one which I would expect from a professional pilot with experience...

Yep, I agree. But they seemed awfully high on the way up when things suddenly went pear shaped, given what I can make out of the height of the obstacles in the take-off path.

[jdwky]

This all makes you think why bother these landings and take-off inside stadiums in general against having a helipad either on the roof or outside the bowl. Your are not in a good spot if something goes south, even if you are using a new high performance state of the art twin.

Tell us a good helipad that could have survived this accident at the rate of descent they experienced?

[tartare]

Turned the volume right up and couldn't hear any bang or grinding noise as reported by some eyewitnesses.
They may have heard main rotor blade slap and mistaken it for the sound of mechanical failure.
I assume a drive shaft can break or TR gearbox fail without any audible sound at that distance.
Chilling video to watch.

[Bell_ringer]

In the very beginning of the video, is that just a puff of condensation when they start?

[[email protected]]

Yep, I agree. But they seemed awfully high on the way up when things suddenly went pear shaped, given what I can make out of the height of the obstacles in the take-off path. Perhaps he increased his TDP height on departure because it was at night, in order to compensate for the light into dark scenario and to give him a better chance of flyaway (ironically).

[n5296s]

I don't understand. Just watched the video. The aircraft is rotating clockwise (viewed from above). Surely that's the SAME as the rotor rotation? Or does the 139 have US-style anti-clockwise rotor?

As a medium-time PPL-H I've thought a lot about this accident (like everyone else :-( ). I guess if you lose the TR at low altitude like this, you're pointing where you're pointing (even if you bring the yaw under control) and going where you're going. At altitude you can turn with cyclic, but no time for that here. So unless you have exceptionally good luck, it's not going to end well.

[jeepys]

Yes the 139 and 169 (this was a 169) have a counter clockwise rotor.

[ShyTorque]

The YouTube video shows what appears to be a normal Class 1 helipad departure followed by a tail rotor drive failure.

The aircraft was flown in a controlled manner to altitude but then yawed slightly to the right. There was a slight pause, then a more rapid yaw set in. Typical for that sort of a failure.

[[email protected]]

n5296s - you need speed to retain directional control without the TR and, if you haven't got any speed, you need a lot of height to dive on that speed - he had neither!

If you have ever seen the video of the Wessex going into a Welsh lake many years ago - a colleague of mine was flying it and he had the failure at 60 kts and 1000' - he still ended up in a horrendous spiral descent.

jumpseater - I'd be very surprised if it was disorientation but less surprised if it was a medical issue.

[DOUBLE BOGEY]

I hesitate to say this, but if it is a TR Drive/Low power Hard over, he seems to take a long time to react. Many rotations under near hover power before the descent takes place.

[DOUBLE BOGEY]

CRAB in the Wessex event, did he keep the power on and cushion into the lake?

[Simplythebeast]

Link to video of the Wessex accident at Llyn Padarn in August 1993.
https://youtu.be/cDj6oYaYrR8

[DOUBLE BOGEY]

STB -Thanks for the link. Looks “Power On” Crab are you able to confirm?

[Flying Bull]

If you watch the video you can see something fast going down from the helicopter to the lower left in the video. Seconds after that the turn starts https://cimg7.ibsrv.net/gimg/pprune.org-vbulletin/1513x966/2acfd162_077e_40d1_85fc_c7a153237c2b_161a68ebaf64c1ea9cf9c2c 03b4739abccb6ca32.jpeg
Part from helicopter?

[VintageEngineer]

I was an RAF Engineer Officer involved at the periphery of the Wessex crash.

Attached below is the summary of the accident report.

There are several Youtube videos, just search 'llyn padarn helicopter crash' (I'm too new to post a link here).

[Echo Romeo]

What material are the tail rotor blades made from?

[Geoffersincornwall]

When teaching TR Fail (drive fail or worse) in the 139 sim I first caution the candidates about taking care not to take too much detail away with them after this exercise - the sim cannot be relied upon to truly replicate the real event. In any case, as the UK CAA research has shown, there are a variety of failure modes that result in loss of directional control. There are, however, one or two elements of the training that are worthy of remembering and putting to good use in the event that you do suffer the loss of directional control and it applies throughout the flight phases - take-off, transition and cruise. That vital action is to quickly lower the collective fully. The second vital action is to close down the engines if in transition to facilitate a pitch-pull prior to ground contact. Failure to do this will result in making the situation worse during the 'arrival' at terra firma. In the cruise, you have more options provided you have been quick enough lowering the collective and are not spinning. It's possible to make use of the engine power to reduce RoD if required but by 500 ft the engines should be off. We see a perfect application of these principles when a 139 threw a blade in Macau. It works, but your reaction has to be instantaneous and to condition yourself for such a horrific event you need to practice - a number of times - in a good quality Full FLight Sim. If the loss of directional control occurs in the hover just lower the collective immediately an close down the engines after you are safely down.
G

[Simplythebeast]

Looking at that, I dont think it is something off the helicopter. It is travelling much too fast and more likely to be something flying past or being blown past, much closer to the camera.

[Old Farang]

I hesitate to say this, but if it is a TR Drive/Low power Hard over, he seems to take a long time to react. Many rotations under near hover power before the descent takes place.
This has been bothering me also. I have not flown helicopters for years, and the old things that I used to flap around in did not have such luxuries as an auto pilot, in fact I thought it was the latest thing when one of them had electric cyclic trim.
But it has been posted by people that should know that the A/P would probably be engaged, at least in attitude mode. The way that thing spun around it is almost like it was being driven. Surely, such an experienced pilot would have had the collective down long before the spin developed to the extent shown on the video. Is it possible that this is related to switching the A/P to full authority, or whatever the change is called, as he started to transition?

[jeepys]

The autopilot will only have max 10% authority.

[Unregistered_]

As someone else suggested earlier, but now I can't find it, it looks to me like they possibly climbed vertically and backwards then attempted rotation - with a reasonable tailwind.
Had something let go at that power setting in essentially an OGE hover, the immediate 'snap rotations' would be more evident I would have thought. The rotations came on relatively slowly I thought - consistent with running out of T/R authority. Started spinning with no T/R authority - dumped the collective and never recovered.
Did we get an answer how a potentially heavy AW169 behaves in a high power OGE downwind hover?

[GeeRam]

Looking at that, I dont think it is something off the helicopter. It is travelling much too fast and more likely to be something flying past or being blown past, much closer to the camera.

I don't think it's an object at all, looks to be light reflection/refraction on the lens as the camera tracks up into the stadium lights...?

[Old Farang]

The autopilot will only have max 10% authority.
Ok, assuming that it is not faulty.

[Nige321]

If you watch the video you can see something fast going down from the helicopter to the lower left in the video. Seconds after that the turn starts https://cimg7.ibsrv.net/gimg/pprune.org-vbulletin/1513x966/2acfd162_077e_40d1_85fc_c7a153237c2b_161a68ebaf64c1ea9cf9c2c 03b4739abccb6ca32.jpeg
Part from helicopter?




It's an insect lit by the stadium lights. Another at 1:02. You see them all the time on CCTV. Really annoying when they trigger motion sensors to start recording... Already discussed...

[strake]

It's an insect lit by the stadium lights.

Playing that video at quarter speed, I respectfully disagree. The insects on my CCTV don't behave in that manner and there is always more of them. That 'particle' initially appears suddenly at 46.2s at the back of the aircraft, disappears for less than 100th of a second then appears again moving at speed to the left and down. Looking at what is happening to the aircraft and admittedly drawing a speculative conclusion of where the problem might lie, one has to question the odds of a lone insect appearing to fly across the screen emanating from that position at that exact time?

[Slowclimb]

As someone else suggested earlier, but now I can't find it, it looks to me like they possibly climbed vertically and backwards then attempted rotation - with a reasonable tailwind.
Had something let go at that power setting in essentially an OGE hover, the immediate 'snap rotations' would be more evident I would have thought. The rotations came on relatively slowly I thought - consistent with running out of T/R authority. Started spinning with no T/R authority - dumped the collective and never recovered.
Did we get an answer how a potentially heavy AW169 behaves in a high power OGE downwind hover?

The aircraft had a headwind. It was pointing north, in a northerly wind.

There was a brisk low-level flow on Saturday evening; I’m sure part of the reason for the highish climb was to clear all the shear before transitioning.

[dmba]

I assume they scoured the pitch for any parts that might have fallen?

[Nige321]

Playing that video at quarter speed, I respectfully disagree. The insects on my CCTV don't behave in that manner and there is always more of them. That 'particle' initially appears suddenly at 46.2s at the back of the aircraft, disappears for less than 100th of a second then appears again moving at speed to the left and down. Looking at what is happening to the aircraft and admittedly drawing a speculative conclusion of where the problem might lie, one has to question the odds of a lone insect appearing to fly across the screen emanating from that position at that exact time?

Have it your way.
Insects on my night time CCTV ALWAYS act like that.
I just stepped through the frames, blobs of light at 0.52, 0.53, 0.57, 1.02, 1.05, 1.06
Some of them flitting in all directions...

[strake]

Have it your way.

Please understand, I mean no disrespect to anyone's views, it's just an observation.

[XN593]

In the YouTube video the anti-collision light is clearly visible as are it's reflections under the main rotors. As control is lost the light seems to extinguish. Is it just me and my phone?

[Slowclimb]

The speck moves too fast to be anything but an insect in the foreground. Its sudden appearance could’ve been when it flew into the light cone from the floods, or simply near enough to the camera to be seen.

Some observations; after just the first half of rotation, it looks like the rotation was so rapid the resulting g-forces would’ve made positive control extremely difficult. Also, the aircraft rapidly built up a very high rate of descent. So thrust was lost from the main rotor one way or another.

It looks like the transition was above 300’, so sound would have been at least a second behind what you see.

[Fareastdriver]

Surely, such an experienced pilot would have had the collective down long before the spin developed to the extent shown on the video.

Here is a cameraman's last shot taken in 1960. Later on an external shot shows you what happened.

How fast are your reactions to a tail rotor failure at low speed.

https://www.youtube.com/watch?v=HvTbgz_Cxw8

That was at about 1,000ft. Try it at 300.

[aox]

It looks like the transition was above 300’, so sound would have been at least a second behind what you see.
speed of sound about 330 metres per second, not feet

[stagger]

It moves too quickly and if it was part of a blade it would have embedded itself into the grass on the pitch and suspect it would have already been mentioned in the media if that was the case. As there are many similar light flashes throughout the video, I would say these are probably insects.

When thinking about what these specks might be - it is worth noting that this didn't happen during summer. It was a dark, cold evening - you won't find too many insects flying around in these conditions.

[Pittsextra]

Saw this & final report..

https://www.youtube.com/watch?v=N6vWraEkVkY

https://www.fomento.gob.es/recursos_mfom/2007_boletin_03.pdf

[Nige321]

When thinking about what these specks might be - it is worth noting that this didn't happen during summer. It was a dark, cold evening - you won't find too many insects flying around in these conditions.

So why is my CCTV motion detection triggered all night long by... Insects...

[ShyTorque]

I hesitate to say this, but if it is a TR Drive/Low power Hard over, he seems to take a long time to react. Many rotations under near hover power before the descent takes place.

Have you personally experienced this particular failure, or practiced it in a simulator? Thirty years ago I was a QHI involved in a full motion helicopter simulator project for the UK military and was part of a team (of two) tasked to expand the then current teaching on tail rotor malfunctions, which was woefully inadequate. We did some practical test flying (hours costed by MOD on behalf of Boscombe Down) and developed a syllabus. We then began teaching both "ab initio" and experienced squadron pilots alike. I saw many highly experienced pilots fail to arrest the yaw rate in time, despite being pre-briefed and pre-warned that the T/R was about to malfunction. Bear in mind that this was in a simulator lesson doing nothing but tail rotor malfunctions.

Given that it takes a second or two to diagnose the failure in the real case, the pilot probably did as well as anyone could have in the circumstances. Note the slight pause in the yaw rate - it's likely that full opposite pedal was applied in an attempt to stop the yaw, probably a pilot response.Then once the tail rotor blades produced no more effective thrust, round it went again at an increased rate of yaw. Once a rapid fuselage spin develops, response to cyclic inputs may not be what is normally expected and that effective rotor rpm is reduced.

Other things that could cause a sudden yaw are a gust of wind, an autopilot/SAS malfunction, or an inadvertent foot touching a yaw pedal. Dumping the lever and chopping the engines would be an inappropriate immediate response.

This unfortunate pilot probably experienced a T/R drive failure at the most critical stage of flight imaginable. I say "probably" because AAIB haven't yet released initial findings and I am quite possibly wrong; obviously I'm only an amateur compared to some experts here.

[jeepys]

[QUOTE=Pittsextra;10297639]Saw this & final report..

https://www.youtube.com/watch?v=N6vWraEkVkY

https://www.fomento.gob.es/recursos_mfom/2007_boletin_03.pdf[/QUOTE

Does it mention in the report TR failure?

[[email protected]]

STB -Thanks for the link. Looks “Power On” Crab are you able to confirm? DB - you can see the rate of rotation slow at about 300' whuich is when he speed selected the engines to idle - he said the most difficult thing was judging at what height to cushion the touchdown, he said he did it a bit too high - I think he did a pretty good job since most on board survived but it was unfortunate that it went in slightly backwards with about a 25g impact.

Stagger - It was a dark, cold evening - you won't find too many insects flying around in these conditions. except around hot, bright stadium lights......

[Pittsextra]

[QUOTE=Pittsextra;10297639]Saw this & final report..

https://www.youtube.com/watch?v=N6vWraEkVkY

https://www.fomento.gob.es/recursos_mfom/2007_boletin_03.pdf[/QUOTE

Does it mention in the report TR failure?

No LTE. You can read the report in English towards the rear of the bulletin. There are of course other contributory factors but like is so often the case unless you are internal to the daily ops you only find out how people are living after these kind of accidents. Who knows if this Spanish accident is relevant but it does seem to have quite a few similarities?

[helimutt]

If you watch the video you can see something fast going down from the helicopter to the lower left in the video. Seconds after that the turn starts https://cimg7.ibsrv.net/gimg/pprune.org-vbulletin/1513x966/2acfd162_077e_40d1_85fc_c7a153237c2b_161a68ebaf64c1ea9cf9c2c 03b4739abccb6ca32.jpeg
Part from helicopter?



watch the clip carefully then a repetitive playback of just at what I believe to be TDP at around 53-56 seconds. not this earlier one. watch carefully in the top left corner of the picture. then take a look at the photos in the newspapers of one of the three tail rotor blades which looks ripped off. is that the blade departing?

[ShyTorque]

I was an RAF Engineer Officer involved at the periphery of the Wessex crash.

Attached below is the summary of the accident report.

There are several Youtube videos, just search 'llyn padarn helicopter crash' (I'm too new to post a link here).

It's notable that RAF Wessex crews at that time had no simulator training.

[strake]

except around hot, bright stadium lights......

Which are about 20 metres up from the camera position..so that insect would have to be rather large...I just find it a strange coincidence that from all the available space on the screen image, a bug appears to fly out from where the TR is located.

watch carefully in the top left corner of the picture.

It does indeed appear to be from the same trajectory as the first quick movement across the screen.

However as has been pointed out, one would have thought that by now, there would have been reports of debris landing in the stadium.

[KarlADrage]

watch the clip carefully then a repetitive playback of just at what I believe to be TDP at around 53-56 seconds. not this earlier one. watch carefully in the top left corner of the picture. then take a look at the photos in the newspapers of one of the three tail rotor blades which looks ripped off. is that the blade departing?
When you play it back at quarter speed you can see it turn through nearly 90 degrees before exiting the top of the frame. Like Nige, I am firmly in the bug camp.

[monkey_see]

In the YouTube video the anti-collision light is clearly visible as are it's reflections under the main rotors. As control is lost the light seems to extinguish. Is it just me and my phone?

The anticoll on the AW169 sits on a main bus which is shed during double generator failure.

[GrayHorizonsHeli]

watch the clip carefully then a repetitive playback of just at what I believe to be TDP at around 53-56 seconds. not this earlier one. watch carefully in the top left corner of the picture. then take a look at the photos in the newspapers of one of the three tail rotor blades which looks ripped off. is that the blade departing?


the third blade is likely burnt from the fire, but the wait and see camp wont want to hear that until some form of scientific testing is completed in 2030.

[helicrazi]

Another expert has been wheeled out

https://www.bbc.co.uk/news/uk-england-leicestershire-46044277

near vertical apparently as he wanted forward speed??? I hang my head in shame...

[dukiematic]

Learmount. For it is he....

[SASless]

A for what it is worth.....in this video....a Sikorsky S-58T lifting an AirCon from a RoofTop suffers a Tail Rotor Drive failure.....memory serves me the drive shaft couplings stripped causing the loss of drive with no components departing the aircraft.

I talked with the Pilot shortly after the event and he said he jettisoned the load and began to maneuver the aircraft towards a safe landing area and upon getting to a point he thought he could make an autorotation....he cut the engines.

When he lowered the nose to gain some airspeed to be able to flare.....is when it went all wrong.

He was genuinely remorseful when he said he regretted not being able to save the aircraft.

https://www.youtube.com/watch?v=5kXUZQYFu18

[Torquetalk]

Without any implication with respect to the current accident, the pilot in the Wessex Welsh lake video seems to have done an outstanding job given the circumstances. Looks as though they managed to check some of the yaw and get some directional control before accepting more yaw and a reduced ROD and forward speed.

All the videos all show that once the yaw has accelerated following a serious anti-torque problem, stopping it is going to be extremely difficult, even with a lot of height.

[airsound]

Another expert has been wheeled out

It's not just another expert, helicrazi. As dukiematic says, it's Learmount (David). And you might not know, but the Honourable Company of Air Pilots (used to be GAPAN) has just given him its Award for Aviation Journalism.

airsound

[Echo Romeo]

Learmount.....:ugh:

[Sir Niall Dementia]

Learmount, nearly as bad as Jim Ferguson, sadly with slightly more media street cred.

SND

[runway30]

I’m not defending Learmount but as someone who has done his fair share of punditry let me tell you what the media is looking for. They want a very complicated subject explained in two minutes in a way that 99% of the population will understand. This is while, depending on where you are being interviewed, someone is talking in your ear and you’re trying not to think of how many million are listening to you making an ar*e of yourself. Not as easy as you think.

[Echo Romeo]

The fast moving spec seen at 46 sec is, Imo, not a part of the aircraft. However the falling object appearing on the left at 54 sec's and disappearing into the floodlight glare at 58 is of more interest.

[TeeS]

The autopilot will only have max 10% authority.

Hi Jeep’s
An autopilot with only 10% authority wouldn’t be much use as an autopilot. Individual series actuators typically have 10-15% authority with two actuators in series giving 30% (ish), this is then usually extended to 100% authority by use of parallel actuators. I totally agree an actuator runaway will be limited by its authority.
I‘m not suggesting any of this is relevant in this case.
Cheers TeeS

[Torquetalk]

Without any implication with respect to the current accident, the pilot in the Wessex Welsh lake video seems to have done an outstanding job given the circumstances. Looks as though they managed to check some of the yaw and get some directional control before accepting more yaw and a reduced ROD and forward speed.

All the videos all show that once the yaw has accelerated following a serious anti-torque problem, stopping it is going to be extremely difficult, even with a lot of height.

Aircraft type would also appear to play an important role in the rate of yaw development and prospects for recovery. The lake and hoist videos show quite rapid yaw arrest in response to control inputs. It makes me wonder if some aircraft are harder to get back, with the AW139 & AW169 more at that end of the spectrum.

[RiSq]

Just worth noting that I know someone who was still at the game and has been to several and seen the helicopter take off.

apparently, it was all normal (including that first initial yaw input when it first looks controlled). You cannot make it out too well in the video, but the gear retracts and it begins a rotation - apparently as it always did.. At that point it never seems to recover.

im no expert and could be coincidence - but could that suggest a peddle / input problem. He stated that it actually didn’t sound too out of the ordinary. The strange noise people seem to be referring to from what he saw was the pitch of the blades against the air as it began to rotate seemingly uncontrollably.

just thought I’d share to maybe shed some insight from someone who has some basic understanding of aircraft / rotors rather than just a regular member of the public.

it maybe a result of the cause rather than the cause itself, but thought I’d share it with people much more knowledgeable than myself.

[sycamore]

I ,can say that if a rotor blade departs,then the remaining blades and gearbox will have departed too; this will likely take the Cof G past the nose,and the stick fully back...

[Arezzo99]

Have you personally experienced this particular failure, or practiced it in a simulator? Thirty years ago I was a QHI involved in a full motion helicopter simulator project for the UK military and was part of a team (of two) tasked to expand the then current teaching on tail rotor malfunctions, which was woefully inadequate. We did some practical test flying (hours costed by MOD on behalf of Boscombe Down) and developed a syllabus. We then began teaching both "ab initio" and experienced squadron pilots alike. I saw many highly experienced pilots fail to arrest the yaw rate in time, despite being pre-briefed and pre-warned that the T/R was about to malfunction. Bear in mind that this was in a simulator lesson doing nothing but tail rotor malfunctions.

Given that it takes a second or two to diagnose the failure in the real case, the pilot probably did as well as anyone could have in the circumstances. Note the slight pause in the yaw rate - it's likely that full opposite pedal was applied in an attempt to stop the yaw, probably a pilot response.Then once the tail rotor blades produced no more effective thrust, round it went again at an increased rate of yaw. Once a rapid fuselage spin develops, response to cyclic inputs may not be what is normally expected and that effective rotor rpm is reduced.

Other things that could cause a sudden yaw are a gust of wind, an autopilot/SAS malfunction, or an inadvertent foot touching a yaw pedal. Dumping the lever and chopping the engines would be an inappropriate immediate response.

This unfortunate pilot probably experienced a T/R drive failure at the most critical stage of flight imaginable. I say "probably" because AAIB haven't yet released initial findings and I am quite possibly wrong; obviously I'm only an amateur compared to some experts here.

An fascinating post from a QHI experienced in Tail Rotor failures in the sim.
In what follows I assume it was a tail rotor failure and the usual caveats to hasty judgement apply.
If I'm reading you correctly and not reading too much between the lines your sim experience tells you if you really do have a tail rotor failure, tail rotor control failure or failure in the drive train to the tail rotor by the time the handling pilot has evaluated all cues and eliminated other malfunctions; yaw trim actuator hard over, other pilots boots, or whatever then the situation is perilously close or already beyond effective recovery action. Put simply if you have a tail rotor failure especially at high power settings with low air speed, zero weathercock stability, then the collective lever has got to lowered immediately and swiftly, how long a second, two at the outside. Then given the T/O flight profile the nose must be lowered aggressively to recover airspeed for flare, check level. Do Flight Manuals even have graphs for this nightmare?

[Nige321]

Another 'expert' who should know better...

Tony Cable (https://www.dailymail.co.uk/news/article-6338137/Helicopter-disaster-killed-Leicester-City-owner-sparked-major-failure-tail-rotor.html)

Tony Cable, a former senior investigator at the Air Accident Investigations Branch (AAIB), has watched footage and said: 'The takeoff looked normal but as it hovered above the stadium you can see pieces falling away. It looks like from the rear rotor blades.'It is consistent with a tail rotor breaking off. There are lots of pieces flying around. If you lose a large proportion of the blade you get a very large imbalance and pull the whole tail rotor off the aircraft'.

[Art of flight]

The significance of the anti collision light extinguishing in the video could be a sign of both generators going off line, this could be due to both engines being shut down, in turn suggesting the pilot shut them down in reaction to a tail rotor drive failure? Speculation on my part following a logical chain of events if the anti coll was extinguished.

[clareprop]

Another 'expert' who should know better...

Why? You think they're insects, he thinks they're pieces of tail rotor.

[gulliBell]

When teaching TR Fail (drive fail or worse) in the 139 sim I first caution the candidates about taking care not to take too much detail away with them after this exercise - the sim cannot be relied upon to truly replicate the real event. ...

etc etc Yep, I agree with all of that, 100%.

[unknown.mp3]

The anti-collision light mounted on top of the vertical fin is still flashing. You can see it still flashing as it disappears behind the stadium.

[FlightSpanner]

Surely the time between seeing the so called object and the loss of control is way too long, would be instant.

His interview on Sky is shocking, implying that a simple lowering of the collective and cutting engines would have quickly brought the aircraft under control! He has either been seriously misquoted or lost the plot!

[clareprop]

He has either been seriously misquoted

​​​​​​​Given his credentials and it's Sky, I'm guessing he's been seriously misquoted....but maybe experts here know better....
Tony Cable:
B.Sc., M.R.Ae.S
University of London BSc Honours Degree in Aeronautical Engineering
Powerplant Design Engineer with Boeing Aircraft on large public transports
Systems and Safety Engineer with BAe, including Tornado and Concorde
Aircraft Engineering Accident Investigator full-time since 1976
Visiting Fellow at Cranfield University

[Nige321]

Why? You think they're insects, he thinks they're pieces of tail rotor.

Surely he should know better than to pronounce the cause of the accident from a Sun video...

And a cursory glance at the wreckage shows the tail rotor roughly where it should be, albeit sans half of one blade.
Surely the imbalance of losing half a blade would have put the TRGB somewhere in the next county...?

[GrayHorizonsHeli]

The significance of the anti collision light extinguishing in the video could be a sign of both generators going off line, this could be due to both engines being shut down, in turn suggesting the pilot shut them down in reaction to a tail rotor drive failure? Speculation on my part following a logical chain of events if the anti coll was extinguished.

doesnt the battery kick back in and supply power at that point?

[Nadar]

I'm amazed by the low quality of the (Sun) video, and I've assumed that they have a higher quality version but have opted to share a highly compressed version online. The sun has now updated their video (https://www.thesun.co.uk/news/7626307/horror-footage-proves-leicester-city-helicopter-pilot-was-a-hero-says-air-expert-who-claims-tail-rotor-caused-fatal-plunge/) (watch from 1:18) where they replay the "interesting" part in slow motion.

I now doubt that they have a higher quality version, as I think they would have used that as the source for the replay. It's a shame, because it would have made it much easier to tell

[clareprop]

Surely he should know better than to pronounce the cause of the accident from a Sun video...

Evidence is evidence no matter where it comes from. Given he was a senior guy with the AAIB engineering section for 40+ years and during that time investigated many infamous rotary accidents, I'm thinking that he probably still has the odd chat with them from time-to-time.

[gulliBell]

Unburnt fuel, oil or water.

The change in direction of the rising puff of smoke from the engine whilst it was being started suggests to me the initial climb was with a tail wind....granted, maybe the wind was swirling inside the stadium but that smoke did catch a bit of tail wind...I don't think it was sucked in to some inflow into the rotor disc as the rotor had only just started to turn.

I'm still suspicious about that smoke...perhaps caused by oil momentarily getting past a labyrinth seal and burning in the hot engine? I'm not familiar with that particular engine, but it does look unusual.

[ShyTorque]

I’m not defending Learmount but as someone who has done his fair share of punditry let me tell you what the media is looking for. They want a very complicated subject explained in two minutes in a way that 99% of the population will understand. This is while, depending on where you are being interviewed, someone is talking in your ear and you’re trying not to think of how many million are listening to you making an ar*e of yourself. Not as easy as you think.

Exactly! Speaking as someone who has been approached by the media to appear in such interviews, thought about it and declined, he does have my sympathy - especially as his personal experience was as a fixed wing pilot. One small slip of the tongue in the harsh spotlight of the media and you'll be pilloried here forever!

[VintageEngineer]

As a former helicopter maintenance engineer, I can confidently say that if an AW169 lost a tail rotor blade then the gearbox will rapidly break free and depart from the airframe.
Helicopters with 4-bladed tail rotors might, with luck, throw the opposite blade too, thus putting the rotor back into some form of balance, but a 3-bladed tail rotor has no chance.
The pictures I have seen suggest that a tail rotor blade loss is highly unlikely to be the cause of this accident.

[tqmatch]

I'm still suspicious about that smoke...perhaps caused by oil momentarily getting past a labyrinth seal and burning in the hot engine? I'm not familiar with that particular engine, but it does look unusual.

The smoke coming from the engine is nothing to be concerned about, if engineers got twitchy every time we saw a start with white smoke, none of us would ever go flying! It's too thick and too soon in the start cycle to be oil, it is almost certainly fuel - perhaps unburnt from the last shutdown being kicked out, or a small purge coming through prior to the ignitors cracking off, but most certainly not an issue to flight safety

[Art of flight]

doesnt the battery kick back in and supply power at that point?
Once DC buss 1&2 are lost the battery will power some essential services. The essential services busses can be used, but with limited systems, the anti coll is not on the list.. A rate of decent around 2500 feet per minute would give around six seconds before impact from that height, so not much time to do anything other than get the engines to off, not even time to get the switch made to get the gear down.

[[email protected]]

Looking at the latest Sun video, it looks like the 'object' approaches the rotor disc from behind, hits it and is spat downwards.......

[GEOALI195]

Not insinuating or inferring anything here-merely an observation. I've watched the Sun video several times, paused it and tried (as best as possible) to advance it frame by frame. At 1.20 and 2 or 3 tenths (at a guess), just outside the red circle at about 3 o'clock, is a white dot which then enters the red circle seemingly heading towards the tail. That same white "dot" then seems to be spat out initially to the right but them starts heading rapidly across the screen right to left. At first I was convinced it was just an insect flying close to the camera but now I'm not so sure. What started as a dot now seems to become a very regular (rectangular) shape as it travels across the screen

[clareprop]

Hang on, last time everyone looked, it was an insect :D

[Beardedtunapilot]

Not insinuating or inferring anything here-merely an observation. I've watched the Sun video several times, paused it and tried (as best as possible) to advance it frame by frame. At 1.20 and 2 or 3 tenths (at a guess), just outside the red circle at about 3 o'clock, is a white dot which then enters the red circle seemingly heading towards the tail. That same white "dot" then seems to be spat out initially to the right but them starts heading rapidly across the screen right to left. At first I was convinced it was just an insect flying close to the camera but now I'm not so sure. What started as a dot now seems to become a very regular (rectangular) shape as it travels across the screen


Birdstrike, a white drone( DJI )..? In that case he would seemingly be downwind since its "spat" downwards and left in screen...?

[DOUBLE BOGEY]

SHYTORQUE "Have you personally experienced this particular failure, or practiced it in a simulator?"

Hi Shy the answer is no, thankfully. For the FSTD yes, quite a bit. Actually just in the last weeks as part of my TRI/TRE revalidations. However, I have not tried TR failures at the top of TDP as the general wisdom would concur, its probably not going to end well. However, in my day job we are in this position on every take-off. VTOL Helipad variable TDP.

You will know the heavy emphasis in EASA land for the promotion of "Startle Effect" and "Resilience" training. The idea being that sound techniques, practiced slowly and deliberately, leading to multiple events in other phases of the training with decreasing notice and increasing distraction in an attempt to over come the "Startle" (I think we used to call this "Over arousal") and build resilience. I but into this and spend a lot of time with candidates/students doing TR failures and Autos. However, up to now, I have ignored this particular trajectory for the TR stuff.

I guess my real point is, does any us feel there is an acceptable solution in the average MEH for a TR drive failure close to VTOL TDP?

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?

[malabo]

Don't despair at what you can/can't/imagine to see. The posted Sun video quality isn't as good as their frame photos, so there could be posters/commentators with a better visuals than the unwashed on which to base their comments.

Double Bogey, I teach the same, but there is a technology shift that we have to adapt to: older helicopters had throttles on the collective, instant off and instant (relatively) stop of rotation. All new helicopters have remote throttles you can't reach, and dumping the collective is a crude tool that only takes away part of the torque.

[KarlADrage]

I'm still not at all convinced that it's anywhere near the helicopter at any stage. Granted, it does fly right out of where the cab sits in the frame, but I think that's just pure coincidence.

Whatever it is will almost certainly have been elongated in the video because of the slow shutter speed being used on the camera (on account of it being dark above the stadium) and the speed of travel of the object (which if you assume it to have originated from the helicopter must be somewhere in the ballpark of 300mph!).

[dmba]

A paused frame can be said to look like almost anything with a white blob on it.

The context is various white blobs, some moving across, some up, some down, some back and forth...even while the a/c moves over beyond the stadium...They're bugs..

[strake]

Granted, it does fly right out of where the cab sits in the frame, but I think that's just pure coincidence.

As I mentioned above, I think that it is just too much coincidence for an 'insect' to appear to come out of the exact point you would expect if there was a problem with the TR. Yes there are some other light 'flutterings' in the video but nothing like that and I also don't think the camera is focused to give the CCTV type insect images we often see . Given the statement from Tony Cable, I'm pretty much convinced that is something from the TR area letting go. As someone else wrote, it's unlikely he would have said that without some inside knowledge so I guess we'll know soon enough.

[Bell_ringer]

When eventually the facts are known, it is unlikely that the cause will be anything other than something that has happened before.
This is a very public accident which will sadly reinforce a poor perception that helicopter flying is dangerous.
Hopefully everyone commenting and reading will bear that in mind and remember the incredible things that could not be achieved without rotorcraft, the vast majority of which goes by safely and unnoticed.

[KarlADrage]

As I mentioned above, I think that it is just too much coincidence for an 'insect' to appear to come out of the exact point you would expect if there was a problem with the TR. Yes there are some other light 'flutterings' in the video but nothing like that and I also don't think the camera is focused to give the CCTV type insect images we often see . Given the statement from Tony Cable, I'm pretty much convinced that is something from the TR area letting go. As someone else wrote, it's unlikely he would have said that without some inside knowledge so I guess we'll know soon enough.
As crab@ points out, if you are not of the opinion that it's just a bug, you have to concede that whatever it is initially appears behind the helicopter, so is unlikely to be anything letting go from the TR area? I doubt there are too many at this stage not expecting the accident to be related to some kind of TR failure....

[SASless]

In the Bell 412 Sim, while training a very large metropolitan police force's aviation section, at their insistence we experimented with several interesting scenario's involving Tail Rotor failures of all kinds, main drive shaft failures, and even broken MR Pitch link failures at various hover heights .

Some were very high AGL as there are some very tall buildings in that particular city.

The interest was due to their doing various kinds of work involving hovering, hoisting/winching, and fixed line hauls of tactical personnel.

The 412 has an advantage....collective mounted hand throttles which aided in the Pilot being able to move the Collective AND simultaneously roll off the Engine RPM.

Knowing the failure was coming certainly added to the success rate in achieving a good outcome.

Height above ground, Indicated airspeed in the hover, and aircraft gross weight also played a role.

Not knowing the failure was coming and also not knowing what the failure was played a strong role in reducing the positive outcomes....but after a lot of training time....the outcomes were better than when experienced on the first flight where failures were random and a surprise.

The thing to remember....Simulators are just that....Engineers best guesses as to how the actual aircraft will react.

Some critical failures require very quick and exactly appropriate reactions....delay or apply the wrong technique and it does not end well.



I watched a TRE/IRE follow his company's SOP and kill himself (in the sim thankfully) due to the Emergency Checklist and SOP being incorrectly written.

He had been advised of the problem with his Company's procedures and copped a very arrogant and rude attitude and insisted the matter was not up for discussion.

Nothing had to be said in the long drawn out bit of silence as we waited for the Sim to restore itself.

His hat size reduction was only temporary as it is with those kinds of folks.

An observation: Question was raised about stowing the landing gear......why not leave the Landing Gear down until established on your Climb out at Vbroc AND a safe height?

As to holding the Collective and living with the rotation during a Tail Rotor failure at a Hover.....plainly does not fully understand how quickly the rotation accelerates while doing that.

To discuss the better procedure to follow has a lot to do with what Type and Model aircraft that is involved.

Bell products with Collective mounted motorcycle style hand throttles....simply rolling the throttle(s) off and doing a hovering autorotation can be the exact right thing to do.

But that does not work for all tail rotor failures in the hover or very slow speed across the ground.

[Simplythebeast]

When thinking about what these specks might be - it is worth noting that this didn't happen during summer. It was a dark, cold evening - you won't find too many insects flying around in these conditions.
plenty of leaves though and lots of air moving around the stadium due to the presence of a departing helicopter.

[Lonewolf_50]

hmmm i dunno...a spiralling out of control helicopter that appears to not hit a thing on its departure??? something somewhere had to have happened.
Got it. Wild guess. Having reviewed John E's video posting(reposting?) I reserve judgment for a variety of reasons, not the least of which is lack of familiarity with that particular model, the local area around the stadium where this flight took place, and no idea of what the load out was. (Full bag of gas or not? etc).
But again, I digress, could have just as easily been a sleepy mechanic not torquing the bolts correctly.
Maybe. I hope not, but it has happened before.
I see lots of things on the pictures and videos that pique my interest.
Me too. But I chose not to leap to conclusions.
What I had hoped in asking that question of you was, since I had a hard time singling anything out in the videos (posted) available to examine, that you had seen something that I had not and could have explained that to me. leave the thread and don't come back. You are invited to do likewise if you can't answer my question with a bit more civility.
Having flown helicopters, taught helicopter flying, and having had the opportunity to participate in accident investigations (fatal and not fatal) my interest is professional, not that of a gadfly. As you claim to be involved in maintenance, I can appreciate your interest as well.
The amount of misinformation (and in one case, possible slander or libel) posted during the discussion is disappointing.

[GrayHorizonsHeli]

LoneWolf,

unfortunately public forums will never stop with misinformation, thats an impossible task.
everyone is entitled to their opinion, experienced or otherwise.

it is hard to distinguish a persons demeanour thru written words, and if I misunderstood yours, I apologize. I too seek the truth of what happened, everything in the middle of that process is an exercise in patience. I will always participate, even if i end up being wrong.

[212man]

The amount of misinformation (and in one case, possible slander or libel) posted during the discussion is disappointing

thats an understatement! I can hardly bear to visit this thread. I’ve never seen such bollocks!!!

[Livesinafield]

Ok, I find this forum amazing at provinding information on various accidents that i am interested in when the news outlets "get bored" of reporting information, I follow all the accidents and incidents on here for information from fellow pilots, there is much rumor but everyone is entiltled to speculate on what happed just use your judgement to pick out the bits you feel are key and filter out the "opinions" that you decide are no so.

There is lots of speculation and hear say but thats the world we live in... our papers and news outlets are just as bad on different subjects.

I am a fixed wing pilot and have zero helo knowledge but its been nice to read and learn from heli pilots on here all the various details of heli ops ( i never knew a heli departure was so precise and complex)

Thank you, and RIP and condolences all involved in this terrbile accident

[Lonewolf_50]

I will always participate, even if i end up being wrong. My track record for the past ten years is that I do roughly the same; when we are wrong, we can learn something, sometimes. Cheers.

[Sakabian]

As a man of few words, I fully concur with 212mans’ last sentence.

[Chuck Glider]

Offshore oil & gas drifting up & back is a big no no...
Decades ago I was on the MCP01 rig when a departing helicopter did just that, struck the comms mast and was immediately dumped back on to the helideck. It was several days before it was repaired sufficiently to be flown out but with no passengers on board. All movements on and off were made by surface vessel until the helideck was vacated.

However, I came here looking for insight having just watched a Youtube video of this helicopter departure and spin down. Right at the start of the video there is a huge puff of smoke from the exhaust, quickly whipped away, like an old diesel tractor firing up. Not saying this is connected with this accident but is that normal? Not something I have ever seen before.

[Torquetalk]

However, I came here looking for insight having just watched a Youtube video of this helicopter departure and spin down. Right at the start of the video there is a huge puff of smoke from the exhaust, quickly whipped away, like an old diesel tractor firing up. Not saying this is connected with this accident but is that normal? Not something I have ever seen before.

Post 387 above addresses this

[The Old Fat One]

thats an understatement! I can hardly bear to visit this thread. I’ve never seen such bollocks!!![

It is inevitable that an open internet forum will attract all sorts of nonsense whenever an accident occurs. That does mean such discussion is completely valueless. There are experienced rotor jocks posting here (I am not one such) who make a valued contribution to a subject which hopefully makes all helicopter pilots revisit their own emergency drills etc. The dissemination of accident reports and crew room chatter has always been, and will always be, a vital source of flight safety awareness for the professional aviator.

Guys and girls that fly helicopters, or are learning to fly helicopters, will be able to discern the valuable posts from the obvious "b*****ks" or at least ask questions if they require clarification.

Accident debates often offend somebody or other, it is the nature of things...but in all matters aviation it is important - nay, vital - that they continue. Hopefully, soberly, respectfully and advisedly. But it's the internet and sometimes that's not always going to be the case.

As for journalists stepping by and picking up and printing horse manure...seriously who the heck cares? Surely all educated people know that a large percentage of what is printed these days in newspapers is agenda-led, headline-grabbing codswallop, irrespective of the subject matter. Sure it will influence Joe Public, but that's going to happen regardless of anything that is posted on here.

[BFM]

Dear all, I am SLF but have been flown by experts in such aircraft and have a bit of experience in crash reconstruction. My I start with condolences to all in this tragedy? I have studied the sad Sun video closely, and I am struck by the appearance of the tail anticollision light as the aircraft rotates. There are two clear images of this. In the first, at almost exactly the 1 minute mark, the image is blurred by the spinning tail rotor.
In the second, about 2 seconds later, the tail anticollision light is small and apparently not blurred. Would a suggestion that this was now due to the rate of rotation of the tail rotor having reduced be reasonable?
Regrettably I cannot post my screen captured images as the forum thinks I am trying to post URLs.

[gulliBell]

...and I am struck by the appearance of the tail anticollision light as the aircraft rotates..

The light is not omni-directional, don't assume it's a point source shining equally in all directions. And therefore as the aircraft rotates and pitches etc the light might be blocked on that observational angle by parts of the aircraft, or it just might not shine in a particular direction by design. It's very difficult to drawn any conclusions from the light.

[gulliBell]

..As for journalists stepping by and picking up and printing horse manure...seriously who the heck cares? Surely all educated people know that a large percentage of what is printed these days in newspapers is agenda-led, headline-grabbing codswallop, irrespective of the subject matter. Sure it will influence Joe Public, but that's going to happen regardless of anything that is posted on here.

That's right. Only yesterday Sky News slyly used file vision of an AirAsia plane getting fished out of the Java sea from 2 years ago and fobbed that off as the Lion Air plane that crashed on Monday morning.

[mickjoebill]

For those interested in survivability in a similar accident, I refer to this report into a photo flight where and EC130 from a hover, spun from 220 feet and crashed into sand dunes. Even with the EC crash absorbing seats 3 passengers and pilot perished. There was no fire. The report goes into detail regarding vertical G forces.

https://www.onderzoeksraad.nl/en/onderzoek/1779/helicopter-crashed-during-taking-photographs-eurocopter-ec-130-b4-27-june-2010?s=6C1FC5B6203D31C4EA4F371E5B725A7A690814F2

The crash was recorded on video from a distance so the rate of descent is accurate.
Note that pictures of the wreck show the cabin forward of the seats missing, it appears this was done to remove one of the passengers whose limb was trapped rather than being sliced by rotor impact.

Mjb

[gulliBell]

Post 387 above addresses this

I remain to be convinced by that explanation....I've never seen a PWC engine do that before, and I've seen many many starts over many years (but not on this particular model engine). During the start cycle of this engine do the igniters energize as soon as the starter is engaged? I suspect so, so if that was fuel being blown out the engine I'd expect it to be like a flame thrower and not smoke like. To me that looks like oil smoke, from oil that has leaked past a seal that shouldn't. And leaking seals can turn into bad bearings. And bad bearings can turn into failed engines.

[ShyTorque]

The result of a failed engine would not be as per that seen in the videos. A poor igniter can result in fuel vapour being emitted from the exhaust during the start sequence of many turbine engines - obviously there is more than one igniter.

[G0ULI]

Having viewed all the videos, photos and links on this thread, I am unable to see any obvious external faults with the aircraft or its handling until the turn is initiated while in an effective hover at the top of the ascent.

Given that the engines would have been operating at or close to maximum power in sustaining the hover, is it possible that the effectiveness of the tail rotor was critically reduced just as something distracted the pilot just for a second while the rotation rate increased?

Is there a preferred turn direction? Would the aircraft have survived if the turn had been made in the opposite direction? Is the tail rotor authority sufficient to arrest a spin in either direction while in a high hover?

It seems to me that with no forward velocity, once the aircraft started spinning, there was simply no way to go other than straight down.

[HeliComparator]

White “smoke” on start: I’m surprised by the comments on here. White “smoke” on start is fairly normal and is fuel sprayed out before the igniters have lit it. Seen it often.

[Torquetalk]

I remain to be convinced by that explanation....I've never seen a PWC engine do that before, and I've seen many many starts over many years (but not on this particular model engine). During the start cycle of this engine do the igniters energize as soon as the starter is engaged? I suspect so, so if that was fuel being blown out the engine I'd expect it to be like a flame thrower and not smoke like. To me that looks like oil smoke, from oil that has leaked past a seal that shouldn't. And leaking seals can turn into bad bearings. And bad bearings can turn into failed engines.

It is hard based on what is currently known to see any likely connection between a brief emission from one of the exhausts and what happened afterwards. When I saw it, I thought perhaps coking might have caused it, which was also one of the possibilities suggested in post 387.

[n5296s]

One thing that puzzles me here (and has done in the past)... WHY are the throttles placed in the ceiling, essentially unreachable if you're already in the middle of sorting out an emergency that needs hands on the collective and cyclic? It would make me horribly uncomfortable if I couldn't control the engines at the same time as everything else. The "motorcycle" throttle on the collective just seems such an obviously good idea. I can see a practical problem for a twin (like, needing two throttles) but I'm sure that's not beyond the imagination of man.

[HeliComparator]

One thing that puzzles me here (and has done in the past)... WHY are the throttles placed in the ceiling, essentially unreachable if you're already in the middle of sorting out an emergency that needs hands on the collective and cyclic? It would make me horribly uncomfortable if I couldn't control the engines at the same time as everything else. The "motorcycle" throttle on the collective just seems such an obviously good idea. I can see a practical problem for a twin (like, needing two throttles) but I'm sure that's not beyond the imagination of man.

There are no throttles, only on/off switches. There should be no need to suddenly access the engine controls. In theory...

[gulliBell]

...WHY are the throttles placed in the ceiling...

For helicopters with mechanical plumbing that connects moveable throttles to the engines, it's a simpler installation when the throttles are on the ceiling. But many modern helicopters now just use electrical controls and switches.

[tbtstt]

thats an understatement! I can hardly bear to visit this thread. I’ve never seen such bollocks!!!

It's long been like that on pprune. These crash threads are useful for finding links to external sites, but the conjecture ranges from laughable to infuriating and, in most cases, just demonstrates a spectacular lack of knowledge.

I don't know that many professionals in the industry, but I do know that anyone with an opinion worth listening too wouldn't post anything on here.

[Arkroyal]

My thoughts keep reluctantly focussing on sabotage. Swift removal of TRGB drain plug?
all billionaires cultivate serious enemies.

[flyems]

Could the aircraft have responded in the manner seen on the video as a result of pilot incapacitation?

[rlsbutler]

My thoughts keep reluctantly focussing on sabotage. Swift removal of TRGB drain plug?
all billionaires cultivate serious enemies.

You seem to be the only one - see mine of 30/1902, then #294 now #287 or less.
I hope the police know everyone's name who had access to the aircraft after it arrived at the stadium. I hope the investigators would recognise the signs of noxious products in the cabin.

[anchorhold]

Could the aircraft have responded in the manner seen on the video as a result of pilot incapacitation?

I think that has to be a possibility when faced with an aircraft with less than 300 hrs flight time and a single crew pilot aged 53. This is why the medical requires more frequent ECGs with age. Having said that, an ECG pass, doesn't mean you are not going to be incapacitated by a stroke or heart attack at anytime. That is why it is always better to have two qualified and type rated pilots, which is the case with the queens flight.

[Sir Niall Dementia]

Could the aircraft have responded in the manner seen on the video as a result of pilot incapacitation?


My thoughts keep reluctantly focussing on sabotage. Swift removal of TRGB drain plug?
all billionaires cultivate serious enemies.



Unlikely that incapacitation could cause a reaction like that. and the coroner in the Bournmouth crash seemed to be dreamimg. The ATC tapes that recorded the pilot talking to himself, trying to talk himself out of the loss of control made things fairly clear as to what happened. In fact I belive the ATCO dealing with the flight didn't work for some time due to word she heard.

SND

[tqmatch]

I remain to be convinced by that explanation....I've never seen a PWC engine do that before, and I've seen many many starts over many years (but not on this particular model engine). During the start cycle of this engine do the igniters energize as soon as the starter is engaged? I suspect so, so if that was fuel being blown out the engine I'd expect it to be like a flame thrower and not smoke like. To me that looks like oil smoke, from oil that has leaked past a seal that shouldn't. And leaking seals can turn into bad bearings. And bad bearings can turn into failed engines.

I understand where you are coming from gulliBell - but having watched, watched and watched again I am convinced that is fuel. Admittedly over-fuelling should not occur, even more so with FADEC equipped machines, but it clearly has in this case - now whether it is caused by unburnt fuel from the previous flight, or fuel being introduced too early, I for one cannot speculate as I am not type rated on my engineers ticket on the 169. For the aircraft which I AM engineer type rated, the introduction of fuel in comparison to ignitor activation varies from type to type in some cases from variant to variant. Hell I've seen the same engine installed on different airframes started with different sequences!

What we can deduce is that an engine failure would not normally result in a fully developed torque induced spin as in this case; however I am far more experienced as an engineer than I am as a pilot, so if someone with more flying experience wants to point out why an engine failure would result in a spin, please do so and educate me. A day without learning is a day wasted after all!!

[OldVenturaJockey]

My thoughts keep reluctantly focussing on sabotage. Swift removal of TRGB drain plug?
all billionaires cultivate serious enemies.I live in Leicester just a few miles from where the tragedy occurred. As the various news services have shown an incredible number of people have been involved in the mourning of the enormous loss to Leicester. Minor and major TV, radio and newspapers have actively interviewed helicopter pilots (largely ex-military Lynx pilots) and people involved with Vichai’s various interests. Absolutely nobody has suggested that any foul play/sabotage was involved – there was absolutely no reason. The almost universal guess of the pilots interviewed was that there was a mechanical gearbox failure of some sort at the worst part of Dead Man’s Envelope and that the end was inevitable. I flew Alouettes 55 to 60 years ago and was not allowed to make high vertical departures unless it had been a serious medical emergency that demanded it.

I have recently flown frequently as a helicopter passenger on numerous occasions in both Switzerland and Australia and the pilots would not land if they could not get a good run for take off without high obstruction in front.

[Mike78]

Flyems states.........Could the aircraft have responded in the manner seen on the video as a result of pilot incapacitation?

I think that has to be a possibility when faced with an aircraft with less than 300 hrs flight time and a single crew pilot aged 53. This is why the medical requires more frequent ECGs with age. Having said that, an ECG pass, doesn't mean you are not going to be incapacitated by a stroke or heart attack at anytime. That is why it is always better to have two qualified and type rated pilots, which is the case with the queens flight.

In response to the above, whilst I am not a pilot, I can talk of incapacitation (from experience). As a very healthy and fit 34 year old, with regular medicals, and no history of any heart (or other) conditions, I feinted out of the blue (the first of 134 episodes in a 3 year period). Upon examination, no tests (ecg, tilt table, exercise stress test, repeated holter monitor testing and mri scans) could identify a definite cause - it was clear that this was a transient condition. Only following the implantation of an internal loop recorder, could a problem with my heart be found, or more to the point, the vagus nerve, which exercises a degree of control over blood pressure, which can lead to loss of consciousness. Without the loop recorder testing, there is no way to test for the potential for this condition in any person - no medical will pick this up.

It is far from my place to suggest this type of scenario could be linked to the accident, and in no way would I speculate as to the cause as simply put, I do not have the knowledge required to comment. What I am saying however is that certain conditions can cause an almost instantaneous loss of consciousness, irrespective of how fit or healthy the individual, and no amount of medical testing can rule out such possibilities. What I can also do is describe the sensation when this loss of consciousness occurs, with tunnel vision being the first stage, followed very briefly by intense dizziness and confusion - during such a time, you have very little capacity to action any rational movements or thoughts, particularly the first time, as it is pure confusion.

I do hope that the above wasn't the case, but whatever was the cause, it is a tragic and saddening accident.

[DOUBLE BOGEY]

It's long been like that on pprune. These crash threads are useful for finding links to external sites, but the conjecture ranges from laughable to infuriating and, in most cases, just demonstrates a spectacular lack of knowledge.

I don't know that many professionals in the industry, but I do know that anyone with an opinion worth listening too wouldn't post anything on here.

That would make you wrong. In our industry we have very little opportunity, as professionals and PPLs alike, to learn from each other. PPRUNE provides that forum. Yes some people can sometimes seems spectacularly stupid (me some of the time) and some of us love a good argument. That's "A" Type extroverts for you. But taken as a whole PPRUNE offers an opportunity to learn from each other especially when an accident like this happens.
TBTSST, I do not know what you do, but many on this thread carry out these VTOL departures each time we fly, EMS, HEMS., Police and the Corporate sector. The reason why we have a lot of interest here, is that this failure, in this phase of flight, is theoretically ignored by certification. As such there is very little guidance in Flight Manuals on how to deal with it. There is a reason for that.....if you think about the outcome of this event!
In the end, its up to you if you choose to take part in the discussion or not. However, posing sanctimonious passive aggressive statements, like yours above, means to me you have no value to add at all. So why bother yourself to even visit the thread.

[tbtstt]

That would make you wrong. In our industry we have very little opportunity, as professionals and PPLs alike, to learn from each other. PPRUNE provides that forum. Yes some people can sometimes seems spectacularly stupid (me some of the time) and some of us love a good argument. That's "A" Type extroverts for you...
I am in absolute agreement with you with regards to discussion. This incident has certainly dominated the conversations of all the pilots and engineers I work with this week, as everyone wants to understand what has happened and what can be done to prevent it from happening again...

...But taken as a whole PPRUNE offers an opportunity to learn from each other especially when an accident like this happens.
...on this point we disagree though: Prune certainly offers the chance to learn, but when the conversation is littered with as many (sometimes more) falsehoods than truths I would question the merit of what you could glean from threads like this. There are several aspects of this particular incident that I am clueless about, but given that the responses on here concerning the things I do know about are so mixed there is no way I trust the information concerning something I don't fully understand.

Conversation on incidents such as this between knowledgeable individuals is excellent and absolutely worthwhile, but some of the conclusions reached by supposed professionals in threads like this - while in possession of just a handful of facts - are astonishingly reckless. Based on the available evidence I have my own theory as to what has happened but, until the full story is told, I wouldn't consider making any definite conclusions and I absolutely wouldn't start point fingers at any particular party (and, even with a cursory glance, I can see that has already occurred numerous times throughout this thread).

It certainly wasn't my intention to appear sanctimonious but it is no secret that the media clearly view this forum and threads like this just fuel the nonsense that we see reported on these incidents in the press.

[Torquetalk]

I do hope that the above wasn't the case, but whatever was the cause, it is a tragic and saddening accident.

I hope you got a good solution to the complaint. Relative youth is no guarantee of health, it‘s true. It also appears to be true that although the risk of certain conditions may increase with age, a lot of people are fitter as they age than they were several decades ago (although increasing poverty may reverse that trend overall and in defineable groups). Personally, I like to think of 70 as the new 40 as it‘s good for morale.

That said, I doubt very much if incapacitation will be found to be causal or implicated in this accident. Not only because it is highly unlikely in itself, but also because the pilot was sat next to another person, who although given as a passenger, would almost certainly have been able intervene given their experience and stop matters getting out of hand.

[Torquetalk]

The problem is this:

I don't know that many professionals in the industry, but I do know that anyone with an opinion worth listening too wouldn't post anything on here.

It simply isn’t true. There quite a number of people on here who are both highly experienced, knowledgable and who make valuable contributions to this and other discussions. It isn’t hard to spot a troll or to distinguish between Carling Black Label and Budvar.

[G0ULI]

I know that the weather at the time would appear to contradict the formation of a vortex ring, but could the explanation be as simple as that? High power vertical slightly reversed climb followed by a turn and drift into a vortex of descending air?

[SASless]

There are quite a few very highly experienced and imminently qualified folks who attend these pages and make very good contributions.

On the other hand there are some who think themselves all of that....but who indict that assumption with nearly every post they make.

The key, as in all things in life, is to be able to pick the good from the bad.

Most folks are able to do that but that ability seems to elude those who just do not get it and continue to post their lame views, ideas, concepts, and boasts of experience.

That at least makes it easy to begin the sorting of the good from the bad.

I may not always agree with the what is being posted by the genuinely qualified but then we all have our own views of matters as this flying thing we share is not an exact science that can be firmly framed in simple text.

Those differences tend to be based upon our individual life experiences flying helicopters, a notion that makes very good sense when considered.

As this is a Forum that includes people from all over the World, most using their second language to communicate, there will sometimes be difficulties in communicating what is intended as compared to what was understood.

Every conversation via Text suffers from such issues and Rotorheads is no different in that regard.

If you post here.....be prepared to corroborate what you say as very often you shall be challenged to do so.

If you object to that....please do not post for you do, at some point your feelings shall certainly be hurt.

[bizjetway]

Both Eric & Izabela (the pilots), followed a plant based diet and regularly exercised. They were healthier than most pilots, so I rule incapacitation out of the equation. Sabotage, something (a bird or drone) hitting the tail rotor or mechanical malfunction is the cause. We will find out soon.

[Magplug]

It has been a few years since I flew heavy helicopters but fundamentally the loss of TR control 200-500 feet above the stadium was not survivable.

The AAIB will want to quickly establish the '4 corners' of the accident to confirm that all the components of the aircraft are present at the crash scene. One video shot seems to suggest that a component flew away from the aircraft with high energy immediately before control was lost, the only components posessing such energy would have been a MR pocket (or two) or a TR blade. The fact that the aircraft immediately lost yaw control indicates it may have been a TR blade.... Crash site pictures indicate 2 TR blades present but one is half missing, you could argue it had been consumed in the post crash fire but the edges appear jagged as if it had been torn apart rather than burnt. The AW 169 has an impeccable safety record with no history of TR blade mishaps or other TR drive or contol problems. So why in this case?

TR blades are stressed in construction so as to survive a minor impact from a birdstrike and still perform their role. In this day and age modern helicopters do not crash because birds fly through the tail rotors. In-service failure due to substandard manufacturing is a possibility but frankly unlikely. It is much more likely that a foreign object struck the tailrotor causing sufficient damage to cause blade failure and separation.... But caused by what? The surrounding area several hundred yards in every direction will be thoroughly searched for debris.... who knows what else might be found?

Might we be looking at the first fatal aviation accident due to an aircraft colliding with a drone?

[SASless]

What does a "Plant based Diet" have to do with the question of "Sudden Incapacitation"?

I also question the suggestion the "Second Pilot" could have handled the situation if it had occurred......just how do we know that?

[DOUBLE BOGEY]

It has been a few years since I flew heavy helicopters but fundamentally the loss of TR control 200-500 feet above the stadium was not survivable.

If you are correct...…..its a depressing and sobering statement!

[SASless]

In general....I would agree with MagPlug about the differences between small and large Helicopters when we talk of Tail Rotor failures.

The forces generated by the Rotor systems on large aircraft create a real design problem for the Engineers designing the aircraft.

How much Tail Fin area does it take to facilitate adequate weather vane effect for those large helicopters?

My trusty old Huey did pretty well.....the Huey Cobra derived from the Huey.....did not.

I would bet my other trusty steed, the Sikorsky S-58T, was far better than the Sikorsky S-61 or CH-53.

As in some other things in life....Size does matter along with technique.

[Torquetalk]

What does a "Plant based Diet" have to do with the question of "Sudden Incapacitation"?

I also question the suggestion the "Second Pilot" could have handled the situation if it had occurred......just how do we know that?

We don’t. But were “passive” incapacitation or annnounced incapacitation involved, I think it’s reasonable to assume that a pilot of her experience would be able to apply control inputs to maintain a safe flight condition.

[dmba]

What does a "Plant based Diet" have to do with the question of "Sudden Incapacitation"?

I also question the suggestion the "Second Pilot" could have handled the situation if it had occurred......just how do we know that?

I can only assume plant eaters will never ever die

[asdf1234]

We don’t. But were “passive” incapacitation or annnounced incapacitation involved, I think it’s reasonable to assume that a pilot of her experience would be able to apply control inputs to maintain a safe flight condition.

It's my understanding that the passenger pilot had a fixed wing licence and not a rotary wing licence .if that is the case, and please correct me if I'm wrong, how would her fixed wing experience help her in a rotary wing environment?

[Gustosomerset]

So speculation as ever but given what has been observed so far it seems most likely that:
a) The aircraft was high enough at the apparent point of failure to avoid hitting the TR on any part of the stadium or other fixed object
b) Therefore the failure was likely caused either by something else airborne hitting it - or some sort of separate mechanical failure

Assuming the mechanical failure option, (in the absence of any clear evidence of another airborne object) one thing that still puzzles me is why the pilot chose to lift to such an apparently unnecessary height before attempting to transition into forward flight. Could it be that he was aware of some sort of anomaly on the lift out that made him want to gain extra altitude to have the option of an autorotation away from the confined space of the take-off site? If there was a problem near the ground he would presumably have just put it straight back down - so whatever it was presumably occurred somewhere between the height at which he would normally have transitioned (200ft?) and the height he eventually reached (1000ft?).

To give this theory any validity, there would have to be some sort of anomaly warning (sound/vibration/warning system?) that would encourage the pilot to believe that continuing to gain height enough to attempt a safe autorotation was his best (or only) option. What might this have been?

[SASless]

At this point....without an official determination of what hellcopter flying skills experience, training, or knowledge the "Passenger Pilot" had at the time of the Accident....and without any information of "incapacitation" being an issue at all..... I would suggest we have not reached any level of being able to make an "assumption" and must limit the qualification of any such suggestion as being purely baseless pontification.

[Torquetalk]

At this point....without an official determination of what hellcopter flying skills experience, training, or knowledge the "Passenger Pilot" had at the time of the Accident....and without any information of "incapacitation" being an issue at all..... I would suggest we have not reached any level of being able to make an "assumption" and must limit the qualification of any such suggestion as being purely baseless pontification.

No, I don‘t agree with that. Earlier in this thread there was information offered by colleagues of the deceased as to the skill and knowledge level in the cockpit, from which reasonable conjecture can be made as to as to how the occupant of the other seat might have reacted in the event of incapacitation. But to be clear, my position was not that I thought incapacitation likely. I was disagreeing with that.

[gevans35]

It's my understanding that the passenger pilot had a fixed wing licence and not a rotary wing licence .if that is the case, and please correct me if I'm wrong, how would her fixed wing experience help her in a rotary wing environment?

If she had only worked the radios it would have been valuable assistance in high work load situations.

[rlsbutler]

If the case is that only the pilot is suddenly incapacitated, leading to an increasing yaw to the right, I suggest that an experienced fixed wing pilot in the other seat would know enough to stop the yaw.

If she knows the pilot has lost it, she would surely intervene with a bootful of rudder even if she did not know what else to do.

[helimutt]

So speculation as ever but given what has been observed so far it seems most likely that:
a) The aircraft was high enough at the apparent point of failure to avoid hitting the TR on any part of the stadium or other fixed object
b) Therefore the failure was likely caused either by something else airborne hitting it - or some sort of separate mechanical failure

Assuming the mechanical failure option, (in the absence of any clear evidence of another airborne object) one thing that still puzzles me is why the pilot chose to lift to such an apparently unnecessary height before attempting to transition into forward flight. Could it be that he was aware of some sort of anomaly on the lift out that made him want to gain extra altitude to have the option of an autorotation away from the confined space of the take-off site? If there was a problem near the ground he would presumably have just put it straight back down - so whatever it was presumably occurred somewhere between the height at which he would normally have transitioned (200ft?) and the height he eventually reached (1000ft?).

To give this theory any validity, there would have to be some sort of anomaly warning (sound/vibration/warning system?) that would encourage the pilot to believe that continuing to gain height enough to attempt a safe autorotation was his best (or only) option. What might this have been?

1000' ??? who said they got to 1000'? no way was it even half way to 1000' What you may like to focus on, which has been said here a number of times before, is that everything up until the point which appears to be his TDP, appears normal. It also appears that if he is following the correct AW169 departure technique (and we have no reason to believe otherwise as there is video evidence) then he will be yawed slightly left (if sat in the right hand seat) keeping the landing site in his view then just before transitioning to forward flight, will straighten the aircraft. (slightly movement in yaw to the right of probably up to 20 degrees or so)
It would also seem at this point that something departs the aircraft, but i'm not talking about the white speck seen at around 45 secs of the video doing the rounds, but the other white flat object which appears to depart the scene travelling up and left at approx 53-55 secs. (part of tail rotor blade?) I will try to provide a link to a youtube video showing this.

The media shyt regarding falling 'into a dead mans curve' (as if it is some mystical hell-like place that exists) is just laughable, and all of the so-called 'experts' that have been wheeled out and given their views, well, they've all either been seriously misquoted, or all talk absolute bollox to some extent. It's just as well that in the UK we have some of the best accident investigators in the world working on this. Some of the theories put forwards have been sensible and from the usual pro pilots on this forum, but the non-pilots who all suddenly become armchair experts do nothing but embarrass themselves when they put fingers to keyboards.

I think those of us who fly helicopters every day for a living, and have at least had some experience of tail rotor failures in simulators etc, will have a pretty good idea of some of the possible causes of this tragic accident, but unfortunately what we don't have access to are the facts except as shown in grainy videos.

So the media outlets will be trawling forums, and asking these crap-and-past-it experts for opinions based on poor real world knowledge, and a serious lack of facts. Again its a sad case of not letting the truth and fact get in the way of a good newspaper-selling story.

[helimutt]

My thoughts keep reluctantly focussing on sabotage. Swift removal of TRGB drain plug?
all billionaires cultivate serious enemies.



really? doesn't this even embarrass you writing something as stupid? so someone quickly ran out into the centre of a brightly lit football stadium, with some step ladders, probably had to remove a panel, drained the oil onto the field, then just walked away? honestly some folk need to go get a life. you've been watching far too much crap on tv.

[jeepys]

Helimutt, thank you. It had to be said.

I guess you got fed up with all the 1 in a million theories and daft perceptions out there.
It seems incapacitation is the new buzz word on the street. I don’t know what the statistics are but I am pretty sure this doesn’t happen very often.
Sabotage, haha.
300 hour aircraft-Very new type into service is exactly why the reason this is most likely a TR gearbox/drive fault. Remember it’s bigger older brother, the 139, and the early days of tail pylons falling off and blades letting go.

There are dreamers and realists in this world. I guess it makes fun to have both types around.

[Sky Sports]

Does anyone on here know how close the anti-coll wiring loom sits to the TRDS?

[noooby]

Yes, the gearboxes have "run dry" times. From memory the MGB is 53 minutes. I don't know about the IGB or TGB but they're under a lot less stress than the MGB.

As far as the "smoke/unburnt fuel" on engine start, it looks like steam to me. Had this quite a lot with 139 starts in cold weather with hot engines. Moisture would condense in the exhausts and give quite a good puff on engine start. Of course, the 169 doesn't have the monstrous exhausts of the 139!

I also note that the wind is up the tail on start.

Anyone know the critical wind quadrant/velocity for LTE????

Was the gear retracting on the climb? Unrelated but shouldn't it be after TDP when Vy is reached that the gear handle is moved? So hard to see details on the videos!

[tottigol]

What was TDP, anyone able to figure it out?
Anyone with CatA experience would know what I am talking about.

[Silver Pegasus]

Just something to bear in mind when criticising two of the better qualified TV speculators.. There is footage from at least two HD/UHD cameras that Sky for example may already have access to show them, even though it was BT Sport showing the match.. I do agree that it is initially insects on the CCTV but the other footage will confirm from there on. They may have also had CCTV submitted to them but not decided to publish it due to its nature (ie clearer and more shocking). The CCTV footage was only shown by the big stations due to the Sun doing so.. disgracefully. However it does allow us to rule things out so for us it isn't a bad thing.

[Jagwar]

It has been a few years since I flew heavy helicopters but fundamentally the loss of TR control 200-500 feet above the stadium was not survivable.

The AAIB will want to quickly establish the '4 corners' of the accident to confirm that all the components of the aircraft are present at the crash scene. One video shot seems to suggest that a component flew away from the aircraft with high energy immediately before control was lost, the only components posessing such energy would have been a MR pocket (or two) or a TR blade. The fact that the aircraft immediately lost yaw control indicates it may have been a TR blade.... Crash site pictures indicate 2 TR blades present but one is half missing, you could argue it had been consumed in the post crash fire but the edges appear jagged as if it had been torn apart rather than burnt. The AW 169 has an impeccable safety record with no history of TR blade mishaps or other TR drive or contol problems. So why in this case?

TR blades are stressed in construction so as to survive a minor impact from a birdstrike and still perform their role. In this day and age modern helicopters do not crash because birds fly through the tail rotors. In-service failure due to substandard manufacturing is a possibility but frankly unlikely. It is much more likely that a foreign object struck the tailrotor causing sufficient damage to cause blade failure and separation.... But caused by what? The surrounding area several hundred yards in every direction will be thoroughly searched for debris.... who knows what else might be found?

Might we be looking at the first fatal aviation accident due to an aircraft colliding with a drone?
The stadium is located next to the River Soar which has a fair quantity of resident Canada geese , they are are known to fly at night - would a TR survive a strike from a bird of this size?

[monkey_see]

What was TDP, anyone able to figure it out?
Anyone with CatA experience would know what I am talking about.

Variable TDP on the backup takeoff is up to 400ft.

[noooby]

What was TDP, anyone able to figure it out?
Anyone with CatA experience would know what I am talking about.

Max crosswind 10knots. No tail wind allowed.
TDP is up to 400ft in the Variable TDP profile. Depends on the height of the obstacle.

The calculation of TDP is: TDP=Height of Obstacle + Clearance Height from Obstacle + 80 ft. Using the graphs (poorly) and not knowing the ambient conditions/weights/exact height of obstacele etc, TDP could be around 330ft. That assumes the stadium to be around 200ft high.

If TDP calculates out to be 400ft or more then you are weight restricted.

Climb rate should be less than 300ft/min on the vertical climb. So from the video you should be able to (very roughly) estimate their height above the pitch when they looked to hit TDP and pole forward.

All approximate and not to be taken as gospel!!!

[Non-PC Plod]

To add something to the debate-
I tried TRDS failure at 300' TDP in the AW169FFS. daytime, & knowing it was going to happen. I survived.....but only at the second attempt! Main problem was having to look inboard to get the engine mode switches , which are located significantly out of your line of sight if looking out of the windshield (using left hand, which means removing it from collective!).
I honestly think the chance of getting away with it for real, single pilot at night are pretty close to zero.

[DOUBLE BOGEY]

Yes, the gearboxes have "run dry" times. From memory the MGB is 53 minutes. I don't know about the IGB or TGB but they're under a lot less stress than the MGB.

As far as the "smoke/unburnt fuel" on engine start, it looks like steam to me. Had this quite a lot with 139 starts in cold weather with hot engines. Moisture would condense in the exhausts and give quite a good puff on engine start. Of course, the 169 doesn't have the monstrous exhausts of the 139!

Anyone know the critical wind quadrant/velocity for LTE????!

STEAM 😩 I sort of promised myself to try to be a kinder person. For the love of god though! It’s unburnt atomised fuel. Not entirely normal but utterly harmless. You can take that as fact.

LTE - loss of tail rotor effectiveness. Jesus! .............

From the video......it looks very much like a sudden loss of TR thrust. That’s all that should be inferred. There are numerous possible reasons for that condition........none of which can be identified from the evidence in the video.

[malabo]

Careful using any FFS for analyzing technique on this kind of emergency. They are not programmed for it and generally don't have the flight data anyway, so you are working off a programmer's hunch. Years ago the CAE 412 and Flightsafety 412 sims had noticeable differences to tailrotor malfunctions, corrected only after a Canadian Forces 412 that was fully wired for HUMS/FDM suffered a for real tail rotor failure and provided accurate modelling information. Looks like this accident will do the same for the 169 sim.

For all you sim jockeys, have a feel at the yaw difference between knocking the engines off and bottoming the collective. I used to do it old school with the aircraft on 212/412 and there was a substantial difference between the two that was not captured on the sim models. Same with the nose down overpitching.

[DIBO]

watch the clip carefully ...at around 53-56 seconds.

nothing sensible to add, except that the 'unidentified object' disappears during 3 frames in between it's appearance on the port side and then on starboard
https://cimg8.ibsrv.net/gimg/pprune.org-vbulletin/607x637/aw169_uo_aa0d9ffff60346551394170485cf9fdba9f064ec.png

[Thomas coupling]

If anything - this thread has brought out some complete and utter moronic statements from so called pilots.
Goes to show either the helicopter industry is plagued with idiots or infiltrators from another planet!
Please think before you press "reply" FFS.

Christ - why should aviation tremble...................

[Ewan Whosearmy]

Well, the BBC's "experts" are plumbing new depths for their analysis:

https://www.bbc.co.uk/news/uk-england-leicestershire-46044224

Do these people, or the BBC, realise how stupid they sound?

"Mr Bray agreed: "It's normal because it's just starting up. When you start an engine up, sometimes you get some vapour or something coming out."

""He takes off, goes up and hovers above the stadium, because then he has got to assess which way the wind is coming and wind speed and everything else," said Mr Bray."

Mr Bray said a mechanical fault was also possible, but he believes this is unlikely.

"These things are checked to the nth degree and any professional pilot will want to make sure his aircraft is safe," he said.

"Obviously, they are putting their own lives at risk.

"It's very, very weird."


Of tail rotor failures, Mr Rowlands says:

""Thankfully, they are not the kind of things that happen often and I certainly don't have any personal first-hand experience of a real one, and I don't know anybody who does."

and

Mr Rowlands believes the pilot manoeuvred the aircraft to prevent loss of life to people on the ground.

"The fact that no-one else apart from people in the aircraft were injured is pretty amazing and I think that's why it's testament to the pilot," he said.

"It's quite a disorientating environment to be in and I think the pilot has done well because not only has he got control of the aircraft, but he's trying to minimise the impact of any incident."

I think I speak for many here when I say: Mr Rowlands, if you want to position yourself as an expert in looking out of the side of a helicopter (Puma crewman, no?), then great. But stop talking about flying unless you have some kind of rotary wing pilot rating. Mr Bray, perhaps you should do the same.

And, BBC, you might want to redefine what an expert is, because you appear to have found two who don't even approach the standards required to be labelled as such in an aviation context. The fact that I am in some small way paying for you to spew this crap makes me sick.

[helimutt]

nothing sensible to add, except that the 'unidentified object' disappears during 3 frames in between it's appearance on the port side and then on starboard
https://cimg8.ibsrv.net/gimg/pprune.org-vbulletin/607x637/aw169_uo_aa0d9ffff60346551394170485cf9fdba9f064ec.png
that’s not the item I was thinking of. Aircraft is turned much further right in the one I saw.

[Magplug]

The mention of 'dead man's curve' by the media is not so much rubbish as is being represented above.

It you suffer a TR failure in any conventional helicopter in a normal hover then you have no option but to check down on the collective and cushion the subsequent touchdown. If you are in a hover high above the ground then your chances of a tidy touchdown diminish with height. Away from the ground the only way to stop the spinning from the anti-torque reaction is to chop both engines by simultaneously retarding both power levers and dump the collective to enter autorotation.

Unfortunately you now have another problem of sorting out the self-induced double engine failure. You now need forward airspeed of at least 40-60 knots to execute an engines-off landing. To gain that airspeed you have to pitch sharply nose-down which not only increases your rate of descent but appreciably kills some of your remaining rotor RPM which is your life blood in executing a successful EOL. The chances of a succcessful EOL from a free-air hover of between 50 and 1000 feet are negligible.... even before you consider the complication of the confined area beneath you..... that's the dead man's curve.

[SASless]

TC......the good news is the Idiots among us usually thin their own Herd for us!:uhoh:

[gulliBell]

...Away from the ground the only way to stop the spinning from the anti-torque reaction is to chop both engines by simultaneously retarding both power levers and dump the collective to enter autorotation.
.

Other way around. Collective full down first, then sort out your recovery attitude and think about your plan. There is no hurry to get the engines off if you've backed off most of the power with collective and you have height to play with. If you have airspeed the tail fin will give sufficient anti-torque against the engines at low power, just accept out of trim flight. Engines off (not idle) before flare for auto-rotation landing. It is far more important to get the collective down and re-establish a stable attitude after TR drive failure than rushing to get the engines off immediately.

[Magplug]

@gullibell... Thank you for jumping in...... I was establishing the principle rather than trying to teach the technique!

@Jagwar... Good point about the Canada Geese. They are substantial birds and would one damage a TR? Who knows? They are however big birds that would probably show up on the video clip and they do tend to fly around in pretty formations, generally only flying by day. If there are significant bird remains on the ground, they will be found by the AAIB.

[player104]

So I’m just reading the various actions to take to maximise the probability of the theoretical best possible outcome, and I can’t help wondering why not use some or all left cyclic in addition to the forward cyclic to get the desired helpful airflow against the vertical stabiliser?

[Gustosomerset]

If you are in a hover high above the ground then your chances of a tidy touchdown diminish with height....The chances of a succcessful EOL from a free-air hover of between 50 and 1000 feet are negligible.... even before you consider the complication of the confined area beneath you..... that's the dead man's curve.

So, if some of the observations above are correct and the pilot chose to climb to an unusually high hover, why might he have done so?

[Torquetalk]

So, if some of the observations above are correct and the pilot chose to climb to an unusually high hover, why might he have done so?

High does not imply unusual. 50ft, 100ft, 1000ft could all be described as high hovers. There could be any number of reasons why the pilot might extend the climb beyond a minimum required to safely commit to the take-off, or none. No implication can be drawn as to it being either unusual or unsafe in this context.

[Gustosomerset]

OK, thanks. I understand. I guess I was just trying to see if any implication could be drawn from what some observers seemed to describe as an 'unusual' take-off. Evidently not.

[Ewan Whosearmy]

The mention of 'dead man's curve' by the media is not so much rubbish as is being represented above.

<snip>

The chances of a successful EOL from a free-air hover of between 50 and 1000 feet are negligible.... even before you consider the complication of the confined area beneath you..... that's the dead man's curve.

When I did my PPL(H) in 1998, an AFI demoed an auto from the hover at 1,000'. Rolled off the throttle, dumped collective, pedal turned through 180, controlled RRPM with lever, nosed down for forward airspeed, flared and cushioned landing with lever in the normal way. Type was R-22.

I was only shown it because I asked to see it, but when I asked what its real-world applicability was, they said it would most likely be a skill for pilots doing line work and pylon work. They seemed to suggest that if you took out the pedal turn, you could achieve the same from significantly lower than that.

[jeepys]

Gusto, despite what some ‘experts’ are saying that take off was quite normal.
Remember Ex is a has been and spurts is a little more than a drip!

[VintageEngineer]

I have some experience of crash investigations, helicopter engineering and statistics.

Let me shed some light in response to previous comments on the TR:
@ The pdf file below has a blown-up section of an image at the crash site (I can't yet post images directly). It clearly shows that:
@The TR was complete and attached at impact.
@ One blade was burnt by the fire after impact and appears to be broken in 2, with the outer portion lying on the boom just below the remaining portion..
@ One blade had damage to its tip.
@ IMO the lack of damage to the blades suggests the TR was turning very slowly or not at all on impact.
@ IMO the damage to the blade at the right bottom corner of the image almost certainly occured on impact with the ground.
@ IMO the damage to the burnt blade is consistent with the rotor not turning on impact and the blade fracturing, possibly helped to fall off by the post-crash fire.

On a final note, that a TR failure is a rare occurrence is essentially irrelevant to assessing whether it occured here or not. Even if it is a 100 million to one chance of occurring, it will occur to someone; we are not looking at the other 99,999,999 flights where it didn't occur.

[aox]

Removal from scene begins

https://www.bbc.com/news/uk-england-leicestershire-46069679

[Jagwar]

@gullibell... Thank you for jumping in...... I was establishing the principle rather than trying to teach the technique!

@Jagwar... Good point about the Canada Geese. They are substantial birds and would one damage a TR? Who knows? They are however big birds that would probably show up on the video clip and they do tend to fly around in pretty formations, generally only flying by day. If there are significant bird remains on the ground, they will be found by the AAIB.

Magplug: take a look at Google maps , the river forms a large basin only 50m from the stadium , I live near water and birds (ducks, geese) regularly land in the early evening even when dark , but not in formation I hasten to add !

[b1obthebuilder]

It's my understanding that the passenger pilot had a fixed wing licence and not a rotary wing licence .if that is the case, and please correct me if I'm wrong, how would her fixed wing experience help her in a rotary wing environment?

She would know what yaw is. Also know what the pedals do. And be an extra pair of eyes for the pilot.

[pilotmike]

I know that the weather at the time would appear to contradict the formation of a vortex ring, but could the explanation be as simple as that? High power vertical slightly reversed climb followed by a turn and drift into a vortex of descending air?
I naively believed vortex ring susceptibility was down to forward (or other direction) airspeed, rate of descent, and application of power. Remove any one of the three and the conditions cease to exist. I'll have to go back to basics to factor in weather.

For everyone's benefit, where can we find a comprehensive table of the weather factors, and precisely how they similarly cause - or 'contradict the formation of vortex ring', as you put it. I'm not convinced you know what vortex ring state is, given your phraseology.

[slfool]

Guys and girls that fly helicopters, or are learning to fly helicopters, will be able to discern the valuable posts from the obvious "b*****ks" or at least ask questions if they require clarification.

It's pretty clear which posts are "b*****ks" even to those of us who are mere SLF. I can understand how it must be immensely frustrating to the pros to see the drivel, but I don't think they should worry too much about it. From the descriptions on here and looking at the videos, it's clear to even the layman that if the helicopter is going round in circles the most likely reason is because something bad has happened at the back end. As for the exact cause, well the AAIB have a good track record by all accounts, and they now have the data recorder contents as well as the wreckage, photos and videos:

https://www.gov.uk/government/news/update-on-leicester-helicopter-accident-g-vskp
The digital flight recorder is in our laboratory. Although subject to intense heat in the post-accident fire, initial work on it has allowed us to successfully download the recordings. Our inspectors are verifying the extracted information and have started the detailed analysis of its contents.We would like to thank everyone who responded to our witness appeal. Our investigators are examining the videos and photographs we have received.

[Torquetalk]

When I did my PPL(H) in 1998, an AFI demoed an auto from the hover at 1,000'. Rolled off the throttle, dumped collective, pedal turned through 180, controlled RRPM with lever, nosed down for forward airspeed, flared and cushioned landing with lever in the normal way. Type was R-22.

I was only shown it because I asked to see it, but when I asked what its real-world applicability was, they said it would most likely be a skill for pilots doing line work and pylon work. They seemed to suggest that if you took out the pedal turn, you could achieve the same from significantly lower than that.

But that was a simulated engine failure: The only yaw reaction is the one induced by the planned actions of the AFI. This accident looks like a catastrophic anti-torque failure in a helicopter with a much higher mass. The response will always be behind the event and the attitude of the aircraft at the point of failure and immediately following failure is not known. I really don‘t think a comparison can be made.

As an aside, the R22 will also indulge maneuvers that an AW169 almost certainly wouldn‘t. Zero speed auto? Expect an extremely dangerous rate of descent once the aircraft has finished accelerating (this in itself would require hundreds of feet) - lethal at low altitudes; 180 pedal turn during such an auto would also likely cause huge structural stress. Can’t imagine test pilots having that high on their list of things to try.

[John4321]

From the CV & FDR the experts can recreate the flight using the pilot’s inputs and the aircraft’s controls actual positions.

They should reasonably quickly know if there was a failure of the TRDS, TRGB or TR controls.

If there was a mechanical failure they should be able to check the HUMS data to see if it could have been spotted before it failed. If it could, they can check other AW169 aircraft HUMS data for similar trend(s) (this is much quicker and cheaper than grounding all similar aircraft).

It is vitally important that all parties are open and honest in the interests of Flight Safety. I fear that some may be less inclined to be so. Time will tell.

[flyems]

She would know what yaw is. Also know what the peddles do. And be an extra pair of eyes for the pilot.

Extra eyes: No question,
Flight controls: Considering the pilot's professional background, I would be surprised if the fixed wing pilot onboard didn't have the skill to fly that aircraft under normal circumstances.

My interest would be whether a pilot with an experience and skills profile similar to her would be able to take on an aircraft at that height (that has already entered an unusual attitude) and recover from that successfully.

[flyems]

Unlikely that incapacitation could cause a reaction like that.SND

What would an aircraft response congruent with pilot incapacitation look like?

[henra]

It certainly looks like a mechanical failure, 99% certainty based on the videos. Yet no emergency AD? No grounding? No response at all.

In order to justify a grounding there would have to be an indication of a general design flaw. In order to identify this they have to analyse what broke and how. I guess they are simply not at that point, yet.
For issuing an AD you need to have an idea what exactly to look for. Also this requires the identification what gave first and how. See above.
It could also simply be a maintenance issue (for the sake of the mechanics who last serviced it i surely do hope not) or indeed a Goose hitting the TR. Re the question if a Goose can damage a TR: You can bet so. Geese are veeery substantial animals (up to 15lbs !). When people are worried about a tiny DJI wiping out a TR, think about what an object 7 times as heavy will do.

[henra]

What would an aircraft response congruent with pilot incapacitation look like?
How should anyone know?
That surely depends on what the last action/reaction before passing out was:
Could be stepping in one pedal.
Could be pulling/pushing/doing something else with the cyclic.
Could be pulling/pushing the collective.
Could be anything.
Could be nothing at all.

[Ewan Whosearmy]

But that was a simulated engine failure: <snip>. I really don‘t think a comparison can be made.


Understood. I was simply responding to the catch-all comment that no helicopter can survive an engine failure (he wasn't talking about TR failure) "from a free air hover between 50' and 1,000'".

[Oldlae]

The helicopter is at Farnborough.

[Torquetalk]

Understood. I was simply responding to the catch-all comment that no helicopter can survive an engine failure (he wasn't talking about TR failure) "from a free air hover between 50' and 1,000'".

The context was trying to auto to deal with a catastrophic anti-torque failure within that height range.

[Cabby]

Having watched the video's it looks like the a/c just dropped while spinning. If the pilot had become incapacitated I doubt the front seat passenger would have had time to do anything with the controls.

In the offshore industry pilots are trained incase a pilot ever becomes incapacitated. The technique used is to pull back on the collapsed pilots harness, which isn't as easy as it looks, while making sure the seat harness locks are on, to stop the pilot falling forward onto the controls.

In the video taken from the pitch it would appear that the a/c engines are still running during the descent as there doesn't appear to be any change in the noise, so the pilot didn't turn the engines off. The witness on the ground said it went silent? Maybe lack of tail rotor noise on the descent?

The lack of any AD's nearly a week since the accident to check other AW169's, makes me wonder if the AAIB haven't found any obvious mechanical failures at the moment? Does the AW169 type have a cockpit voice recorder?

What surprised me watching the video taken near to the crash site was the way the post crash fire seemed to consume the cabin Very quickly. The two brave pc's who approached the crashed a/c managed to get close to the cockpit until an explosion made them move away. Don't Leonardo fit crash proof fuel tanks to this new type of a/c?
When was it last serviced, and was the AD sent out to all operators in Sept 2018 for the Emergency Windows, actually completed?

https://www.bbc.co.uk/news/uk-england-leicestershire-46017499

[olster]

I knew Eric well and am deeply saddened by these events. As an airline pilot of some reasonable experience my aviation mid life crisis was to take a ppl (h) course. This took 7 years to complete part time probably a) because I was fairly useless and b) the eye watering expense. Hugely enjoyable, though and I finished in 2014.Ironically, Eric was one of my subject matter experts I phoned for all matters, rotary. The point that I will make that even with my experience as a professional fixed wing pilot, my initial embarrassingly ham- fisted attempts to control the R22, exponentially in the hover would in my view, make it unlikely that Isabella sitting in the other seat could really assist in a catastrophic event assuming she really had no official helicopter qualifications. Anyway, RIP to all.

[staplefordheli]

Magplug: take a look at Google maps , the river forms a large basin only 50m from the stadium , I live near water and birds (ducks, geese) regularly land in the early evening even when dark , but not in formation I hasten to add !

Or Mute swans, there are plenty on the river and they do overly the KP as i have seen many times at games myself even in the dark and they are even larger than a goose up to 33 ibs Hitting the TR disk square on with little fwd speed or drifting backwards is a much higher chance than in fwd flight already mention back at the start and being under high loading at that point probably more catastrophic failure

https://www.pprune.org/rotorheads/614822-helicopter-down-outside-leicester-city-football-club-not-condolences-10.html#post10295630

If it was a large illegally flown drone, then the police would already have been alerted due to debris found at scene on the Sunday night and be actively pursuing or arresting someone and it would be in the media IMHO
Any other failure due to component failure would have serious global implications and there is no grounding or inspections going on

[Davef68]

Assuming the mechanical failure option, (in the absence of any clear evidence of another airborne object) one thing that still puzzles me is why the pilot chose to lift to such an apparently unnecessary height before attempting to transition into forward flight.

I have no knowledge of the direction the pilot was heading in, but there are power lines on one side of the KP stadium which appear to be higher than the stands. The stadium is actually quite compact, and the stands aren't perhaps as tall as you might think (about 6 storeys from ground to roof, plus the cantilevers)

[Two's in]

Magplug, a very succinct description of a very possible scenario. The critical duties of a P2 following a loss of TR control is to to shut down the engines ASAP while the P1 attempts to enter Autorotation. As somebody else mentioned, with roof mounted ECLs, this is going to be difficult if not impossible for a single pilot. Whenever I flew with a non-rated person in the left seat, the duties always included a full brief on how to close the ECLs in an emergency, but thankfully I never got to find out if any of that information had been absorbed.


The mention of 'dead man's curve' by the media is not so much rubbish as is being represented above.

It you suffer a TR failure in any conventional helicopter in a normal hover then you have no option but to check down on the collective and cushion the subsequent touchdown. If you are in a hover high above the ground then your chances of a tidy touchdown diminish with height. Away from the ground the only way to stop the spinning from the anti-torque reaction is to chop both engines by simultaneously retarding both power levers and dump the collective to enter autorotation.

Unfortunately you now have another problem of sorting out the self-induced double engine failure. You now need forward airspeed of at least 40-60 knots to execute an engines-off landing. To gain that airspeed you have to pitch sharply nose-down which not only increases your rate of descent but appreciably kills some of your remaining rotor RPM which is your life blood in executing a successful EOL. The chances of a successful EOL from a free-air hover of between 50 and 1000 feet are negligible.... even before you consider the complication of the confined area beneath you..... that's the dead man's curve.

[Myra Leese]

This incident is surely the worst case scenario that any helicopter crew could experience. So far there has been very little advice offered on how you might survive such an event, presumably because few ever have. As an SAR pilot I have spent the majority of my career in high OGE hovers and TR failure was never far from mind. With that in mind I always took the opportunity during simulator currency trips to attempt to recover from a 300 feet OGE hover; the advice given which I tried to follow was- lower the collective, nose down for airspeed and roll into the turn then kill the engines if you could . The result was always a crash landing which was sometimes survivable. I know the sim is only as good as the engineer's model but for now it is the best we have but the one thing it cannot do is replicate the centrifugal force associated with the violent yaw experienced during a TR fail. Like Crab, I also knew and talked to the pilot involved in the Wessex incident and my stand out memory was him saying how hard it was to reach the speed select levers which were right next to the collective due to the spinning forces; more chilling was that I had delivered that airframe to Valley the week before and it could have been me.

Watching the video of this incident I would say that the pilot had cocked off to the left during the backup, as would be normal, and that the tail failure happens(if that is what happened) just as he kicks it straight prior to transition to forward flight. Is it possible that the two events are linked? I mention this because the Wessex incident happened during a tail rotor malfunction demo with an large pedal input used to simulate the malfunction.

[skadi]

Magplug, a very succinct description of a very possible scenario. The critical duties of a P2 following a loss of TR control is to to shut down the engines ASAP while the P1 attempts to enter Autorotation. As somebody else mentioned, with roof mounted ECLs, this is going to be difficult if not impossible for a single pilot. Whenever I flew with a non-rated person in the left seat, the duties always included a full brief on how to close the ECLs in an emergency, but thankfully I never got to find out if any of that information had been absorbed.

Does the 169 still have roof mounted ECL's? I think, like most dual FADEC ships, they just have Engine Main Switches on the centerconsole or instrument panel.

skadi

[Magplug]

@EwanWhoseArmy... The Dead mans Curve is establshed during test flying of a new type. A couple of test pilots start at say 2000' in the hover and chop the engine just as your instructor on the R22 did. They then enter autorotation and land. At the next attempt they bring the height down by 100' and repeat.... until they scare each other at which point they put an X on the graph and move on to the next part of the test. The Dead-Man's curve for the R22 will look very different to the profile for an AW169. Remember also... In a twin-engined helo the significance of the DMC is much less because you have two engines and the chances of one failing is very slim, the chances of two failing together in normal operation is infintisimal.

So, if some of the observations above are correct and the pilot chose to climb to an unusually high hover, why might he have done so?
The safest way to leave a confined area like a football stadium involves balancing risks in order to minimise you exposure to them....

- Climb vertically until you are clear of obstructions and in 'clean air'.
- For a twin-engined helo continue climbing until you have sufficient height clear of obstructions that you will clear them in transition if one engine fails and you lose some height.
- Transition to forward flight as soon as possible
- For a single engined helo do all of the above minimising your time inside the dead-mans curve.

FWIW I didn't see anything particularly unusual about the height he climbed to on the night of the accident.

@VintageEngineer... Whilst some of what you say about the TR debris is valid, you are drawing way too many conclusions from a simple photo. TR blades are of a complicated composite construction and the AAIB engineers will have to put it all under a microscope before pronouncing on the cause of failure.

[helimutt]

No roof mount ECL in 169 and the engine control switches are on centre console on right side, next to and aft, of the Emergency landing gear handle and normal landing gear handle.

[[email protected]]

As an aside, the R22 will also indulge maneuvers that an AW169 almost certainly wouldn‘t. Zero speed auto? Expect an extremely dangerous rate of descent once the aircraft has finished accelerating (this in itself would require hundreds of feet) - lethal at low altitudes; 180 pedal turn during such an auto would also likely cause huge structural stress. Can’t imagine test pilots having that high on their list of things to try. torquetalk - that manoeuvre was part of the standard post-maintenance flight test for a Sea King (much bigger than a 169) so there is no reason to expect that it hasn't been done on the 169 for certification purposes to demonstrate sufficient TR authority/control margin.

Myra - remember that it was the simulation of the TR/ASE malfunction that caused the TR disconnect coupling to disconnect - there isn't, to my knowledge, one of those on the 169 so an unlikely cause and probably the reason it didn't happen to you on the delivery flight:ok:

[flyems]

How should anyone know?
That surely depends on what the last action/reaction before passing out was:
Could be stepping in one pedal.
Could be pulling/pushing/doing something else with the cyclic.
Could be pulling/pushing the collective.
Could be anything.
Could be nothing at all.

Could be indeed, and I wholeheartedly agree with you.

It was the swiftness with which pilot incapacitation was dismissed based on the behaviour of the aircraft that made me wonder if it was an evidence based response.

[Myra Leese]

Crab,

That was my point, the Wessex incident occurred after the simulated malfunction caused the disconnect coupling to engage from its incorrect position and the subsequent torque shock loading snapped a TR drive shaft leading to the loss of TR drive. I know it was unlikely to happen to me but the underlying cause, compacted grease within the coupling, had built over time and would have been present during my delivery flight.

I know the 169 has no disconnect coupling but as I said, looking at the video it looks like the incident began just after the application of pedal to kick the aircraft straight prior to transition. Coincidence? Probably but until the data recorder has been analysed we only have speculation so I try to keep mine to observable occurrences, I wish others could do the same to discourage some of the nonsense contained in this discussion.

[Ewan Whosearmy]

The context was trying to auto to deal with a catastrophic anti-torque failure within that height range.

Got it. Thanks.

@EwanWhoseArmy... The Dead mans Curve is establshed during test flying of a new type. A couple of test pilots start at say 2000' in the hover and chop the engine just as your instructor on the R22 did. They then enter autorotation and land. At the next attempt they bring the height down by 100' and repeat.... until they scare each other at which point they put an X on the graph and move on to the next part of the test. The Dead-Man's curve for the R22 will look very different to the profile for an AW169. Remember also... In a twin-engined helo the significance of the DMC is much less because you have two engines and the chances of one failing is very slim, the chances of two failing together in normal operation is infintisimal.


Thanks, Magplug.

[FairWeatherFlyer]

The Sun's video shows the (red) strobe light clearly and it illuminates the disc in an interesting way. It flashes as regularly (a fraction over 1Hz) as you'd expect but something changes when the helicopter spins, even at the start of the spin it's not obvious anymore. I don't think strobe has stopped but something looks odd there. It could just be the yawing spreads the disc illumination making it far less visible?

[VintageEngineer]

@magplug. Thank you. You’re right. I agree that we should be careful being definitive, particularly based on one such image, which is why I included IMO. The AAIB will have access to far more than I do, although final assessments are normally unsurprising. I’m therefore happy for readers to take what I say with a pinch of salt.

Risking going off at a tangent, I had run my thoughts past a friend who works with composites for F1 and aircraft. He agreed with me, albeit based only on the image with all the restrictions you point out.

At least the image puts to bed a wild goose chase (hitting one would not cause that damage).:-)

[Torquetalk]

torquetalk - that manoeuvre was part of the standard post-maintenance flight test for a Sea King (much bigger than a 169) so there is no reason to expect that it hasn't been done on the 169 for certification purposes to demonstrate sufficient TR authority/control margin.

Thanks Crab. I had assumed that zero speed auto plus pedal turn would not be required for certification. Genuinely suprised it was part of a release to service flight: Some peole have all the fun.

[Viper 7]

In order to justify a grounding there would have to be an indication of a general design flaw. In order to identify this they have to analyse what broke and how. I guess they are simply not at that point, yet.
For issuing an AD you need to have an idea what exactly to look for. Also this requires the identification what gave first and how. See above.
It could also simply be a maintenance issue (for the sake of the mechanics who last serviced it i surely do hope not) or indeed a Goose hitting the TR. Re the question if a Goose can damage a TR: You can bet so. Geese are veeery substantial animals (up to 15lbs !). When people are worried about a tiny DJI wiping out a TR, think about what an object 7 times as heavy will do.

I've seen a sea gull descend into a turning sea king main rotor. The resulting feather explosion was impressive. A big goose and all those lights? Unlikely IMHO.

[Misformonkey]

Thanks Crab. I had assumed that zero speed auto plus pedal turn would not be required for certification. Genuinely suprised it was part of a release to service flight: Some peole have all the fun.
Zerospeed autos were done very frequently to confirm tail rotor rigging, did many as a FM.