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-   -   'RAF helicopter on fire' (https://www.pprune.org/rotorheads/582748-raf-helicopter-fire.html)

Bucaneer Bill 9th Aug 2016 13:44

'RAF helicopter on fire'
 
I saw this on the BBC News App and thought you should see it:

'RAF helicopter fire' on Snowdonia mountain peak

A fire, believed to involve an RAF helicopter, is burning at the top of a Snowdonia peak.
Disclaimer: The BBC is not responsible for the content of this email, and anything written in this email does not necessarily reflect the BBC's views or opinions. Please note that neither the email address nor name of the sender have been verified.


Sent from my iPhone

plexus 9th Aug 2016 13:46

[/url]https://twitter.com/huw_price/status/762993815636566016[/url]


https://pbs.twimg.com/media/Cpay03uXgAA5kvY.jpg

Bravo73 9th Aug 2016 13:47

A photo here:

'RAF helicopter fire' on Snowdonia mountain peak - BBC News

http://ichef.bbci.co.uk/news/624/cps...27_snowdon.jpg

Whether or not it is actually a photo of a burning helicopter is open to debate!

SATCOS WHIPPING BOY 9th Aug 2016 14:00

RAF helicopter crashes and catches fire in Snowdonia - BBC News

BBC now reporting that 4 persons on board are safe.

OnlyaPPL 9th Aug 2016 14:12

Being reported that it was a Griffen, had a tech problem.

Sky News

jimf671 9th Aug 2016 14:19

The Daily Post is reporting a Griffin down. Some sources state 4 POB and some 6 POB but all safe. 4 POB appears to be confirmed by MoD (below).

Indications that R936 may have already been on a job and R187 attended. Uncorroborated.


Daily Post also carries the following.

A Ministry of Defence spokesperson said:
“A Griffin training helicopter safely completed a precautionary landing in Snowdonia this afternoon following a technical issue. All four people on board exited safely, subsequently the aircraft caught fire. Emergency services are on the scene.”

Adam Nams 9th Aug 2016 15:01

Glad that all appear to be safe and well.
"Ok Bloggs, for practice..."

Fareastdriver 9th Aug 2016 15:18

Have an emergency and land on the TOP of a mountain. That's new.

SATCOS WHIPPING BOY 9th Aug 2016 15:34

Better than trying to land on the side of one.

jayteeto 9th Aug 2016 16:00

If it was a land immediately, maybe the bottom of the mountain was a LONG way away

Pablo332 9th Aug 2016 16:08

The MOD said five people - four military and one civilian - were on the helicopter at the time, while another person involved in the training exercise was already on the ground. (BBC)

Any reason MOD has deleted the 5th civilian?

[email protected] 9th Aug 2016 16:30

It might have been a mistake but there are a mixture of military and civilian instructors at SARTU (or whatever we are calling it this week).

If the emergency was an engine fire caption (which given the subsequent event doesn't seem too far fetched) then a 'land immediately', even on the top of the mountain, would be the right thing to do.

Very glad all are OK.:ok:

jimf671 9th Aug 2016 16:59

Are we not still calling it 202(R) Squadron 'this week'?

lowfat 9th Aug 2016 17:54

well all thats left is the tailboom... dust pan and brush for the rest of it....

212man 9th Aug 2016 19:08


Originally Posted by Fareastdriver (Post 9468234)
Have an emergency and land on the TOP of a mountain. That's new.

Probably better than bouncing down the side to the valley floor, having lost control as the fire takes hold!

Fareastdriver 9th Aug 2016 19:30

I see the reason; it's a Bell 412

dingo9 9th Aug 2016 19:56


Originally Posted by Fareastdriver (Post 9468481)
I see the reason; it's a Bell 412

DHFS have been operating 11 Grifins? Since 1996 in the training environment and I can only thing of one other incident ( single engine fail SARTU) I could be wrong.
That seems like a pretty good track record for the 412.

ShyTorque 9th Aug 2016 20:02

Did somebody leave the choke on?

Very glad to hear all POB safe.

oldbeefer 15th Jan 2017 10:38

Anyone from that well know training base in Shropshire have an update on what caused the problem?

Peter-RB 15th Jan 2017 11:42

They did well to get Fire services Up top of mountain,..or was that just some passing fire bobby with an extinguisher..

TorqueOfTheDevil 17th Jan 2017 08:26


Anyone from that well know training base in Shropshire have an update on what caused the problem?
Brexit, obviously

Beancountercymru 16th Aug 2018 21:12

The results of the enquiry have been published

https://www.gov.uk/government/public...nowdonia-wales

gulliBell 16th Aug 2018 23:50

Jeez, it would take ye ole' Air Marshal a month of Sundays to read that report. So in a nutshell, what happened? Was it something about the landing that caused the MGB mounts to crack and shunt forward? Or was it extremely fortuitous they cracked when they did in proximity to the ground during the course of normal operation?

SASless 17th Aug 2018 02:17

They could significantly shorten the Report.....by leaving blank....the pages "Intentionally Left Blank".

Saint Jack 17th Aug 2018 03:06

Yup, quite a tome isn't it! And it still bugs me that the people/persons who wrote it refer to that fine operator known as Bristow Helicopters as "Bristows", FFS it's "Bristow."

pitch horn 17th Aug 2018 11:31

Having read all 178 pages , for those who haven’t , the Main Rotor Gearbox Support Case cracked in 2 places.

gulliBell 17th Aug 2018 12:23

Yeah I know, but the main question is, did it crack because of something the crew did during the landing manoeuvre, or did it crack for other reasons and they were just lucky it cracked when it did and not whilst in flight?

Bing 17th Aug 2018 12:55

Gross simplification having read the report this morning.
The final cracking was probably caused by the manoeuvring to land on the mountain side. However the crack would have been propagating for some time, at least since the last visual inspection. The MRG SC is an un-lifed component so wasn't captured in the recovery programme when it was realised that MoD's interpretation of the aircraft limits was wildly different from Bell's* and a recovery plan had been initiated to get everything back to a safe condition (this was in ~2009).
So definitely some element of luck in that the manoeuvring to land caused the final over stress, but the crack would have been growing for some time.

*Bell basically said 'Aerobatic manoeuvres prohibited' which MoD turned into a 90 degree pitch and bank limit. Bell later revised the Flight Manual to read something like 45 deg of bank and +30 -15 pitch, which resulted in MoD having a bit of a panic attack.

JohnDixson 17th Aug 2018 16:26

On point, Bing.

The DSA team did a thorough job investigating this situation and their report reads clearly. It's not their job to implement corrective actions however, and the results of their work leave a challenging situation for the user, the regulatory authorities, and to some extent, perhaps the manufacturer.

Para 1.4.144/5 Maneuver Limits ought to raise the attention level of anyone involved in certification testing. Not pointing a finger at Bell. Users use, and stuff happens. I recall clearly the day when our CH-53A Project Pilot returned from a visit to the USMC MAWTS Squadron at Yuma, where they were teaching squadron pilots on how to use the maneuverability of the 53 to avoid enemy aircraft. He knew that our flight loads survey data didn't include what was going on there. Not close. Fixing that took some doing.

[email protected] 18th Aug 2018 09:17

It's a bit like selling someone a car that does 150mph and then complaining when they bring it back to you, broken, because they have been doing 150mph in it when you were expecting them to keep it to 70mph.

Revised Statements of Usage and Operational Intent have been the norm in UK mil aircraft - saw it in both the Lynx and the Sea King because the actual operational fatigue spectrum 'wasn't what it was designed for' and they needed more data. All despite being used within the limits of the ODM (RFM)

SASless 18th Aug 2018 11:28

How long had that particular part been installed....and had it been subject to the excess loading in the past...and not removed from service?

Remember how the discussion went about the Bell 407 that was "Looped" and found itself grounded as a result?

If I had an entire fleet of aircraft that had been flown in excess of the design and certification standards used by the manufacturer I would be having Kittens as well.....when confronted with a historical practice that far exceeded those standards.

Who is the guilty party....the Ute Builder who spec's the vehicle at one half ton load or the owner who runs around with two tons on it?

Whirling Wizardry 18th Aug 2018 11:42

I think I read that of all the global events of the MGB SC cracking, this same airframe had one in 2006 which was discovered on a post-maintenance ground run where the engrs found a leak.

The revised flight envelope had already been put in place at that time and the aircraft will have been operated within those limits. Prior to that time, the main flying exercise being taught that exceeded Bell's recommended pitch & roll flight envelope was wingovers which was removed from the Griffin syllabus as soon as the new operating limits were known.

JohnDixson 18th Aug 2018 12:02

Crab, SA, and Wiz make an excellent point: the fatigue spectrum is composed not simply of the specific maneuvers, but how many times they are accomplished, and at what weight. Best example I can think of on the weight side of things is what happened to the original S-64 Skycrane when it went into the logging business, compared to the original load spectrum within the military usage. ( and yes, that flight operation also changed the maneuver spectrum spread in that, for example, they would spend a lot more time coming down a mountain side on the edge of translational lift with high n/rev vibes ).

Bing 18th Aug 2018 12:33


Originally Posted by SASless (Post 10227197)
How long had that particular part been installed....and had it been subject to the excess loading in the past...and not removed from service?

My understanding from reading the report is that due to it's un-lifed nature the part wasn't tracked so no one can actually answer that question, or indeed where other ones from the RAF fleet may have got to. Bell considered the visual inspection interval would catch any cracks before they propagated to failure so it wasn't thought to be a problem.
There is a recommendation to find out where the parts have got to, which as pretty much any 412 serviced by Bristow could have received a MRG SC that had been used at DHFS seems like a good idea.

[email protected] 18th Aug 2018 13:34

But if Bell were really concerned, they could at least have insisted on removal and NDT of the SCs in question - rather than waiting for cracks to propagate - seems to me that they weren't that worried about wingovers causing the problem.

The sloping ground landings, on the other hand, are far more likely to have been a causal factor since the bending stresses on all the MRGB components are obvious and with student mishandling, likely to exceed design tolerances far more easily and far more often.

gulliBell 18th Aug 2018 16:14

All that aside, the choice of B412 in a training role - particularly for students straight off initial helicopter course - does seem a little odd to me.

JohnDixson 18th Aug 2018 18:29

My interpretation of the use of the term “ un-lifed “ means that the measured stress from the flight loads survey flight test was under the “ endurance “ level, i.e. possessed infinite fatigue life when flown in that set of conditions/maneuvers/weights. There are some implications here. Perhaps I’m wrong re that verbage?

If memory serves, when Harry Jensen and his group at SA first arrived at the methods/test requirements etc associated with establishing the Safe Life concept in the helicopter business, there was a group at Bell doing similar work. That being true, I’d assume they’d be quite interested and able in following up on this situation.

SASless 18th Aug 2018 21:32


My understanding from reading the report is that due to it's un-lifed nature the part wasn't tracked so no one can actually answer that question, or indeed where other ones from the RAF fleet may have got to.
Indeed!

Even with "Tracked" Parts it gets tedious over time to be able to start back tracking to the starting point.....rather than having the starting point at first fit when new and then follow the item as it is passed down.

When you conjure up the difficulty that entails when the tracking is an after thought.....no telling where those parts went to over the years.

[email protected] 19th Aug 2018 06:42


All that aside, the choice of B412 in a training role - particularly for students straight off initial helicopter course - does seem a little odd to me.
I think it was a question of what was available at the time - the aircraft needed to be a twin, with a big enough cabin for rearcrew training, the capability for winching, underslung loads, SAR etc and be robust enough for intensive military flying training - the 412 seemed to do a pretty good job for nigh on 20 years.

The DHFS single squirrel to 412 training regime replaced the RAFs Gazelle to Wessex training pipeline (which again had worked very well for many years) the new variant, MFTS with 135 all through and a smattering of 145 at the end, doesn't seem to be faring quite so well.

oldbeefer 19th Aug 2018 10:53

I was involved in the selection process for the twins for DHFS and we were limited to those types proposed by the various companies tendering for the task. In addition to the roles Crab mentioned, the requirement was also for navigator training in a centre seat. That precluded the BK 117 where the control runs were through a large 'box' from floor to roof between the pilot seats. The other types were MD 900, AS 365 and AB 109. The 412 was the winner by quite a clear margin, the others either lacking cabin room or had wheels considered too small for soft ground running landings. Was fun flying all those types for a week though!


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