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-   -   Martin Baker to be prosecuted over death of Flt Lt. Sean Cunningham (https://www.pprune.org/military-aviation/584971-martin-baker-prosecuted-over-death-flt-lt-sean-cunningham.html)

dartmoorman 26th Sep 2016 17:22

MOD and MAA full report here :-


overstress 26th Sep 2016 18:02

I am not sure when that modification was introduced. Was it pre 2013?
The Tornado seat was designed that way. It uses the Mk 10A seat, gas operated. I last flew one in 1994.

jumpseater 26th Sep 2016 18:20

I seem to recall there being an issue with some of the adjustment (Tourqe) setting of the shackle assembly. Data was passed to some customers, but not the RAF or RAFAT specifically. If my memory is correct then that might be the issue HSE are targetting, the failure to communicate correct procedures for use of their equipment.

hoss183 26th Sep 2016 18:26

In reading the report, i can imagine the prosecution relates to the finding d "The panel concluded that the ability to initiate ejection in a manner different to the design intent was a contributory factor in the accident"
So not new evidence, but perhaps an argument for a design flaw. Its also mentioned that more modern designs have an unsafe position indication.
If the main chute had deployed we would probably not even be talking about this, but very sadly when the holes in the cheese align, bad things happen.
My personal opinion is that without MB and their excellent products many more pilots would have died to date, and it's therefore sad to see this action.

Haraka 26th Sep 2016 19:05 d "The panel concluded that the ability to initiate ejection in a manner different to the design intent was a contributory factor in the accident"
The fatal accident suffered by Steve Beckley with his Harrier at Yeovilton in the early 70's comes to mind.
P.S. ,Looking at Engine's thread regarding the MAA findings;

The MAA found that the CAUSE of the accident was the inadvertent ejection due to displacement of the seat pan handle.
Beckley wasn't strapped in his seat IIRC, but may have trodden on the seat pan handle.

Engines 26th Sep 2016 19:08

May I try to offer some background and analysis here, particularly on the findings of the MAA report...As Tuc observes, something is going on here. The HSE intend to prosecute Martin Baker, not the MoD or the RAF. However, the MAA's report doesn't contain much that would obviously 'hang' MB. But as for the MoD and the RAF...here's my take.

Firstly a bit of data. MAA reports define their accident factors via the following categories, in descending order:

Cause - the event that led directly to the accident
Contributory - Factors that directly or indirectly made the accident more likely
Aggravating - Factors that made the outcome of the accident worse
Other - None of the above, but could cause, contribute or aggravate a FUTURE accident
Observations - factors not relevant to the accident but worthy of consideration to promote better working practices

So, trawling thought the report, here is my summary of what the MAA came up with. I've focussed on the technical aspects that might affect any MB liability. Caps used for clarity.

1. The MAA found that the CAUSE of the accident was the inadvertent ejection due to displacement of the seat pan handle. Various CONTRIBUTORY factors were identified around the SPH design and use in service, also strap positions.

2. The reason that the pilot died was the failure of his parachute to deploy, due to an overtightened drogue shackle. This risk was known to some in MB, but not, apparently, to the MoD. The MAA found that 'Poor communication between stakeholders and the lack of a robust system of tracking amendments..(which) restricted the flow of safety critical information' was an AGGRAVATING factor. They also found that the shackle dimensions, combined with extant MoD guidance on nut fitment led to an interference fit. Shackle dimensions were thus judged an AGGRAVATING factor.

3. The reason that the shackle had been overtightened was RTI/Hawk/059D, which required the shackle to be disassembled every 50 flying hours to allow an NDT examination of a potentially cracked seat beam. The report reveals that although MB recommended a 14 day visual inspection, and 1710 NAS confirmed that the seat would be safe with a cracked beam, 22Gp decided that operating as such would 'undermine aircrew confidence', and so an NDT inspection was introduced. However, the report reveals 'the absence of a clear audit trail, poor Hazard Log tracking and a paucity of decisional meeting records', so MAA could find no rationale for this decision. This was stated to be an OTHER FACTOR. However, the (quite astonishing) lack of any safety case for the seat, while mentioned, is not identified as any sort of factor. If you don't have a safety case, it's not possible to conduct a proper hazard analysis of any proposed servicing change - like an RTI that regularly takes the drogue shackle apart.

4. The report makes it clear that once the original problem (seat cracking) was found MB and the technical specialists worked hard to get a mitigation out there. But, quite amazingly, the report doesn't comment on why an RTI was being used when an STI (required when MB was involved) should have been issued.

5. Finally, the report shows that RAFAT (Reds') engineering standards were not up to the mark as far as seat maintenance was concerned. Signatory and supervisory malpractices were considered to an OTHER factor, while absence of compliant engineer training was a CONTRIBUTORY factor. (Bear in mind that to compress the shackle, the maintainer had to cut new threads on the shackle bolt - this is definitely NOT good practice).

My thoughts - and with the usual warning that I am entering 'opinion' territory. The first thing that astonished me was why anybody would imagine that taking a seat shackle apart, in the aircraft, every 50 flying hours, was a safe thing to do. In all my years around jets, any work on a seat, especially the operating mechanisms, required a seat lift and return of the seat to the seat shop. The second thing was the absolute horlicks that happened between the HSA, the AES PT and 22 Gp in the development of the RTI. Who, in the name of all that is holy, thought that 'aircrew confidence' justified taking the risks involved in dismantling the escape system? Where was the RTI file? Where was the hazard log entry management? Where were the records of decisions? WTF?

I honestly don't buy the MAA's analysis. Here's my stab:

1. If the shackle had worked, this would have (very probably) been an incident, with the pilot surviving. It became an accident because he died. He died because his parachute didn't deploy. It failed to do so because the drogue shackle had been disassembled and on reassembly overtightened to such a degree that it jammed. The jammed shackle was, in my view, the CAUSE. The inadvertent operation of the SPH was a CONTRIBUTORY factor. (But see below)
2. The only reason the shackle had been disassembled was the RTI. I see the failure to issue a satisfactory STI as the main CONTRIBUTORY factor.
3. Lack of a safety case and a proper system for developing the STI were AGGRAVATING factors.
4. The shackle was overtightened because the information available to the maintainer wasn't complete. And the maintainer wasn't properly trained to do this job. Those, in my view, are also AGGRAVATING factors.

So, where would this leave MB? The worst that they appear to be on the hook for is not getting a certain piece of technical information out to the MoD, which may have been an aggravating factor. Or more probably, the seat pan handle design. Again, the lack of a safety case, which would have highlighted the hazard and shown the mitigations, is a key factor. In my view, the MoD and the RAF are a good bit further up the chain of responsibility here. The Reds' maintainers didn't do a great job, but they were really put in a bad place by a series of failures higher up the chain. Including systemic failures in the airworthiness management systems in the MoD and the RAF.

OK, I'm done, and apologies for the long post. Any thoughts out there?

Best regards as ever to those keeping things safe,


Trash 'n' Navs 26th Sep 2016 19:26

Spot on Engines.

The MAA not finding fault with itself or those in the MOD - who'd have guessed that?!

superplum 26th Sep 2016 19:44

Engines has given an excellent summary of the tech bits. What has not been mentioned throughout, is the diminution of the AAES technical knowledge across the plumbers' trade. That is partly the result of a more centralised, and/or contractorised, maintenance programme Does RAF Scampton have a seat bay (?), I believe not and the opportunities to gain such knowledge are few nowadays. Also, IIRC, on older design seats, the shackle bolt was shouldered and could not be over-tightened as such.

Chugalug2 26th Sep 2016 19:48

I totally agree with your analysis, engines. Indeed I can't see how anyone can reasonably disagree with you, as everything that you say is verifiable. I also agree with both you and tuc that something is going on here. If MB are going to be dragged to court then they have little to gain by keeping quiet, as they might have otherwise. So is that why HSE have done a 180? Are we at last to see the UK Military Air Regulator forced to account for its actions, or lack of them? Or will the establishment close ranks and form squares yet again?

Tinribs 26th Sep 2016 20:46

Causes liability?
As a qualified H&Safety risk assessor with 15K hours, mostly jet I feel entitled to an opinion which members may of course accept or reject

It seems to me that MB were obliged to design a seat which performed as nearl as possible to spec. When informed of problems they should rectify them as soon as possible. This seems to cover the shackle situation. certainly in my day JP Victor Canberra etc we were taught to check the "floppiness" of the shackle.

Considering the pins we always placed them in a designated location and I cannot see why an audible warning could not have been installed such that some type specific action would activate it. Say opening the canopy without the pins removed from the flight block, obviously this would not have been infallible but no seat modification would have been needed and the process easily understood.
Perhaps the audible warning could have been repeated to a sounder outside the aircraft that the seat was unsafe enabling linees to co-operate

tucumseh 26th Sep 2016 21:03

If I may add one observation to Engines' excellent summary.

An RTI is only permitted if the Design Authorities (Martin Baker and BAeS) do not need to be involved in any way whatsoever. A 50 hourly maintenance regime on a safety critical escape system most definitely does not fall into this category.

Engines 26th Sep 2016 21:31


Thank you for, as ever, timely and accurate addition to my overlong post. The newer MAP-01 regs aren't quite as clear cut (I think) but the main thrust is clear - if the DA is involved, it's an SI or an STI.

What's much clearer is what is supposed to happen when putting together any TI. I quote from MAP-01, Chapter 10.5.1 Para 1.1:

Prior to issuing an SI(T) (which includes RTIs) the TAA in conjunction with the Release to Service Authority (RTSA) and Handling Squadron (HS) must assess its effects on the Air System Safety Case, RTS and handling and operation in accordance with RA 5405.

So, when the HSA issued the RTI, who certified that they had assessed its effects on the safety case for the seat? They must have done, to issue the RTI as per MAA regs. But there WAS NO safety case for the seat. This is a clear failure of the HSA's airworthiness management process. And where was the RTSA? Did they also not know that the seat didn't have a safety case? And where was the MAA? When they assessed the HSA and the seat PT, how come they didn't spot that there was NO safety case?

Come to that, how did the RTSA issue an RTS in the first place without a seat safety case? How did ACAS sign that one off?

Once you start digging, you don't stop until you find the truth.

Best regards to all those who care, and do their best.


Just This Once... 26th Sep 2016 22:03

Engines - nail on head. If you pull the thread of thought regarding the seat safety case (or absence of) a little harder you will find a whole lot of people talking about how robust it was at the Mike Harland inquest. Yet a little while later we all found out that no such document actually existed, nor was one hastily crafted after Mike's death. They even got the RAF Chief Engineer to say how good MB were at managing the seat airworthiness.

No safety system, no lesson learned and then another death.

dctyke 26th Sep 2016 22:10

Originally Posted by superplum (Post 9521413)
Engines has given an excellent summary of the tech bits. What has not been mentioned throughout, is the diminution of the AAES technical knowledge across the plumbers' trade. That is partly the result of a more centralised, and/or contractorised, maintenance programme Does RAF Scampton have a seat bay (?), I believe not and the opportunities to gain such knowledge are few nowadays. Also, IIRC, on older design seats, the shackle bolt was shouldered and could not be over-tightened as such.

As you rightly say all the seats I serviced up to mk9 had shouldered bolts, incredible they should choose not to use them. Also in the days of seat bay that bolt was never touched as the shackle was release by firing off the barastat unit. Something that could not be done 1st line, hence the work around.

Davef68 26th Sep 2016 22:22

Originally Posted by PDR1 (Post 9521188)
Can I just say that in *my* experience (for what it's worth) the HSE don't pursue anyone unless there is a clear issue and a definite public interest in doing so? I would suggest that (if anything) they don't act often enough.



I would concur. Too much of what is blamed on 'Elf and Safety' in the press is actually Insurance or risk aversion. The HSE do a damned fine job and they don't bring prosecutions very often.

I do wonder if evidence or findings in the inquest have led to this, although i didn't follow the case that closely.

Easy Street 26th Sep 2016 22:34


Purely out of interest, I note that you have adjusted your stance slightly since the same issues were discussed on the original inquest thread, with you now being aligned precisely to where Chug was in Feb 2014. However I agree entirely with Chug's (and your!) assessment that the drogue shackle overtightening was the cause of the accident, with the inadvertant ejection being a contributory factor, and that the semantics do matter. It will be interesting to see whether the SI's analysis stands up to the judicial scrutiny it might end up receiving in this case.

Some of the comments in this thread already hint toward a theoretical defence from MB along the lines of "yes, there was a flaw in the firing handle design, but it was a zero-zero seat and the death was caused by MOD failing to maintain the drogue shackle properly". However that defence would only get MB so far when you consider that the seat is supposed to be safe to sit on when the aircraft is inside a shelter or hangar; a design flaw which allows inadvertant ejection in those circumstances could not possibly be mitigated by deflecting blame further down the ejection sequence. So it will be very interesting to see whether the charge relates to the seat pan firing handle design or the drogue shackle bolt tightening procedure: if the former, MB may well be in trouble.

It's a very different story if the charge centres on the drogue shackle bolt. I can remember being advised at some point during training on Mk10-equipped aircraft (either at Valley or on the Tornado OCU) to check the drogue shackle for freedom of movement during the pre-flight check of the ejection seat. I can't recall this being written down in any of the APs and my memory is of it being just another piece of received aircrew wisdom. However if anyone has kept a set of Hawk or Tornado FCCs from that era it would be very interesting to see whether 'free to rotate' or words to that effect are mentioned in connection with the shackle. I also remember direction being issued in the mid-2000s, as we entered a brave new world of safety, that ejection seat components should not be touched during the pre-flight checks unless specified in procedures. How ironic that this more 'modern' attitude might have removed a defence against error elsewhere. But I digress... the fact that such aircrew wisdom existed in the period between 1995 and 2005 (dates deliberately widened to preserve anonymity!) shows that someone, somewhere in MOD must have been aware of the potential for overtightening of the drogue shackle bolt. If MB's trial hinges on this point we could be in for a very interesting time.

To end: I hope that Theresa May's Government, with its professed interest in preserving British industry, prevails upon MOD to approach this case with a view to minimising the harm to MB's reputation. MOD isn't going to lose any of its "business" by owning up to faults, but if it chooses to obfuscate it would risk causing severe collateral damage to a great British firm.

Engines 26th Sep 2016 23:08


Thanks for coming back and contributing to a very good thread. I'd like to respond to your point about my 'adjustment of stance'.

i've consistently tended towards a view that the MoD's failures with regards to airworthiness (which are systemic and serious) were, and remain are, driven more by incompetence and ignorance rather than 'malevolence'. I did not and do not believe that anyone seriously set out to deliberately cause deaths and loss of aircraft. However, I do believe that decisions made by senior officers (and senior civil servants) to advance their own careers ('look how many millions of pounds I've saved by transformational change to my PT!') have led directly to those deaths. They continue to happen, and almost certainly contributed to Sean's death.

Where I do support the use of the term 'malevolent' is the ongoing effort to cover the whole issue up. Reputations are blackened, facts are suppressed and lies are told. In my view, that's probably going to be the thing that gets them in the end. Cover-ups usually do.

Incidentally, I clearly remember being briefed on seat pan handle safety on the Mk10 seat in the 90s, with a clear instruction to check that it was fully home before inserting the seat safety pin, and making sure it stayed that way after pin withdrawal. That was risk mitigation happening at the local level.

But here's the REAL point. If the seat HAD had a safety case, the issue of the seat pan handle would have undoubtedly been noted and recorded in the Hazard Log. That hazard would then have been 'sentenced' - that is, investigated, analysed and mitigated, against the extant Safety Case and build standard, with full input from the Design authority. Except, as Tuc would gently point out, the main mechanism for doing this activity (PDS contracts) was effectively cancelled from around 93 onwards. And, as late as 2011, the seat didn't even have a Safety Case, so none of this activity could have taken place anyway.

Hopefully, this one will run and run. Best Regards as ever to those keeping our aircrew safe right now.


Trash 'n' Navs 26th Sep 2016 23:10

the seat is supposed to be safe to sit on when the aircraft is inside a shelter or hangar
It's designed that way so "inadvertent" activation is either down to the design, maintenance or operation of the seat.

It seems odd that HSE have only focused on the designer when maintenance & lack of a safety case clearly contributed - if not caused this.

Tango837 27th Sep 2016 02:01

Jumpseater is correct, at the inquest it was stated that MB notified all users of the seat that there was a notice about the torque loading of the shackle except
the RAF and RAFAT were unfortunately omitted from the message. MB were
notified of the problem of shackle bolts in June 1992 .

AtomKraft 27th Sep 2016 10:34

Reading the report, I can see that his seat malfunctioned, as discussed in the thread- but not why it fired.

It seems to me that after completing his 'full and free' check, he brought the stick back sharply and his seat fired about 3/4 of a second later.

Why did it do that?

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