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Martin Baker to be prosecuted over death of Flt Lt. Sean Cunningham

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Martin Baker to be prosecuted over death of Flt Lt. Sean Cunningham

Old 17th Mar 2018, 10:49
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The fact it wasn't required to (!)
Tuc, I had to rack my brains but I reckon you're right. I'd like to hear MOD's response.
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Old 18th Mar 2018, 10:54
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RLE:-
So if MOD is culpable, why has the HSE not issued a Crown censure (as they did for the SAS deaths in the Brecon Beacons)?
A very good question. And why was MBA charged with an offence for not notifying MOD of the dangers of overtightening of the shackle bolt if they were no longer obliged to? Why did they plead guilty instead of producing evidence of their innocence and of MOD culpability? So many questions...
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Old 19th Mar 2018, 11:19
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According to the 2002 QinetiQ report the 'scissors' shackle mechanism was replaced on the Tornado seat with a GS drogue bridle release system because of a failure of the MBA trial in mid October 1998. The judge failed to mention this fact in her summing up. In fact she gave that impression that MoD had the gas shackle mod fitted out of the kindness of their heart, by stating, "This design is now an “old” design. Since about 1984 MBAL has not designed any new seats with a mechanical scissor shackle. Rather it uses an improved gas-release shackle system, available for new aircraft and also for retro-fitting. The MoD contracted MBAL to carry out such retro-fitting on all inservice ejection seats, with the exception of the seats in the Hawk aircraft." The judge also failed to establish why the Hawk seats were not modified.

Had the judge gone down the "why did MoD have the gas shackle fitted to the Tornado seat?" route, the QinetiQ report would have been revealed and with it MoD knowledge that the 'scissor' shackle could jam. In my opinion the judge turned a blind eye to the report, and in doing so failed the Cunningham family and the general public.

DV
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Old 19th Mar 2018, 11:48
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Or, as said earlier, the gas shackle modification was not introduced into MoD service as a result of a manufacturer identified hazard with the original shackle. Equally I am not aware that MB proposed the gas shackle modification to any foreign user to resolve a safety issue with the original design. I do not think a civilian AD was raised for the civilian operators of ejection seats fitted with a scissor shackle either.

Returning to the original flawed design, it can be resolved (and was) by a simple and cheap bolt change. There has been no panic upgrade to gas shackles as a result of this issue; the problem was a single-point safety critical failure in the original shackle and bolt design. If MB had gripped the issue when identified 2 or 3 decades ago the old bolt design would have been withdrawn and all seat users would have received a modified retaining bolt. As we learned, MB was still providing this flawed part to multiple customers up to and shortly after this terrible incident.

Of course, we should not forget the safety pin that, when inserted, may not actually make the seat safe, or the firing handles effectively becoming a hair trigger, or the man sep handles being fatally ‘live’ when the seat is still in the aircraft, or a seat design change leading to a seat coming adrift and killing its occupant, or QRFs that can inadvertently release the occupant post-ejection and I could go on... Not all was well in MB’s safety process and things had to change.
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Old 19th Mar 2018, 15:22
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JTO

As the 'quality of design' allegation was dropped, the only charge related to M-B not providing a technical bulletin in February 1990. Most of the issues you mention did not form part of the case. The media conveniently ignored this, citing the now discredited comment by the Coroner that the seat firing handle design was 'entirely useless' (and then disingenuously applying it to the whole seat).

The HSE deemed it irrelevant that M-B had provided the information both before and after 1990. What is the significance of the 1990 date? (I don't know). Perhaps the HSE did a trawl through records and said 'Ah, you didn't send it in Feb 1990'. But I don't see a raft of other customers who didn't get it then, including the US, taking issue. Perhaps because, like MoD, they already had the information, but had actually kept a copy and placed it on the internet for anyone to see. I didn't see the HSE quoting this information, which if followed would mitigate the risk of pinching the shackles (unless someone ignored both the instruction and their training and over-tightened the nut).

Poor training, and ignoring what training was given, has led to many more accidents than this. What makes this one different? Could it be that the high profile user makes it a good story for the HSE? Telling the judge that first hand witness evidence that the information had been provided was 'irrelevant'? I know who I'd have in the dock.
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Old 20th Mar 2018, 10:59
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Parachute Safety Assessment

In a 2015 Air Commodities 'Safety Assessment Report For Emergency Escape Parachutes', which cover types GQ1000 and GQ5000 it states that, "All parachutes have a 500ft minimum operating altitude". If that is the case how is it possible to use these 'chutes with zero/zero MB seats, when the maximum altitude achievable from a ground level ejection is only around 300ft, with rocket assistance?

DV
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Old 20th Mar 2018, 11:30
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DV. Parachutes

Good question, well presented, deserves an answer.

Perhaps it refers to other installations (static seats etc)?

Of course Ejection seat installations will have been subjected to comprehensive qualification test programs to prove (or not) whatever the system in a particular installation is. The parachute DA will undoubtedly have bought in to those tests, and I should think they had their own set of parachute installation QTP.

Perhaps PPruner "dragartist" or someone from Survitec (Maufacturers of GQRange) may wish to comment?
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Old 20th Mar 2018, 12:30
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Originally Posted by Distant Voice
In a 2015 Air Commodities 'Safety Assessment Report For Emergency Escape Parachutes', which cover types GQ1000 and GQ5000 it states that, "All parachutes have a 500ft minimum operating altitude". If that is the case how is it possible to use these 'chutes with zero/zero MB seats, when the maximum altitude achievable from a ground level ejection is only around 300ft, with rocket assistance?

DV
Possibly that's a condition for the parachute in isolation? AES parachutes are augmented by drogue deployment and/or aircraft speed.

EAP
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Old 20th Mar 2018, 12:35
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DV

The 500 foot minimum operation altitude must have associated with it a horizontal and vertical speed. Perhaps the 500 ft is based on zero speed in both directions, in which case it is the acceleration of the man and seat downwards under gravity that generates the energy required to inflate the parachute.

In the case of a zero zero ejection, while the seat is moving upwards under the force from the rocket motor, the drogue gun fires and when the drogue chute deploys it rotates the seat around so that the crewman is moving upwards, feet first. When the scissor shackle releases from the seat and the main chute deploys, the occupant and seat are still moving upwards. In this case it is effectively the inertia or kinetic energy of the seat moving upwards that provides the energy to inflate the chute, which is partially if not fully inflated when the occupant reaches his/her apogee at around 200 -300 ft depending on weight.

I cant remember all the timing details. However if you want more information, there is an excellent little book called Engineering for Life by John Jewell that I acquired many years ago courtesy of Martin Baker and I 'borrowed' one of our office copies just before I retired. It might have been updated since ours was published in 1979.

Walbut
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Old 20th Mar 2018, 12:50
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Originally Posted by Distant Voice
In a 2015 Air Commodities 'Safety Assessment Report For Emergency Escape Parachutes', which cover types GQ1000 and GQ5000 it states that, "All parachutes have a 500ft minimum operating altitude". If that is the case how is it possible to use these 'chutes with zero/zero MB seats, when the maximum altitude achievable from a ground level ejection is only around 300ft, with rocket assistance?

DV
Are you sure that's not just referring to conventional parachutes? Surely ejection parachutes have separate certifications.
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Old 20th Mar 2018, 14:17
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Originally Posted by walbut
DV

The 500 foot minimum operation altitude must have associated with it a horizontal and vertical speed. Perhaps the 500 ft is based on zero speed in both directions, in which case it is the acceleration of the man and seat downwards under gravity that generates the energy required to inflate the parachute.

In the case of a zero zero ejection, while the seat is moving upwards under the force from the rocket motor, the drogue gun fires and when the drogue chute deploys it rotates the seat around so that the crewman is moving upwards, feet first. When the scissor shackle releases from the seat and the main chute deploys, the occupant and seat are still moving upwards. In this case it is effectively the inertia or kinetic energy of the seat moving upwards that provides the energy to inflate the chute, which is partially if not fully inflated when the occupant reaches his/her apogee at around 200 -300 ft depending on weight.

I cant remember all the timing details. However if you want more information, there is an excellent little book called Engineering for Life by John Jewell that I acquired many years ago courtesy of Martin Baker and I 'borrowed' one of our office copies just before I retired. It might have been updated since ours was published in 1979.

Walbut
Indeed. (See my earlier) comprehensive QTPs for both equipment and installations will have been done.
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Old 20th Mar 2018, 16:28
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Indeed. (See my earlier) comprehensive QTPs for both equipment and installations will have been done.
Only one high speed sled test was carried out by MB for the GQ 5000 Tornado upgrade. There were no independent witnesses. Some time after the test QinetiQ reported in 2002 that, "The results recorded for the rear seat occupant ejection event (98-percentile) were successful, showing full parachute canopy inflation at 2.82s at a height of 36 feet above ground level". A tree level deployment seems a bit tight for me, with no consideration given for any sink rate.

The 2015 Air Commodities report does make it clear that, "ACT is not in a position to underwrite the safety of the items on aircraft; this is the responsibility of the Platform PT and RTSA. The Platform PTs and RTSA must accept any hazards associated with the continued use of these systems, with the risks endorsed by the Duty Holder." Would like to see that endorsement. Prior to the introduction of Safety Assessment Reports (SARs) in 2015 recommendations were articulated in individual AECs/SCRs, however no AEC/SCR was prepared for the GQ5000. Furthermore, there is no Certificate of Design for GQ5000 and GQ1000.

The Air Commodities report also points out that "The parachutes covered by this Safety Assessment Report are manufactured and supplied by Airborne Systems Ltd; either directly or via Martin-Baker Aircraft Ltd for seat-mounted parachutes, both being recognised internationally in the design, development and manufacture of parachute and aircraft escape systems. Airborne Systems Ltd is currently MOD Design Approved Organisation Scheme (DAOS) (ref: ALTG/07/03/11/291) approved for the equipment covered within this Safety Assessment Report, as is Martin-Baker Aircraft Company Ltd (ref: UK.MAA.DAOS.154), providing confidence that the company's' Quality, Safety and configuration management systems employed should be robust and effective."

It does appear that Airborne Systems and Martin Baker were allowed to carry out their work, unsupervised because of their 'good name' and reputation. Perhaps it is significant that on 22nd July 2014, after Tornado and Hawk accidents, the MoD drew up a tender document for the “delivery of Safety Assessment Reports (SARs) to detail the safety arguments and supporting evidence for the Aircrew Escape and Survival (AES) equipment covering: risks to wearer, hazards to relevant air platforms and fitness for purpose”. The reason for doing this was that “Aircrew Escape and Survival Safety Documentation does not satisfy current requirements, exposing Duty Holders legally and potentially Users to unknown or unquantified risks.”

DV
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Old 20th Mar 2018, 17:17
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DV

'good name' and reputation have nothing to do with it. The wording of Def Stan 05-123 used to say something like "the certifications of DAOS approved firms is accepted by MOD". MOD have the right to attend any test they want to and its usually a requirement of the contract that they are given notification in advance of such events.

The effects of sink rate, bank angle, pitch angle etc. are all worked out by calculation afterwards. There is no effective way of testing all combinations at reasonable cost.

EAP
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Old 20th Mar 2018, 18:02
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I think Walbut provides a good answer. One minor point of order. the use of the term Altitude vs height. Air Density and Temperature (the mass of air) affect the fill rate. not only the air entering the canopy but the air being pushed out of the way to do so. this is where the aeroconical wins. I still have my Hendrich course notes from St Luis University and some old spreadsheets used to calculate such stuff. Perhaps the rate of descent as the subject approaches the ground may be sufficient in all probability to make the impact survivable.
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Old 28th Mar 2018, 11:54
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As an aside....

Soz posted an incorrect link earlier,

Someone mentioned Chalgrove housing developments earlier in this thread.

There was a council meeting last night...interesting outcome.

Rethink needed after council rejects Chalgrove Airfield plan | Oxford Mail

Last edited by oldmansquipper; 28th Mar 2018 at 12:05.
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Old 28th Mar 2018, 13:23
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Thanks OMS, as you say interesting, or perhaps just irritating while we go through the long drawn out saga of MBA staying in situ and any chance of development there being quietly killed off? This orchestrated charade no doubt worked well enough in the days of paper and ink, but in these digital days of everyone knowing what everybody knows it simply places the various players in uniform and complete contempt. As for MBA, cheap at half the price?
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Old 1st Apr 2018, 20:04
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Originally Posted by walbut
DV


In the case of a zero zero ejection, while the seat is moving upwards under the force from the rocket motor, the drogue gun fires and when the drogue chute deploys it rotates the seat around so that the crewman is moving upwards, feet first. When the scissor shackle releases from the seat and the main chute deploys, the occupant and seat are still moving upwards. In this case it is effectively the inertia or kinetic energy of the seat moving upwards that provides the energy to inflate the chute, which is partially if not fully inflated when the occupant reaches his/her apogee at around 200 -300 ft depending on weight.


Walbut
I can confirm this from experience. The most surreal part of my Martin-Baker ride (0 ft / about 65 kts) was looking up (in my frame of reference) to watch RAF Valley receding rapidly in the overhead, then looking down to see my boots pointing at the sky.
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Old 20th Apr 2018, 10:16
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This case drags on. The Health and Safety Executive's legal department have found it necessary to forward exculpatory evidence to Martin-Baker's solicitors, proving MoD knew of the risks from Day 1 (introduction of Scissor/Drogue Shackle release mechanism). This was denied in court, and the HSE's charge was based on MoD's claim NEVER to have known the Drogue Nut should not be over-tightened.

Also, and despite reminders after the accident NOT to torque load the nut (also reflected by the CAA in Emergency Mandatory Permit Directives), the MoD chose to ignore this and still insists on it being torqued to 50 lbf in.

If MoD is permitted to ignore such directives, and destroy its corporate knowledge, at what point does providing warnings or advice to MoD become utterly futile? It was HSE's case that, had Martin-Baker provided (reiterated) a warning in February 1990, then MoD would have heeded it and Sean Cunningham's parachute would have opened. At any time, but especially given this fresh evidence, that is one hell of a jump.
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Old 20th Apr 2018, 13:18
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Does this new evidence mean that there might be a re-trial?
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Old 20th Apr 2018, 14:15
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Does this new evidence mean that there might be a re-trial?
It will be interesting to see if anything transpires. It certainly represents a shift in attitude from the HSE. If this latest evidence had been presented in court, who knows what the judge would have done, regardless of plea. But it does make HSE's claim to have conducted a 'thorough investigation' look risible. The significant point now is that, having dismissed previous evidence of innocence as 'irrelevant', the 'new' evidence is deemed relevant enough to warrant notifying the defence, and witnesses, that this action has been taken. I guess much depends on whether Martin-Baker want to do anything.
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