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Old 9th Jul 2007, 18:36
  #841 (permalink)  
 
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Safety Helmut
I have read the BoI for XV666 - as an aside, I took the photo that was on the cover of the report - the starter motor inadvertantly engaged and wound up outside it's design limits, shearing off the retaining nut which then ripped through the engine compartment into the fuel tanks, causing the fire
There had been many reports over the years of starter motor lights "flickering on" during flight, hence the modification - why 666 was not modified during it's major is a mystery - it should have been picked up on its pre-major survey
Tappers Dad
I am no longer a Captain, and in my last post, I intended the brief to be a hypothetical situation which would illustrate to this audience the ramifications of a Captain making such a brief - ie - he would no longer be a Captain despite having the balls to protect his crew
However, the answer you seek is in that brief, because in the event of a Bomb Bay fire, you are in the pooh, unless of course you are in the circuit, as was XV257, and you could get round and down in 2mins 57secs and walk away
SAR kit and torpedoes on fire can be jettisoned - a fuel fire, 'possibly' could be blown out by opening the doors, but that has to be balanced against feeding the fire with a rush of air - much like a blacksmiths furnace
Unfortunately, in the Release to Service, it's not possible to conduct Bomb Bay fire trials for obvious reasons, so design features and procedures are incorporated to negate that risk
However, as mentioned on this and other threads, technology exists where a space the size of the Nimrod Bomb Bay could be overwhelmed with an inert gas (Halon) to douse a fire but that would involve weight, size and expense
Every ac component has a 'life' with a built-in safety factor and is checked according to DA standards for the environment in which it's designed to operate - ie - a grommet, gusset, seal etc may be lifed for 2000 hours and is to be replaced at 1200 - ok in a temperate climate - but sustained exposure to 39 degrees+ for months on end may cause them to perish before their shelf life is up - these components are time related and may be hidden from view, so are not included in an AF/BF schedule, although they may have failed
In my humble opinion, Murphy's Law and Sod's Law creeps into this tragic XV230 incident - I have no doubts that Al Squires was happy to accept a perfectly serviceable ac for that sortie, complete it, and bring his crew safely home - and now we all have the benefit of hindsight - wow!!
I'll tell you all something - if it had been me looking down that Bomb Bay periscope, I would have been extremely worried, and even now, long after the event, I'm still not sure how I would have briefed the crew to instill confidence, knowing they were in serious trouble
Re-covening the BoI has Alistair Campbell plastered all over it
And oh! how I despise that man
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Old 9th Jul 2007, 19:22
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Yours is the first time that I have seen a comment that the FI installation was extensively re-engineered - not that this would necessarily meet all of the relevant standards, and carrying out a safety analysis is little use if its results were not to be implemented - were they?
I'm only going by what others who appear to have the credentials to know have reported - I have no direct knowledge of Nimrod AAR. I do not think they are making it up as their testimony, to me, is entirely convincing for a number of reasons that make it clear they are who they claim to be.

As I've said earlier, adherence to standards is no guarantee of safety, and it should be remembered that safety analysis typically occurs in parallel to design activities, in such a way that safety drivers and features will be an integral part of the design. Failure modes would be considered during the design and mitigated. My experience is that our industry are responsible and diligent in this respect. Safety analysis in this correct sense therefore is not a 'bolt on' activity afterwards when expensive to change design decisions have been taken. Furthermore this does not preclude 3rd party assessment either, both in terms of an Independant Safety Assessor (ISA - or its 1970/80/90s 'equivalent') being involved during design reviews, and also of course having your boscombe down types reviewing design reviews as well. I have no direct knowledge but feel fairly safe to assume this kind of safety analysis would have occured during any AAR re-engineering.

All of this aside having seen how the Chinook BOI was "manipulated" (which I will happily justify in a PM if you wish) I am, like everyone else, very suspicious of the reasons for the continuing delays!
Would like to hear more of your views on this, though to be honest my views on Mull/Chinook are, and I'm afraid some may not like this, is a 99.99% probability that the crew flew a Chinook that was operating normally to all intents and purposes into the Mull. There is much debate on the remote technicality that it could be something else, but when you look at the big picture it is extremely unlikely. I must stress that this is not to say that I agree with the negligence verdict for a number of reasons, but this is a different issue to the airworthiness of the aircraft in question and the bearing this had on the crash (i.e. to all intents and purposes from the balance of evidence available, absolutely none).
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Old 9th Jul 2007, 19:40
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JB & Tuc

Thank you both for the replies: I was curious as to what formalised engineering decision processes (eg risk assessments) might follow post-accident before allowing an aircraft to fly again.

I had to ask some questions here as my family are not happy about my work now and people at work might take the mick!

I think that I will wait for the BOI now.
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Old 9th Jul 2007, 22:24
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Bouy15
The aircraft we are discussing was XW666, you talk with seeming authority, unfortunately, you’re wrong in the detail, and more importantly, wrong in your conclusions.

First the detail. Yes there had been a history over the years of ‘flickering’ lights, but these I believe were Air Start Valve (ASV) indications. It was a short on the engine wiring loom of XW666 which caused an Air Start Valve to open, this was indicated on the flight deck by a warning light. This allowed air to go to the starter motor which ran up under no load. Before it’s design maximum rpm, a retaining nut failed. Now this is the real detail. The retaining nut failed because of hydrogen embrittlement, this failure mode had been identified about 10 to 15 years before, on at least two occasions. A modification programme had been instigated to ensure that all starter motor retaining nuts were replaced. This was nothing to do with flickering ASV lights, it was because starter motors could fail before their design maximum rpm. If they failed, as XW666 showed, the effects could be catastrophic.

Now your conclusions:

why 666 was not modified during it's major is a mystery - it should have been picked up on its pre-major survey
A mystery ? This aircraft had been flying for at least 10 years since the failure mode had been identified, it would have been through at least 2 major cycles. That would be 2 majors, 2 minor stars, 4 minors and 8 primary servicings, minimum, and you talk about pre-major surveys and mystery. I haven’t included engine changes. Following the accident the fleet was checked and others found with similar wiring problems, others too with the pre-mod starter motors fitted. So don’t talk about mystery. This was a failure of management, it was a failure of the airworthiness and safety management system. In typical fashion, the BOI does not pay proper attention to this.

In my humble opinion, Murphy's Law and Sod's Law creeps into this tragic XV230 incident
Murphy’s Law and Sod’s Law ? what kind of excuses are these ? As so many on here have debated, this situation seems to have been foreseeable. Certainly any reasonably robust safety analysis would have identified the hazards and the risks associated. You’ve even identified some of the failure modes yourself – possible early failure of seals etc due to exposure to excessive ambient temperatures. Yet you still refer to Murphy and Sod.

Please, leave the engineering to engineers !

S_H
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Old 10th Jul 2007, 00:11
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Safety Helmut,
I agree to some extent with your thoughts on the nut on the end of the starter motor on XV666. However, the failure of the nut was not the cause. The nut was/is/will never be expected, under normal conditions, to stop the turbine from coming off the end of the shaft. An automatic speed sensitive device is supposed to close off the air supply at an rpm below which the turbine would overstress the nut. Neither was it the speed sensitive device which failed. Within the same loom on the engine a live wire, operating the engine anti-icing valve (which had just been selected on) short circuited to the wire directly powering the air valve solenoid and bypassed the speed sensitive device. Therefore, the air valve opened, and remained open, and ran up the turbine, uncontrollably, to the point that the nut at the end of the shaft was stressed beyond its capabilities and the turbine came off. Its arguable whether or not a newer, or modified, nut would have retained the turbine, in that circumstance, but the fact is that the root cause was the short circuit bypassing the air valve control system.
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Old 10th Jul 2007, 05:57
  #846 (permalink)  
 
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ACOVEE:
Sir, with the greatest respect, it seems that you know little about current methodologies for Root Cause Analysis if you make the statement:
fact is that the root cause was the short circuit bypassing the air valve control system
From my reading of this thread, it seems that this was a known fault that was not dealt with. It would therefore lead me to believe that Safety Helmut has it absolutely right when he says that:
This was a failure of management
When the valve opened (or the nut failed) this would have been a first level causal factor.
Although it is a long time since I wore a blue uniform, it also seems clear from the various reports that I read here that BOIs are still failing to identify ‘Root Causes’ in the proper sense of the phrase.
Perhaps it is time to examine the BOI system.

Last edited by larssnowpharter; 10th Jul 2007 at 07:05.
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Old 10th Jul 2007, 06:50
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larssnowpharter

Spot on.

It is my understanding that BOIs are not permitted to make recommendations or comments concerning political policy. In the same way that, under the GEMS suggestions scheme, anything relating to MoD policy or politics is automatically rejected. (I once submitted a suggestion that funding should be made available to routinely maintain safety and airworthiness, and should be applied retrospectively. I cited examples of unsafe aircraft and equipment where the root cause was withdrawal of funding. It was thrown out. Still got my copy).

If you look at the BOI reports on any of the incidents mentioned here, none of them go far enough.
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Old 10th Jul 2007, 07:08
  #848 (permalink)  
 
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buoy15

Sir, might I just refer you to something you wrote earlier, where you said the following:

'which would illustrate to this audience the ramifications of a Captain making such a brief - ie - he would no longer be a Captain despite having the balls to protect his crew'

Now thereby lies perhaps the biggest problem that we have here. You are 100% correct with that statement, in that if you ever did 'scrub' a mission, your flying career would be over in days, if not hours.

There is the famous story of the E-3 Captain who scrubbed a Bosnia mission on the grounds that he and his crew were too tired, as they had been unable to sleep during the day due to building work in the hotel. He scrubbed on flight safety grounds and also to highlight the need for the blunties to relocate his crew to a 'quiet' hotel. The result was that he was removed from the fleet within a couple of weeks.

I would also agree entirely with you in your following statement:

'technology exists where a space the size of the Nimrod Bomb Bay could be overwhelmed with an inert gas (Halon) to douse a fire but that would involve weight, size and expense'

I think that is pretty much what I had said earlier about todays military aircraft being made as safe as possible. MR4 will not have a bomb bay fire suppressant for one reason only, and that is COST. Just because they are miltary aircraft, should not be a reason to deny them the latest kit to fight perhaps our greatest enemy in the air - FIRE. MR4 will no doubt have the very latest in electronics, avionics and goodness knows what else. I think that it should also have an up-to-date fire fighting system. Especially in an area where there have been problems in the past. I will refrain from commenting further on the AAR system.

Lastly Sir, Murpheys Law and Sods law do not exist in todays aviation world, not even in the military. We might have got away with them 10, 15 20 years ago, but not today. I doubt if you or I or indeed anyone would accept either of them as a just reason for the death of a loved one.
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Old 10th Jul 2007, 12:34
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I have held back for a while on this thread, but find I no longer can.
Winco, you state;
"Now thereby lies perhaps the biggest problem that we have here. You are 100% correct with that statement, in that if you ever did 'scrub' a mission, your flying career would be over in days, if not hours."
As an ex-MR2 captain I, and no doubt others reading your comments, feel insulted. Moreover, if you are insinuating that on the day of the tragic demise of XV230 the captain, known very well to me, didn't scrub because of his flying career, well, words cannot express my sentiments. Certainly nothing printable here.
I insist that you clarify.
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Old 10th Jul 2007, 12:43
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Betty,
Please explain why you are getting so irrate with my responce to what buoy15 said? Why are you not asking him to explain his comments to you?
The comments came from him Sir, NOT me. I was merely agreeing with him!

I did not suggest for a second or in any way that the captain of XV230 didn't scrub because of his career, and you should stop reading more into peoples' postings than is actually there.

I am also an ex MR2 captain, and I am well aware of the pressures on captains, especially in 'wartime' to complete the mission at all costs. That is not to say that anyone did or would, but as buoy15 says (another ex MR2 Captain) 'he would no longer be a Captain despite having the balls to protect his crew'

Might I suggest you direct your question to him and not me? Maybe he will be able to give you a more 'current' answer than me.
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Old 10th Jul 2007, 15:29
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Winco...
I'm not an angry young man, and not getting irate.
P'raps I'm missing the point, but I can't seem to find the quote from buoy15...
I'm just reading between the lines of what is said; maybe I have taken you out of context. If so, apologies...the last thing I want is a Winco/Wigan Warrier type exchange!

Having said that, I agree with his sentiments in waiting for the BOI. But I know I will get flak for saying this again.
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Old 10th Jul 2007, 15:54
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Betty,
No apologies needed Sir, I was simply agreeing with the comments from a fellow ex Nimrod Captain.
The Winco
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Old 10th Jul 2007, 19:58
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Winco, sorry, THE Winco

Glad to have you back on thread, I thought you might be sulking after being the only one to bite on the anonymous has-beens hook.

On a lighter note, I refused to fly last night because of chronic fatigue - does this mean I will get a dream ticket away from MR2 in the next 2 months?

CS
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Old 10th Jul 2007, 20:05
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Anoymous has-beens

Winco

You Know the saying:

If the (MOSS BROS) cap fits...
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Old 10th Jul 2007, 20:28
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camelspyyder
I understand you are not the only one who has refused to fly lately either.

Some one out in Afgahanistan also refused.
There must be an epidemic starting.
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Old 10th Jul 2007, 21:00
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Murphys / sods laws

The Winco, sorry, I don't agree with this
Lastly Sir, Murpheys Law and Sods law do not exist in todays aviation world, not even in the military. We might have got away with them 10, 15 20 years ago, but not today. I doubt if you or I or indeed anyone would accept either of them as a just reason for the death of a loved one
events based on the old Murphys / Sods laws do still occur, it is just that such events are now identified under 'human factors'.
DASC (and the CAA for our non-military bretheren) do some marvellous courses - get on them to see what is available to minimise these events happening, and to drive down the rate. Rarely does someone go to work to do a bad job, unhappily the errror rate is fairly constant. The major event rate is also fairly constant, as a % of all events.
If the growth in flying continues at the same rate as recently, with the same error rate, aviation - civilian and military -will be killing thousands more people each year. The challenge is to identify, track and eradicate errors by assisting people all through the chain of events to do so in an open 'no blame' culture. If / when someone makes an honest mistake they should be encouraged to own up to it in order to reduce the chances of a similar event being repeated. There is a place for a robust disciplinary system for abusers, thankfully 'we' don't have too many in the organisation.

Last edited by L1A2 discharged; 10th Jul 2007 at 21:02. Reason: spelling
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Old 10th Jul 2007, 21:25
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There is a place for a robust disciplinary system for abusers, thankfully 'we' don't have too many in the organisation
And when the abusers of the system are 4*, what place for them in your robust military system, LIA2?
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Old 10th Jul 2007, 21:55
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Chugalug2
Not sure I understand. Please explain. Thank you
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Old 11th Jul 2007, 06:38
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L1A2
Sir, I bow to your knowledge of the system but my problem is the same as Chugalug2 I think. I don't believe this is an aircrew problem, nor do I think it is a groundcrew/servicing problem.
The problem lies at the top of the RAF food chain, where very senior officers are out of touch with the reality of continually flying an aircraft that has passed the 'sell-by' date.

Aircraft Captains are reluctant to scrub for the reasons given earlier, and I have sympathy with that. Your comments about a 'no blame culture I would entirely agree with, but I think you are preaching to the converted here. There is nothing that will gain you more respect from your fellow aviators than standing up at a de-brief and saying 'sorry guys, I screwed up there, I made a mistake!' I

t takes an enormous amount of courage and humbleness to do that, even in front of colleagues and friends, but the rewards are equally large. I don't ever, in all my life, seem to recall a very senior officer standing up and saying 'sorry' for anything, does anyone else?

camelspyyder, I haven't really been away or sulking, I've just been a little more careful perhaps! I'm sorry you had to scrub last night, and I am genuingly concerned that you (and presumably your colleagues) are feeling that fatigued that you needed to canx. I'm not sure it will get you a ticket home or out of the fleet, but I'm certain your fellow aviators have even more respect for you than they did before. Did your Captain not notice the fatigue appearing within his crew? There's more to being a good Captain than just good flying and tactics. Perhaps he should go on one of those human factors courses? Do the Air Force still have such things or have they been canx also through lack of funds? Either way, I wish you well and hope you will be feeling better soon, and back on the front line. Best wishes

The Winco
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Old 11th Jul 2007, 07:38
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Not sure I understand. Please explain. Thank you
The question was short, and I thought, unambiguous. LIA2 mentioned the robustness of the "military system" while alluding to the civilian one. In the latter CEO's may, and sometimes have, acted inappropriately. The words "dirty" and "tricks" come to mind, for example. When exposed they invariably develop a strong desire to spend more time with their families and/or roses. What they cannot do, IMHO, is to interfere with the system of Flight Safety and Airworthiness, for that lays in the hands of a separate authority and beyond their control. No such arrangement, IMHO, protects your "robust military system". Hence my question re 4*s.

Last edited by Chugalug2; 11th Jul 2007 at 12:03. Reason: The right initials but not necessarily in the right order!
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