Nimrod crash in Afghanistan Tech/Info/Discussion (NOT condolences)
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Roland Pulfrew
an aircraft that was never airworthy in over 40 years
I suggest you watch this when Ainsworth said they were not airworthy as was proved, for many years
BBC NEWS | UK | Nimrods 'will not be grounded'
And then wipe the egg off your face !!
Has any action been taken against those with delegated responsibility for Nimrod airworthiness at the time of the Nimrod crash. As they failed in their duty?
No sir it has not, no demotions or court martial's 14 men killed through incompetence and someone is to blame.
Until I find out who was to blame I won't rest in my fight.
an aircraft that was never airworthy in over 40 years
which is blatent rubbish, despite what some non-expert coroner may have said.
BBC NEWS | UK | Nimrods 'will not be grounded'
And then wipe the egg off your face !!
I am not convinced by Knight's motives,
No sir it has not, no demotions or court martial's 14 men killed through incompetence and someone is to blame.
Until I find out who was to blame I won't rest in my fight.
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Nimrod Age
MadMark
Spanners
My apologies for the delay for getting back to you, but I have had a couple of days holiday and I purposely refrained from seeking out a computer to get logged on to Pprune! Nevertheless, as promised, I have spoken to some of our senior engineers at LHR and discussed the various points you raised, namely the Licensed engineers and also the checks for locating a fuel leak.
Let me explain the licensed engineers point firstly; and as I thought, you are quite wrong in your statement that unlicensed engineers ‘work’ on BA aircraft. They categorically DO NOT work on the aircraft, and for your information AGE (especially as I understand you are leaving the service soon) I am advised that this website will explain it all to you:
http://www.kingston.ac.uk/aircrafteng/licence/licence.htm
One of the chaps I met at LHR said that he was confident that he knew who you were (DG??) He was also at ISK and was going to get in touch with you.
On the business of locating fuel leaks, I am told by our engineers that there are currently a number of ways of locating a fuel leak. (none of which included buckets and soapy water and compressed air!) They involve ‘sniffer’ devices that are fed into the various areas where a leak is suspected and are used to locate the general area of the leak. (http://www.adixen.co.uk/downloads/Extrima-ENG.pdf) see page 2.
Litmus paper is then used to further narrow the exact location down. There is also some measuring equipment that is placed ‘in line’ within the fuel system to confirm firstly that there is a leak. I understand that the system is then pressurized to (I think they said 15lb psi) and a reading is then taken. After a set period of time, the reading is checked again, and if it has dropped then there is a leak. If it hasn’t then the system is OK. There are tolerances, but I don’t remember them. This method also helps in general location, as the pressurized system ‘forces’ out the fuel, thus staining the area of the leak.
(http://www.engineeringtalk.com/news/sis/sis105.html) This report highlights the importance of good leak detection, and in particular take note of the paragraph that states:
‘[FONT='Arial','sans-serif']Soap bubble testing can detect very small leaks allowing the operator to pinpoint the location of a leak. However, the process is highly dependent on the skill and patience of the operator. This can be dangerous if the operator's perspective is limited. For example, small leaks may remain hidden on the reverse side of the component or in a recess, which is a common occurrence in the aerospace industry where components are usually packed into tight spaces. [/FONT]
[FONT='Arial','sans-serif']Sometimes with soap bubble testing, larger leaks do not cause the formation of bubbles; instead, the compressed air blows away the soap solution, and operators frequently fail to observe such leaks.[/FONT]
[FONT='Arial','sans-serif']Conversely, with small holes, the capillary force can be extremely strong. [/FONT]
[FONT='Arial','sans-serif']The result is that liquid that has been sucked into a micro leak by capillary action, cannot be forced out with compressed air, and therefore no bubbles will appear. [/FONT]
[FONT='Arial','sans-serif']Another widely used leak detection method in the aerospace industry is pressure decay, where compressed air is simply injected into a test object, and a decrease in air pressure over time signifies a leak.[/FONT]
So, I can just confirm to you, that the practice of draining the fuel system down and then blowing air through it and listening for whistles, is NOT used on BA aircraft, and I would doubt that it is used on any other major airline.
That is still not to say that I blame you or any of your colleagues for what happened on 230, because I do not. But what you must try to appreciate (and it took me a long time to get my head around this also) is that the RAF is NOT the best at everything it does. It does NOT have the best kit available and does NOT (always) employ the best practices. I would suggest that perhaps you didn’t even know about these other methods of fuel leak detection did you? I am pretty sure that had you known about them, that someone at ISK would have suggested that you get one. But that would mean money, and thereby lies the root of this disaster – lack of money.
Now, and finally, as to whether or not you think I am a Walter Mitty or a real aircraft Captain flying a damned great aeroplane backwards and forwards across the pond with a few hundred pax behind me, I would simply respond by saying that frankly, I really couldn’t care less one way or another. You are free and entitled to make your own decision, and it affects not one thing in my life, it’s entirely yopur call Sirs.
[FONT='Calibri','sans-serif']But please, try to stop taking offence at everything that is said that remotely involves the groundcrew. IMHO they are NOT to blame at all for what happened to 230. The blame lies squarely on the shoulders of the government, then SoS, then CAS, ACAS, AOC, and probably the Station Commander, although I note that he did pass on his concerns up the chain.[/FONT]
[FONT='Calibri','sans-serif'][/FONT]
[FONT='Calibri','sans-serif']The Winco[/FONT]
MadMark
Spanners
My apologies for the delay for getting back to you, but I have had a couple of days holiday and I purposely refrained from seeking out a computer to get logged on to Pprune! Nevertheless, as promised, I have spoken to some of our senior engineers at LHR and discussed the various points you raised, namely the Licensed engineers and also the checks for locating a fuel leak.
Let me explain the licensed engineers point firstly; and as I thought, you are quite wrong in your statement that unlicensed engineers ‘work’ on BA aircraft. They categorically DO NOT work on the aircraft, and for your information AGE (especially as I understand you are leaving the service soon) I am advised that this website will explain it all to you:
http://www.kingston.ac.uk/aircrafteng/licence/licence.htm
One of the chaps I met at LHR said that he was confident that he knew who you were (DG??) He was also at ISK and was going to get in touch with you.
On the business of locating fuel leaks, I am told by our engineers that there are currently a number of ways of locating a fuel leak. (none of which included buckets and soapy water and compressed air!) They involve ‘sniffer’ devices that are fed into the various areas where a leak is suspected and are used to locate the general area of the leak. (http://www.adixen.co.uk/downloads/Extrima-ENG.pdf) see page 2.
Litmus paper is then used to further narrow the exact location down. There is also some measuring equipment that is placed ‘in line’ within the fuel system to confirm firstly that there is a leak. I understand that the system is then pressurized to (I think they said 15lb psi) and a reading is then taken. After a set period of time, the reading is checked again, and if it has dropped then there is a leak. If it hasn’t then the system is OK. There are tolerances, but I don’t remember them. This method also helps in general location, as the pressurized system ‘forces’ out the fuel, thus staining the area of the leak.
(http://www.engineeringtalk.com/news/sis/sis105.html) This report highlights the importance of good leak detection, and in particular take note of the paragraph that states:
‘[FONT='Arial','sans-serif']Soap bubble testing can detect very small leaks allowing the operator to pinpoint the location of a leak. However, the process is highly dependent on the skill and patience of the operator. This can be dangerous if the operator's perspective is limited. For example, small leaks may remain hidden on the reverse side of the component or in a recess, which is a common occurrence in the aerospace industry where components are usually packed into tight spaces. [/FONT]
[FONT='Arial','sans-serif']Sometimes with soap bubble testing, larger leaks do not cause the formation of bubbles; instead, the compressed air blows away the soap solution, and operators frequently fail to observe such leaks.[/FONT]
[FONT='Arial','sans-serif']Conversely, with small holes, the capillary force can be extremely strong. [/FONT]
[FONT='Arial','sans-serif']The result is that liquid that has been sucked into a micro leak by capillary action, cannot be forced out with compressed air, and therefore no bubbles will appear. [/FONT]
[FONT='Arial','sans-serif']Another widely used leak detection method in the aerospace industry is pressure decay, where compressed air is simply injected into a test object, and a decrease in air pressure over time signifies a leak.[/FONT]
So, I can just confirm to you, that the practice of draining the fuel system down and then blowing air through it and listening for whistles, is NOT used on BA aircraft, and I would doubt that it is used on any other major airline.
That is still not to say that I blame you or any of your colleagues for what happened on 230, because I do not. But what you must try to appreciate (and it took me a long time to get my head around this also) is that the RAF is NOT the best at everything it does. It does NOT have the best kit available and does NOT (always) employ the best practices. I would suggest that perhaps you didn’t even know about these other methods of fuel leak detection did you? I am pretty sure that had you known about them, that someone at ISK would have suggested that you get one. But that would mean money, and thereby lies the root of this disaster – lack of money.
Now, and finally, as to whether or not you think I am a Walter Mitty or a real aircraft Captain flying a damned great aeroplane backwards and forwards across the pond with a few hundred pax behind me, I would simply respond by saying that frankly, I really couldn’t care less one way or another. You are free and entitled to make your own decision, and it affects not one thing in my life, it’s entirely yopur call Sirs.
[FONT='Calibri','sans-serif']But please, try to stop taking offence at everything that is said that remotely involves the groundcrew. IMHO they are NOT to blame at all for what happened to 230. The blame lies squarely on the shoulders of the government, then SoS, then CAS, ACAS, AOC, and probably the Station Commander, although I note that he did pass on his concerns up the chain.[/FONT]
[FONT='Calibri','sans-serif'][/FONT]
[FONT='Calibri','sans-serif']The Winco[/FONT]
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Stop,stop,stop
Gentlemen,
Might I sugest that this e.mud-slinging is showing no-one in a particularly good light?
Might I also suggest that you all take a deep breath and count to 10...please?
Then, (forgiving and discounting a few hurtful remarks) perhaps it might be worth trying to see how the 'other parties' could be seeing this whole sad Nimrod episode and just maybe consider that, from their different point of view, it is understandable how the different people can feel the way they do?
If you could just try to imagine the hurt the families are going through, how hard engineers and crews are working at KSS/theatre and even how someone at the IPTs/DEC/MoD/Gp HQs are trying to get a quart of ambrosia out of the proverbial pint pot of p1ss. There may even be some pangs of guilt in some, or all, of the above.
Can you guys find something in this tragedy on which you can all agree?
For me, the real lesson from XV230 (and XV179) is that it illustrates how sorely underfunded are our Armed Forces?
Might I sugest that this e.mud-slinging is showing no-one in a particularly good light?
Might I also suggest that you all take a deep breath and count to 10...please?
Then, (forgiving and discounting a few hurtful remarks) perhaps it might be worth trying to see how the 'other parties' could be seeing this whole sad Nimrod episode and just maybe consider that, from their different point of view, it is understandable how the different people can feel the way they do?
If you could just try to imagine the hurt the families are going through, how hard engineers and crews are working at KSS/theatre and even how someone at the IPTs/DEC/MoD/Gp HQs are trying to get a quart of ambrosia out of the proverbial pint pot of p1ss. There may even be some pangs of guilt in some, or all, of the above.
Can you guys find something in this tragedy on which you can all agree?
For me, the real lesson from XV230 (and XV179) is that it illustrates how sorely underfunded are our Armed Forces?
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Here is the Ainsworth interview when he admits that the decision to claim the airworthiness status of Nimrod minutes after the Coroner's verdict was taken without any of his staff having heard the transcript of the Inquest, including himself. And he admits to a recent conversation with CAS but not immediately after the verdict was announced. And the 40 page conclusion had only just been read into court.
http://www.benknight.co.uk/BBC%20%20PM%20Programme.mp3
http://www.benknight.co.uk/BBC%20%20PM%20Programme.mp3
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Winco I thank you for your response, I know not who you refer to at LHA and he hasn't gotten in contact yet but I wait with anticipation.
In the meantime I am applying for an 'unlisenced' job at BA as I have looked at the following link:
BA Recruitment
Imagine my surprise, unlicensed mechanics and technicians working on BA aircraft, tut tut.
Know your own company??
In the meantime I am applying for an 'unlisenced' job at BA as I have looked at the following link:
BA Recruitment
Imagine my surprise, unlicensed mechanics and technicians working on BA aircraft, tut tut.
Know your own company??
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Umm,
technician and mechanic adverts carry the lines
and
which I think was the point Winco made in his last post? Surely rather than heading now into another round of
'engineers are licensed - no they're not - yes they are'
it might be an idea to look at the description of leak testing methodology and see if there's an improvement that can be made to current practise? ie take a somewhat heated argument and obtain something of worth from it?
Dave
technician and mechanic adverts carry the lines
, your work will always be inspected and signed off by a Licensed Aircraft Engineer.
Normally you would work alongside a Licensed Aircraft Engineer,
'engineers are licensed - no they're not - yes they are'
it might be an idea to look at the description of leak testing methodology and see if there's an improvement that can be made to current practise? ie take a somewhat heated argument and obtain something of worth from it?
Dave
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Good call, and should the RAF invest in some decent test equipment? And invest in enough sets so that it can be deployed with the aircraft?
One more thing. Before he signed off RP suggested that any compensation paid to the families would come out of the existing defence budget and that this would mean that soldiers would have to go to war without needed equipment as a result.
I understand that the MoD is intending to pay the families out of its own insurance policy designed for this purpose. I just wonder on what basis they are going to make the claim. If you do not have an MoT does that not invalidate the insurance?
Furthermore if Article 2 of HRA is upheld the British Govt would no longer be able to send its soldiers to their deaths in thin skinned Land Rovers.
There is a lot at stake here folks.
One more thing. Before he signed off RP suggested that any compensation paid to the families would come out of the existing defence budget and that this would mean that soldiers would have to go to war without needed equipment as a result.
I understand that the MoD is intending to pay the families out of its own insurance policy designed for this purpose. I just wonder on what basis they are going to make the claim. If you do not have an MoT does that not invalidate the insurance?
Furthermore if Article 2 of HRA is upheld the British Govt would no longer be able to send its soldiers to their deaths in thin skinned Land Rovers.
There is a lot at stake here folks.
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I quote from my post #1092
I think you may find that the guys who undertake the leak checks at BA are probably unlicensed and the job will be signed off by an ALE.
So I am therefore taking a stand back from this as requested and I am interested in the methods employed by BA.
Maybe someone at the IPT should contact BA and get engineering advice from them on how to keep our fleet flying as we seem to know nothing.
I think you may find that the guys who undertake the leak checks at BA are probably unlicensed and the job will be signed off by an ALE.
So I am therefore taking a stand back from this as requested and I am interested in the methods employed by BA.
Maybe someone at the IPT should contact BA and get engineering advice from them on how to keep our fleet flying as we seem to know nothing.
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All references to "reports" below and to Qinetiq (QQ) statements, unless otherwise stated, relate to:
"Nimrod Fuel System Safety Review Report", Oct 2007, Issue 1
The main conclusion of my last post was that contrary to several claims in this thread, this QQ report does not claim that the Nimrod fuel system was unsafe in its context of use and maintenance at the time the report was written. No one's written anything to suggest that conclusion was wrong.
Chugalug2:
The MoD is currently considering a separate MAA organisation but I doubt if they are seriously considering making it independent of the MoD. I don't know whether Chugalug2's claims hold water (no evidence is provided). Perhaps the idea of an independent MAA will be considered by Haddon-Cave's Nimrod Review:
http://www.nimrod-review.org.uk/
Distant Voice (DV) asked me:
No. But then I only know the issue history of one QQ Nimrod report (I've not bothered to check any others - I'm perfectly happy to accept DV's claim that they haven't been issued in draft for comment because it's just not an interesting aspect of this whole story).
JFZ90 wrote:
In my opinion, safety is just too important for any lapses in language and terminology to be acceptable. Ok, this thread doesn't, in itself, amount to much of a hill of beans, but formal QQ reports, etc. are another matter. My guess is that much of the farrago with authorities apparently making contradictory statements stems from the imprecise use of safety language and/or the use of undefined or misleading terms (like "tolerably safe").
davejb:
Absolutely, understood.
There is a "set of rules" but they are not being followed carefully (on this thread, by the MoD, by QQ, etc.). "Safety" feels like it should be a fairly straightforward thing to talk about. But it's not. Much of the blame for this rests with the ALARP principle. It looks so simple but, in general, its practical application is very difficult! The ALARP principle, as a means for determining the acceptability of risk, is contentious and has its critics (AFAIK, the only country in the world that uses it widely is the UK, it has been challenged in the European Court, etc.). In my opinion, the strongest argument against it is the complexities involved in applying it.
In my opinion, that's all too plausible.
Notwithstanding JFZ90's remarks about AAR, I agree with the thrust of what davejb is saying. Strongly!
Not really. The MoD's definition of safe (which is always relative to a context of use and maintainance) requires that risks are ALARP. However, it is entirely possible for the risk of flying an aircraft to be ALARP in a context of use that does not include, for example, AAR, but not ALARP in a context of use that does.
Think of your own car. In some sense, it is "safe" if driven in accordance with the rules of the road and properly maintained. Now suppose you never maintain it or MoT it, and/or drive it at 100 mph through crowded playgrounds. Same car ... but is it safe now?
Safeware wrote:
I don't really know what point Safeware is making here. Perhaps you could clarify, Safeware? E.g., when you use the term "unacceptable", are you using it in the generic English language sense, or in the defined risk management sense (POSMS, Def Stan 00-56, etc.). And are you defining the term "acceptable" accordingly?
One of the problems of safety management terminology is that a set of terms has grown up that has very specific meaning in safety/risk management but distinctly different meanings in general English language. Two very relevant examples are "unacceptable" and "tolerable". It leads to confusions whereby risks can be "tolerable" in the risk management sense but "intolerable" in the generic English sense. And risks can be "unacceptable" in the generic English sense but not "unacceptable" in the risk management sense (hence my question above to Safeware). I wish we (the UK) could junk such risk/safety management terminology and replace it with something better thought out but it's probably too late now.
Anyway, I firmly believe that QQ are using the word "acceptable", in:
in its generic, English dictionary sense (they certainly don't provide any other definition and I'm not aware of one in any relevant safety/risk management documents, e.g., POSMS, 00-56, HSE guidance, etc. - all suggesting QQ are using the term in its generic English sense).
That's the same sense the word is used in:
1. HSE guidance - see, for example, Reducing Risks, Protecting People:
http://www.hse.gov.uk/risk/theory/r2p2.htm
(Incidentally, Safety Helmut's claim that, "Acceptable and tolerable are used pretty much interchangably" in R2P2 is wrong - see, for example, pages 3 & 8 which address the issue very specifically)
2. the MoD's Safety Management bible, POSMS (see, for example, SMP07, clause 10.1.5):
http://www.asems.mod.uk/posms_manual.htm
And if QQ are using the term, "acceptable" in its generic sense, then the only criterion I know of by which they could make a judgement that a risk is acceptable is that the risk is either "broadly acceptable", or "tolerable" and ALARP. Certainly, QQ give no other criterion in the report and I am aware of no other criterion defined by relevant safety/risk management documents, e.g., POSMS, 00-56, HSE guidance, etc., suggesting that they mean that the risk is either "broadly acceptable", or "tolerable" and ALARP. Hence, they are saying that at the time they wrote the report, the Nimrod fuel system was safe in its then context of use and maintenance.
Final point on this. Whatever QQ meant when they wrote:
it doesn't affect the validity of my claim that QQ's statement:
is not referring to the context of use and maintenance of the aircraft current at the time the report was written. Thus, the QQ report does not claim that the Nimrod fuel system was unsafe in its context of use and maintenance extant at the time the report was written.
DV wrote:
As with Safeware's post, I'm not sure what point DV is trying to make here. I'm not sure what the "square one" that DV refers to is. Do you, DV, mean to equate the "tolerable" you found in the dictionary with "tolerable" in the safety/risk management sense (see, e.g., POSMS, 00-56, R2P2, etc.)? To do so would be a mistake because they have very different meanings (see my para. above).
AFAIK, they're not. What's the relevance of the question?
KeepItTidy:
Hardly!
"Nimrod Fuel System Safety Review Report", Oct 2007, Issue 1
The main conclusion of my last post was that contrary to several claims in this thread, this QQ report does not claim that the Nimrod fuel system was unsafe in its context of use and maintenance at the time the report was written. No one's written anything to suggest that conclusion was wrong.
Chugalug2:
The bottom line is very simple, the present arrangement allows for the operator (the MOD) to be its own regulator. The result has been the farrago exposed in this and the Parliamentary Questions threads. Self regulation does not work. In aviation it does not work in a spectacular and devastating way. Forget the MOD's "Efforts", nothing short of an independant Military Airworthiness Authority will suffice.
http://www.nimrod-review.org.uk/
Distant Voice (DV) asked me:
Can you give an example of another Nimrod related report [that was released by Qinetiq (QQ) in draft for comment]?
JFZ90 wrote:
I've resisted criticising the QQ report in the way you have, but the weaknesses/inconsistences you point out are spot on. In their defence you could argue they would not have expected particular phrases to have been latched onto in the way they have without consideration of the wider picture you outline.
davejb:
I would like to emphasise however that the points from my own post that you have quoted were very much questions, rather than statements
my basic problem being I keep expecting there to be a set of rules by which a system is declared ok or not. Instead it seems to be a mental Gordian knot.
My feeling is that sometime post '82 an approach of 'it's been okay so far' was substituted for rigorous safety procedures, and that has been exacerbated by declining experience levels in just about every trade, including aircrew.
personally I don't think that an AAR system failure almost 25 years later says much good of the safety management of Nimrod, surely in all that time it could have been given a thorough going over to check it was really okay?
ALARP - I believe I get the basic idea, I also believe (perhaps wrongly) it is possible to fly the aircraft safely without it being ALARP, provided AAR isn't performed (for example)
Think of your own car. In some sense, it is "safe" if driven in accordance with the rules of the road and properly maintained. Now suppose you never maintain it or MoT it, and/or drive it at 100 mph through crowded playgrounds. Same car ... but is it safe now?
Safeware wrote:
I haven't yet gone through the report but one of the points you make is not quite correct.
Quote:
If QQ are saying that the risks are (currently) "acceptable", then they are saying they are ALARP.
Doesn't actually hold.
If some thing is "acceptable", it doesn't mean that the risks are ALARP, it means that the risks can be accepted, ie only that they are not "unacceptable"
Quote:
If QQ are saying that the risks are (currently) "acceptable", then they are saying they are ALARP.
Doesn't actually hold.
If some thing is "acceptable", it doesn't mean that the risks are ALARP, it means that the risks can be accepted, ie only that they are not "unacceptable"
One of the problems of safety management terminology is that a set of terms has grown up that has very specific meaning in safety/risk management but distinctly different meanings in general English language. Two very relevant examples are "unacceptable" and "tolerable". It leads to confusions whereby risks can be "tolerable" in the risk management sense but "intolerable" in the generic English sense. And risks can be "unacceptable" in the generic English sense but not "unacceptable" in the risk management sense (hence my question above to Safeware). I wish we (the UK) could junk such risk/safety management terminology and replace it with something better thought out but it's probably too late now.
Anyway, I firmly believe that QQ are using the word "acceptable", in:
The current operating limitations imposed by SD and the additional maintenance activities invokeds through RTIs mitigate the fuel system risks to acceptable levels. Changes to such mitigating action must be supported by appropriate evidence
That's the same sense the word is used in:
1. HSE guidance - see, for example, Reducing Risks, Protecting People:
http://www.hse.gov.uk/risk/theory/r2p2.htm
(Incidentally, Safety Helmut's claim that, "Acceptable and tolerable are used pretty much interchangably" in R2P2 is wrong - see, for example, pages 3 & 8 which address the issue very specifically)
2. the MoD's Safety Management bible, POSMS (see, for example, SMP07, clause 10.1.5):
http://www.asems.mod.uk/posms_manual.htm
And if QQ are using the term, "acceptable" in its generic sense, then the only criterion I know of by which they could make a judgement that a risk is acceptable is that the risk is either "broadly acceptable", or "tolerable" and ALARP. Certainly, QQ give no other criterion in the report and I am aware of no other criterion defined by relevant safety/risk management documents, e.g., POSMS, 00-56, HSE guidance, etc., suggesting that they mean that the risk is either "broadly acceptable", or "tolerable" and ALARP. Hence, they are saying that at the time they wrote the report, the Nimrod fuel system was safe in its then context of use and maintenance.
Final point on this. Whatever QQ meant when they wrote:
The current operating limitations imposed by SD [Service Deviation] and the additional maintenance activities invokeds through RTIs [Routine Technical Instructions] mitigate the fuel system risks to acceptable levels. Changes to such mitigating action must be supported by appropriate evidence
"the recommendations [...] should be considered and acted upon, where appropriate, before it can be considered that the equipment risks are ALARP"
DV wrote:
If you look up "acceptable" in the Concise Oxford Dictionary it say that it means "tolerable". So we are back to square one. It is just that "acceptable" gives a better (but false) impression of safety
As with Safeware's post, I'm not sure what point DV is trying to make here. I'm not sure what the "square one" that DV refers to is. Do you, DV, mean to equate the "tolerable" you found in the dictionary with "tolerable" in the safety/risk management sense (see, e.g., POSMS, 00-56, R2P2, etc.)? To do so would be a mistake because they have very different meanings (see my para. above).
You mention Def Stan 00-56, can you tell me where the terms "acceptable" and "tolerably safe" are defined in that document?
KeepItTidy:
So this entire thread and discussion is down to a meaning in the English dictionary when we refer to Tolerable or acceptable taken in the worng way ?
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RAF Techie you asked about whistle tests, this is an account of evidence presented on 21 May. Usual cautions apply, this is not necessarily word for word, but was written down at the time, by someone I trust implicitly.
Rawlinson. The list of mitigations was to convert ac that was unairworthy into airworthy? Yes. That was by limiting some operating circumstances? yes. Crossfeeed pipe not used in flt? Correct.
Inspection every 30 days. Fuel couplings, elec systems for arcing. What chks on fuel system? Ev 30 days fuel system pressurised to 50psi with full tanks - pressurised by bowser. Ac level.
C- how do you chk for leaks? Depanel the ac and look. It’s the same test we’d do if we had repaced a fuel component.
Fuel coupling inspection (rib3 to rib3) and part replacement. Replace targteed fuel seals. This has come about after the Qinetiq investigation. Replace 40 seals in high risk areas - that’s to say where a leaking coupling wd hazard the ac.
C - suggests FRS couplings are unsuitable. Gp Capt doesn’t understand why they are not suitable. C says it’s because they dry out if not in contact with fuel.
Gp Capt says he takes his advice on that from the ac designer. (as opposed to the coupling manufacturer)
C - Qinetiq report says these seals deteriorate in 5 days if not in contact with fuel? It’s their advice you shd take? It’s a matter for the ac designer. Have you discussed it with them? Only in offline discussions. What was result? Not answered
C these couplings may turn out to be usnuitable? My point is that the mnfr wants these couplings, and it’s up to them.
Can you say this risk has been mitigated? And is it airworthy? we’ve done these checks and there’s an RTI. (Routine Technical Instruction, I think)
C - With this evidence how can you say you’ve mitigated? - this inquest needs to know what steps you’ve taken.
I understand. If the ac mnfr so decides , we’ll change the couplings.
C--should the ac be flying until this is sorted? I don’t follow that argument. We’ve seen leaks before.
C - (The coupling) manufacturer says they’re unsuitable couplings. Does your offline discussion (with ac mnfr) say they are? No they don’t. The hazard from fuel leaks in vent system is just a fuel leak. Not desirable, but a fuel leak on a nimrod shd not put it on the ground.
C- If the vent pipe passes throught the fuselage into the wg, then it’s a risk? - it’s unsafe? Yes, but following that incident we carried out an RTI to check the integrity - we did pressure chks on vent system. We blow air through it and examine for leaks.
Our reaction to leaks thro the vent system was to introduce a checking system by blowing air through it. Do you use soapy water like with a bicycle tyre? Yes. And we listen for hissing air. Done in hangar. We cease all other maint work while this is going on, so they can hear whistling of leaks.
Rawlinson You are sounding to the families as if you have a very casual attitude? No. I have no casual attitude to airworthiness.
What about reported leaks - some aircraft have as many as 11? Correct
A small number of those are due to misaligned pipes at the coupling? yes. What are you doing about that? It’s part of 30-day chks (that we’ve instigated as one of the mitigations.) It’s done by eye.
The manufacturer says misalignment is the no 1 cause of leaks? - and the maintenance guy said have you any idea how difficult it is to do this alignment above yr head? It’’s difficult. 1º misalignment is impossible to detect.
C- so seals are not the major prob? It’s alignment? Yes, but, gross misalignment will be found,
C In the video that we’ve all seen, what caused that leak? Don’t know. How can the IPT not know about that? We’ve had others.
C- what reasons? Incorrect assembly of ccoupling - no, sorry, scrub that.
C - was it to do with FRS seals? One was incorrect alignment, others had damage to seal, damaged during fitting inside coupling. Those are the only two I recall. But we have investigated several. What was front runner? Alignment.
Rawlinson Can technicians get physical access to all couplings withing venting system? Not all of them. How do you test those you can’t get at? If you can’t see them, you can hear the leaks. You’d need a techie to answer that. What is dist between hearer and the parts that can’t be reached? Can’t answer. But how can you satisfy yourself abour airwrthiness if there are clear areaa where you can’t be sure? That’s why we introduced full comprehensive tests to get a acess to all. That’s only annually? Yes. But where you have a seal that can dry out (in 5 days) and you’re only chkg every 30 days, how does that work? We do it as far as poss every 30 days, then follow up annually. But these mitigation steps were to say that an ac that was not airworthy is now so? - surely we can’t be sure, because you can’t chk them all, and you can’t give us enough detail to assure us it’s safe? I believe we have mitigated (the risks)
How do you know this leaking fuel isn’t in contact with ignition source? We know it leaks, and our strategy is to ensure the ac can tolerate leaks.
C - there are hot sources and electrical soureces? yes. Eg APU, plus electrical sources? yes there is a risk of fuel leaks onto an electrical component.. The advice from Qinetiq on electrical arcing at altitude is that it is unlikely to be a risk. Once ac is airborne, sparking is unlikely at altitude.
C-- But the ac has to get up there? yes. You satisfied with that? yes. Our independent fuel safety review redid the analysis. They said ac is tolerably safe to fly. This is not ALARP? Qinetiq says it’s tolerably safe, but not yet ALARP. .
C - Talking about JSP553 (Mil Airworthiness manual) - your predecessor as the ITPL, Air Cdre Baber, agreed that the requirement was to reduce risk to ALARP. Can you confirm that this ac is not ALARP? Yes. We are checking fuel couplings and replacing them. We’re replacing hot air ducts. But we haven’t done that yet so it’s not ALARP.
Rawlinson. The list of mitigations was to convert ac that was unairworthy into airworthy? Yes. That was by limiting some operating circumstances? yes. Crossfeeed pipe not used in flt? Correct.
Inspection every 30 days. Fuel couplings, elec systems for arcing. What chks on fuel system? Ev 30 days fuel system pressurised to 50psi with full tanks - pressurised by bowser. Ac level.
C- how do you chk for leaks? Depanel the ac and look. It’s the same test we’d do if we had repaced a fuel component.
Fuel coupling inspection (rib3 to rib3) and part replacement. Replace targteed fuel seals. This has come about after the Qinetiq investigation. Replace 40 seals in high risk areas - that’s to say where a leaking coupling wd hazard the ac.
C - suggests FRS couplings are unsuitable. Gp Capt doesn’t understand why they are not suitable. C says it’s because they dry out if not in contact with fuel.
Gp Capt says he takes his advice on that from the ac designer. (as opposed to the coupling manufacturer)
C - Qinetiq report says these seals deteriorate in 5 days if not in contact with fuel? It’s their advice you shd take? It’s a matter for the ac designer. Have you discussed it with them? Only in offline discussions. What was result? Not answered
C these couplings may turn out to be usnuitable? My point is that the mnfr wants these couplings, and it’s up to them.
Can you say this risk has been mitigated? And is it airworthy? we’ve done these checks and there’s an RTI. (Routine Technical Instruction, I think)
C - With this evidence how can you say you’ve mitigated? - this inquest needs to know what steps you’ve taken.
I understand. If the ac mnfr so decides , we’ll change the couplings.
C--should the ac be flying until this is sorted? I don’t follow that argument. We’ve seen leaks before.
C - (The coupling) manufacturer says they’re unsuitable couplings. Does your offline discussion (with ac mnfr) say they are? No they don’t. The hazard from fuel leaks in vent system is just a fuel leak. Not desirable, but a fuel leak on a nimrod shd not put it on the ground.
C- If the vent pipe passes throught the fuselage into the wg, then it’s a risk? - it’s unsafe? Yes, but following that incident we carried out an RTI to check the integrity - we did pressure chks on vent system. We blow air through it and examine for leaks.
Our reaction to leaks thro the vent system was to introduce a checking system by blowing air through it. Do you use soapy water like with a bicycle tyre? Yes. And we listen for hissing air. Done in hangar. We cease all other maint work while this is going on, so they can hear whistling of leaks.
Rawlinson You are sounding to the families as if you have a very casual attitude? No. I have no casual attitude to airworthiness.
What about reported leaks - some aircraft have as many as 11? Correct
A small number of those are due to misaligned pipes at the coupling? yes. What are you doing about that? It’s part of 30-day chks (that we’ve instigated as one of the mitigations.) It’s done by eye.
The manufacturer says misalignment is the no 1 cause of leaks? - and the maintenance guy said have you any idea how difficult it is to do this alignment above yr head? It’’s difficult. 1º misalignment is impossible to detect.
C- so seals are not the major prob? It’s alignment? Yes, but, gross misalignment will be found,
C In the video that we’ve all seen, what caused that leak? Don’t know. How can the IPT not know about that? We’ve had others.
C- what reasons? Incorrect assembly of ccoupling - no, sorry, scrub that.
C - was it to do with FRS seals? One was incorrect alignment, others had damage to seal, damaged during fitting inside coupling. Those are the only two I recall. But we have investigated several. What was front runner? Alignment.
Rawlinson Can technicians get physical access to all couplings withing venting system? Not all of them. How do you test those you can’t get at? If you can’t see them, you can hear the leaks. You’d need a techie to answer that. What is dist between hearer and the parts that can’t be reached? Can’t answer. But how can you satisfy yourself abour airwrthiness if there are clear areaa where you can’t be sure? That’s why we introduced full comprehensive tests to get a acess to all. That’s only annually? Yes. But where you have a seal that can dry out (in 5 days) and you’re only chkg every 30 days, how does that work? We do it as far as poss every 30 days, then follow up annually. But these mitigation steps were to say that an ac that was not airworthy is now so? - surely we can’t be sure, because you can’t chk them all, and you can’t give us enough detail to assure us it’s safe? I believe we have mitigated (the risks)
How do you know this leaking fuel isn’t in contact with ignition source? We know it leaks, and our strategy is to ensure the ac can tolerate leaks.
C - there are hot sources and electrical soureces? yes. Eg APU, plus electrical sources? yes there is a risk of fuel leaks onto an electrical component.. The advice from Qinetiq on electrical arcing at altitude is that it is unlikely to be a risk. Once ac is airborne, sparking is unlikely at altitude.
C-- But the ac has to get up there? yes. You satisfied with that? yes. Our independent fuel safety review redid the analysis. They said ac is tolerably safe to fly. This is not ALARP? Qinetiq says it’s tolerably safe, but not yet ALARP. .
C - Talking about JSP553 (Mil Airworthiness manual) - your predecessor as the ITPL, Air Cdre Baber, agreed that the requirement was to reduce risk to ALARP. Can you confirm that this ac is not ALARP? Yes. We are checking fuel couplings and replacing them. We’re replacing hot air ducts. But we haven’t done that yet so it’s not ALARP.
Nige:
Thankyou for the long post, my problem with Winco's statement was his inference that
IS undertaken on Nimrods.
This practice is undertaken with VENT lines, not fuel lines, as your post proves. To check the fuel lines with air would be non-sensical. People argue that the vent lines can contain fuel, and yes - they can. However, this is in the form of vapour, as the vent lines are blown through continually during flight, as the name would suggest. This is then blown overboard next to the jettison points.
Thankyou for the long post, my problem with Winco's statement was his inference that
the practice of draining the fuel system down and then blowing air through it and listening for whistles, is NOT used on BA aircraft
This practice is undertaken with VENT lines, not fuel lines, as your post proves. To check the fuel lines with air would be non-sensical. People argue that the vent lines can contain fuel, and yes - they can. However, this is in the form of vapour, as the vent lines are blown through continually during flight, as the name would suggest. This is then blown overboard next to the jettison points.
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Oh Dear, MightyHunter AGE,
There you go yet again! - this sad, pathetic 'little boy' attitude when you don't get your own way. For goodness sake man, do grow up a bit and try to stop all this ridiculous points scoring stupidity.
Forget about licensed engineers and all that nonesence and concentrate on the important matters here. The hard fact is that at ISK (and probably elsewhere in the RAF) you DO NOT use up-to-date kit to locate fuel leaks do you? You use a method that we have all used for years when we have had a puncture on our bikes! Unfortunately, as has been proven and shown (in my last posting) this is NOT reliable, and should not be used. ENDEX
I re-iterate that the probable reason for the lack of modern kit is lack of money. It's as simple as that. It's not your fault, its not OC Eng's fault, and its probably not even the Staish's fault. Its down to the constant cuts in the defence budget and lack of investment. So accept that, and stop trying to make excuses for everything.
It will become abundantly clear to you when you join BA, that things are done much differently outside, and in the main they are done much better.
Good luck with your application.
RAF Techie 101. I am fairly certain that somewhere in the past few pages, someone claimed that the fuel system on NImrods was checked for leaks by draining it and using compressed air. Indeed, I think that was one of the points that the EATON corporation commented on about the seals drying out wasn't it? Anyway, the point I was trying to make is that there are other, better, and more accurate methods of locating and identifying aircraft fuel leaks other than soapy water, and the same goes for the vents also.
There you go yet again! - this sad, pathetic 'little boy' attitude when you don't get your own way. For goodness sake man, do grow up a bit and try to stop all this ridiculous points scoring stupidity.
Forget about licensed engineers and all that nonesence and concentrate on the important matters here. The hard fact is that at ISK (and probably elsewhere in the RAF) you DO NOT use up-to-date kit to locate fuel leaks do you? You use a method that we have all used for years when we have had a puncture on our bikes! Unfortunately, as has been proven and shown (in my last posting) this is NOT reliable, and should not be used. ENDEX
I re-iterate that the probable reason for the lack of modern kit is lack of money. It's as simple as that. It's not your fault, its not OC Eng's fault, and its probably not even the Staish's fault. Its down to the constant cuts in the defence budget and lack of investment. So accept that, and stop trying to make excuses for everything.
It will become abundantly clear to you when you join BA, that things are done much differently outside, and in the main they are done much better.
Good luck with your application.
RAF Techie 101. I am fairly certain that somewhere in the past few pages, someone claimed that the fuel system on NImrods was checked for leaks by draining it and using compressed air. Indeed, I think that was one of the points that the EATON corporation commented on about the seals drying out wasn't it? Anyway, the point I was trying to make is that there are other, better, and more accurate methods of locating and identifying aircraft fuel leaks other than soapy water, and the same goes for the vents also.
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Winco please.
I did try and give you the benefit of the doubt but your last post has again made me chuckle.
It took you so long to reply to me before as you were searching the internet like anyone desperate to justify their argument. I could search all day long and find the same but to be honest I cant be bothered.
Have fun on Flight Sim 2000.
I did try and give you the benefit of the doubt but your last post has again made me chuckle.
It took you so long to reply to me before as you were searching the internet like anyone desperate to justify their argument. I could search all day long and find the same but to be honest I cant be bothered.
Have fun on Flight Sim 2000.
RAFTechie101 states: This practice is undertaken with VENT lines, not fuel lines, as your post proves. To check the fuel lines with air would be non-sensical. People argue that the vent lines can contain fuel, and yes - they can. However, this is in the form of vapour, as the vent lines are blown through continually during flight, as the name would suggest. This is then blown overboard next to the jettison points.
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Softie, is it significant that this test equipment is not available in theatre? I am thinking back to the serious fuel leaks where it was not possible to replicate on the ground. Is it possible that;
a. This equipment is available at Kinloss?
b. This equipment is not available to deployed aircraft and could not be used after fuel leak events in theatre?
This has been a point of confusion for some time,
Regards,
Nige
a. This equipment is available at Kinloss?
b. This equipment is not available to deployed aircraft and could not be used after fuel leak events in theatre?
This has been a point of confusion for some time,
Regards,
Nige
Nig
No, it is not significant. Should a serious leak be found in theatre, the aircraft and tanks concerned would be restricted/limited and flown back to UK for repair. If this is not possible or unsafe then a team and equipment would be deployed. This is no different from any other RAF fleet. Major work at a deployed base (of any type) is not desirable because of the lack of backup resources and expertise.
No, it is not significant. Should a serious leak be found in theatre, the aircraft and tanks concerned would be restricted/limited and flown back to UK for repair. If this is not possible or unsafe then a team and equipment would be deployed. This is no different from any other RAF fleet. Major work at a deployed base (of any type) is not desirable because of the lack of backup resources and expertise.
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Gentlemen,
A few complaints have been made regarding the off topic, abuse, mud slinging and.....it goes on.
One or two of you have had their posts deleted for good reason and included in the above.
We are not going to tolerate this. Some of you have been close to a ban on this thread so I strongly suggest that you wind necks in and concentrate on a debate constructed from real knowledge and understanding.
Btw. Toys and prams are strictly forbidden too!
PPP
A few complaints have been made regarding the off topic, abuse, mud slinging and.....it goes on.
One or two of you have had their posts deleted for good reason and included in the above.
We are not going to tolerate this. Some of you have been close to a ban on this thread so I strongly suggest that you wind necks in and concentrate on a debate constructed from real knowledge and understanding.
Btw. Toys and prams are strictly forbidden too!
PPP
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Squidlord, you wrote
What I was trying to get at, without getting into the arguments of "official safety" or "dictionary" meanings, was what an IPT will look for. This report doesn't provide definitions, which does occur in Release To Service Recommendations, but I don't think that is important at this stage.
In essence, and I'll use a range of words to cover differing angles and people's experiences, the question for the IPT is "is the problem UNACCEPTABLE/ is the risk INTOLERABLE" ie "is there something that it is ESSENTIAL to do to mitigate the risk?" If it isn't, then it is by inference, acceptable (whether this be Tolerable, Acceptable, Broadly Acceptable, Unsatisfactory or Satisfactory), ie it can be accepted. However, just because it can be accepted, doesn't make it ALARP (even unacceptable/intolerable risks can be accepted in exceptional circumstances (and I know that this may seem to contradict my earlier "ie only that they are not "unacceptable", but I was trying to be 'general' and describe the norm there)).
IPTs really don't like things that are Unacceptable or Intolerable (or the phrase Release To Service is not recommended) because it means that they have to do something about it (even if it is just justifying what they want to do to someone up the chain) and life isn't going to be as simple as they wanted. They *will* exert pressure on QQ not to use such words.
Of course, in the strictest sense, even an Intolerable Risk could be ALARP, since there may be nothing more that can be done. In "exceptional circumstances" you would want to demonstrate that even at that level of risk, you had done everything you could to reduce the risk as far as you could, it may just not be practicable to reduce it further. This shows that ALARP is about the practicality of risk reduction and tolerability about the willingness to bear that risk. The link between the 2 being the "sacrifice" ("sacrifice" wrt App 3, para 4 of R2P2) required to be made.
Some people want to discuss the meanings in great detail, I wasn't, only trying to point out that whatever words were being used, in anyone's books "acceptable" doesn't equal ALARP, as you inferred.
sw
Safeware wrote:
I haven't yet gone through the report but one of the points you make is not quite correct.
Quote:
If QQ are saying that the risks are (currently) "acceptable", then they are saying they are ALARP.
Doesn't actually hold.
If some thing is "acceptable", it doesn't mean that the risks are ALARP, it means that the risks can be accepted, ie only that they are not "unacceptable"
I don't really know what point Safeware is making here. Perhaps you could clarify, Safeware? E.g., when you use the term "unacceptable", are you using it in the generic English language sense, or in the defined risk management sense (POSMS, Def Stan 00-56, etc.). And are you defining the term "acceptable" accordingly?
I haven't yet gone through the report but one of the points you make is not quite correct.
Quote:
If QQ are saying that the risks are (currently) "acceptable", then they are saying they are ALARP.
Doesn't actually hold.
If some thing is "acceptable", it doesn't mean that the risks are ALARP, it means that the risks can be accepted, ie only that they are not "unacceptable"
I don't really know what point Safeware is making here. Perhaps you could clarify, Safeware? E.g., when you use the term "unacceptable", are you using it in the generic English language sense, or in the defined risk management sense (POSMS, Def Stan 00-56, etc.). And are you defining the term "acceptable" accordingly?
In essence, and I'll use a range of words to cover differing angles and people's experiences, the question for the IPT is "is the problem UNACCEPTABLE/ is the risk INTOLERABLE" ie "is there something that it is ESSENTIAL to do to mitigate the risk?" If it isn't, then it is by inference, acceptable (whether this be Tolerable, Acceptable, Broadly Acceptable, Unsatisfactory or Satisfactory), ie it can be accepted. However, just because it can be accepted, doesn't make it ALARP (even unacceptable/intolerable risks can be accepted in exceptional circumstances (and I know that this may seem to contradict my earlier "ie only that they are not "unacceptable", but I was trying to be 'general' and describe the norm there)).
IPTs really don't like things that are Unacceptable or Intolerable (or the phrase Release To Service is not recommended) because it means that they have to do something about it (even if it is just justifying what they want to do to someone up the chain) and life isn't going to be as simple as they wanted. They *will* exert pressure on QQ not to use such words.
Of course, in the strictest sense, even an Intolerable Risk could be ALARP, since there may be nothing more that can be done. In "exceptional circumstances" you would want to demonstrate that even at that level of risk, you had done everything you could to reduce the risk as far as you could, it may just not be practicable to reduce it further. This shows that ALARP is about the practicality of risk reduction and tolerability about the willingness to bear that risk. The link between the 2 being the "sacrifice" ("sacrifice" wrt App 3, para 4 of R2P2) required to be made.
Some people want to discuss the meanings in great detail, I wasn't, only trying to point out that whatever words were being used, in anyone's books "acceptable" doesn't equal ALARP, as you inferred.
sw
Last edited by Safeware; 1st Jul 2008 at 15:25. Reason: spooling and sense of 'unacceptable/intolerable and ALARP