Nimrod crash in Afghanistan Tech/Info/Discussion (NOT condolences)
Join Date: Jun 2008
Location: Kinloss
Posts: 99
Likes: 0
Received 0 Likes
on
0 Posts
What are the outstanding risks?
Everyone is missing the point:
Hickman indicated that fuel couplings and (active) hot pipe replacements are the only outstanding projects that need to be completed to make the risk ALARP. The fact of the matter is that the active hot pipes are all in engine fire zones, which makes the extant risk acceptable (better than tolerable). If you are involved with aviation you will know that all large jet aircraft around the World have hot air pipes in their engine zones. Its an aviation standard acceptable risk if there is adequate fire protection in place. We have that protection on the Nimrod. If any of those old ducts burst, we will detect the failure and deal with it, within seconds of the failure. Although they need to be replaced due to age, which will reduce the risk of duct failure to ALARP, this is work that is above the safety line. It does not need to be done to make the aircraft safe, or even safer, to fly. I can assure all Nimrod aircrew and their families that the ducts in question are in the engine bays and are subject to failure detection systems: gas leak detectors and fire wire. Do not allow yourself to be convinced otherwise by people here who do not know the aircraft and are seeking to prove their point by legal argument only. Sure, Gp Capt Hickman should have represented these facts better and his words are now being analyzed, but whatever might be written here, the duct replacement program is not relevant to airworthiness.
The seal replacement project is work above the safety line. It does not need to be done to make the aircraft safe, or safer, to fly. Obviously, replacing a 25 year old seal will reduce the risk of that seal failing to ALARP and this is what the Gp Capt indicated. But, do we need to change all the old seals to make the aircraft airworthy? This is the question at the heart of the discussion. It is not a question that TD, DAForce, NG, DV, Winco, the Coroner, Rawlinson and Evans are qualified to answer. It is unfortunate that the man who should be qualified to answer, allowed himself to be drawn into JSP553 definitions rather than focusing on what needs to be done or, more to point, what has been done, to make the aircraft safe. The reason why the seals do not need to be replaced to make the aircraft safe is because they were originally manufactured to last forever. I listened very carefully to what the seal company man said about his seals. If they are not disturbed, they will not leak. The company placed a 25 year life on the seals after the accident. If the accident did not happen those seals would still be un-lifed. In any case if any coupling leaks outside a fire zone, for whatever reason (misalignment, flexing, dry then wet) the consequence will not be catestrophic because there is nothing (except for a co-incident and undetected massive electrical failure) outside a fire zone that will cause the leaked fuel to ignite.
The Nimrod is safer today than it has ever been.
Regards
Ed Sett
PS. Winco, As aircrew, I am not familiar with the equipment used by the technicians to test for fuel leaks.
GP CAPT HICKMAN: Yes. I am stating that the aircraft is tolerably safe but is not yet ALARP because there are a number of measures we have yet to take to reduce the risk to as low as reasonably practicable, we have not taken them yet.
THE CORONER: Yes, I just wanted to clear that up. What are these other matters, these areas you have not taken yet?
GP CAPT HICKMAN: There are several, but the major ones are the semi fuel coupling inspection and replacement has to be conducted on every aircraft. In addition, we want to replace the hot air ducts that are still used, that are still hot, and have not been switched off. Now, these are measures we need to take to reduce the risk and we have not taken them yet and therefore we are not ALARP.
THE CORONER: Yes, I just wanted to clear that up. What are these other matters, these areas you have not taken yet?
GP CAPT HICKMAN: There are several, but the major ones are the semi fuel coupling inspection and replacement has to be conducted on every aircraft. In addition, we want to replace the hot air ducts that are still used, that are still hot, and have not been switched off. Now, these are measures we need to take to reduce the risk and we have not taken them yet and therefore we are not ALARP.
The seal replacement project is work above the safety line. It does not need to be done to make the aircraft safe, or safer, to fly. Obviously, replacing a 25 year old seal will reduce the risk of that seal failing to ALARP and this is what the Gp Capt indicated. But, do we need to change all the old seals to make the aircraft airworthy? This is the question at the heart of the discussion. It is not a question that TD, DAForce, NG, DV, Winco, the Coroner, Rawlinson and Evans are qualified to answer. It is unfortunate that the man who should be qualified to answer, allowed himself to be drawn into JSP553 definitions rather than focusing on what needs to be done or, more to point, what has been done, to make the aircraft safe. The reason why the seals do not need to be replaced to make the aircraft safe is because they were originally manufactured to last forever. I listened very carefully to what the seal company man said about his seals. If they are not disturbed, they will not leak. The company placed a 25 year life on the seals after the accident. If the accident did not happen those seals would still be un-lifed. In any case if any coupling leaks outside a fire zone, for whatever reason (misalignment, flexing, dry then wet) the consequence will not be catestrophic because there is nothing (except for a co-incident and undetected massive electrical failure) outside a fire zone that will cause the leaked fuel to ignite.
The Nimrod is safer today than it has ever been.
Regards
Ed Sett
PS. Winco, As aircrew, I am not familiar with the equipment used by the technicians to test for fuel leaks.
Join Date: Jul 2002
Location: UK Sometimes
Posts: 1,062
Likes: 0
Received 0 Likes
on
0 Posts
"tolerably safe"
For those dealing in semantics, it might interest you to know that there is, in fact, a reference to 'tolerably safe'.
The term is definitely not one of the standard definitions but I have found reference in Def Stan 00-56 at Part 2, Annex B, para B.1.4 d) which expands upon the risk assessment process.
Taking the Annex as whole, the term 'tolerably safe' infers Tolerable and ALARP - which we believe the Nimrod will not achieve until next year (despite the contradictory words in Westminster).
What I can't find in 00-56 is guidance for when something is not safe (either broadly acceptable or tolerable and ALARP). Also, I can't find reference to say that the Safety Management System has a certain time to rectify the problem, just that if a risk is assessed outside the above criteria, it cannot be tolerated except in exceptional circumstances.
Therefore, one might argue that the coroner was right to recommend the fleet be grounded (I don't believe that will be operationally acceptable, however - and neither would the PBI (poor bl**dy infantry) on the ground in AFG.)
However, I agree that in the civvie world, it is 'common practice' to give identified risks a certain amount of time to be rectified - but one might argue that even that is not 'good practice' (see Annex B)!
Anyone know where this common assumption and practice is defined?
The term is definitely not one of the standard definitions but I have found reference in Def Stan 00-56 at Part 2, Annex B, para B.1.4 d) which expands upon the risk assessment process.
Taking the Annex as whole, the term 'tolerably safe' infers Tolerable and ALARP - which we believe the Nimrod will not achieve until next year (despite the contradictory words in Westminster).
What I can't find in 00-56 is guidance for when something is not safe (either broadly acceptable or tolerable and ALARP). Also, I can't find reference to say that the Safety Management System has a certain time to rectify the problem, just that if a risk is assessed outside the above criteria, it cannot be tolerated except in exceptional circumstances.
Therefore, one might argue that the coroner was right to recommend the fleet be grounded (I don't believe that will be operationally acceptable, however - and neither would the PBI (poor bl**dy infantry) on the ground in AFG.)
However, I agree that in the civvie world, it is 'common practice' to give identified risks a certain amount of time to be rectified - but one might argue that even that is not 'good practice' (see Annex B)!
Anyone know where this common assumption and practice is defined?
Last edited by flipster; 4th Jul 2008 at 11:29.
Join Date: Sep 2006
Location: Bridgwater Somerset
Posts: 459
Likes: 0
Received 0 Likes
on
0 Posts
Ed Sett
You said:
Transcript
GP CAPT HICKMAN: Okay. There’s two parts to this programme. It’s a fuel coupling inspection and a chartered fuel seal replacement programme. This is the first part is one of the recommendations from the Board of Inquiry that we do a detailed inspection of all fuel couplings, rib 3 to rib 3, for correct alignment, assembly and locking. So the first part of that programme will be conducted during equalised maintenance on every aircraft. The first one has been completed, and it’s exactly that to check the fuel couplings. It’s an inspection a detailed inspection.
But the second part is a targeted fuel seal replacement, which is a result of the QinetiQ fuel system safety review, which identified the most hazardous areas of the aircraft which would arise should there be a fuel leak. So, what we’ve effectively chosen to do is replace the fuel seals in those high risk areas. There are 40 such couplings where we have targeted a fuel seal replacement, the end being to reduce that hazard by ensuring that we have a brand new at least a brand new series, not a brand new coupling in that area.
THE CORONER: Forty seals in a high risk area?
GP CAPT HICKMAN: Yes.
THE CORONER: Forty couplings with seals?
GP CAPT HICKMAN: Yes.
MR RAWLINSON: Can I just explore with you for a moment how those 40 had been identified? Are they identified as high risk because if they fail they create a high risk, or are they identified as being at high risk of failure?
GP CAPT HICKMAN: They are the couplings which, if they leak, most hazard the aircraft.
MR EVANS: (MOD Solicitor) We have been through the various mitigation measures put in place and I do not want to repeat them unnecessarily, but I think one did not come out.
In addition to the targeted placement of seals that you have instituted under the technical instruction and the 40 critical seals that were replaced, every five years 180 of the 400 seals in the aeroplane are also replaced in addition to that 40.
So thats why the seals need changing then Ed Sett they are in a high risk area. But worry not they will be done by June next year.
You said:
But, do we need to change all the old seals to make the aircraft airworthy? This is the question at the heart of the discussion. It is not a question that TD, DAForce, NG, DV, Winco, the Coroner, Rawlinson and Evans are qualified to answer.
GP CAPT HICKMAN: Okay. There’s two parts to this programme. It’s a fuel coupling inspection and a chartered fuel seal replacement programme. This is the first part is one of the recommendations from the Board of Inquiry that we do a detailed inspection of all fuel couplings, rib 3 to rib 3, for correct alignment, assembly and locking. So the first part of that programme will be conducted during equalised maintenance on every aircraft. The first one has been completed, and it’s exactly that to check the fuel couplings. It’s an inspection a detailed inspection.
But the second part is a targeted fuel seal replacement, which is a result of the QinetiQ fuel system safety review, which identified the most hazardous areas of the aircraft which would arise should there be a fuel leak. So, what we’ve effectively chosen to do is replace the fuel seals in those high risk areas. There are 40 such couplings where we have targeted a fuel seal replacement, the end being to reduce that hazard by ensuring that we have a brand new at least a brand new series, not a brand new coupling in that area.
THE CORONER: Forty seals in a high risk area?
GP CAPT HICKMAN: Yes.
THE CORONER: Forty couplings with seals?
GP CAPT HICKMAN: Yes.
MR RAWLINSON: Can I just explore with you for a moment how those 40 had been identified? Are they identified as high risk because if they fail they create a high risk, or are they identified as being at high risk of failure?
GP CAPT HICKMAN: They are the couplings which, if they leak, most hazard the aircraft.
MR EVANS: (MOD Solicitor) We have been through the various mitigation measures put in place and I do not want to repeat them unnecessarily, but I think one did not come out.
In addition to the targeted placement of seals that you have instituted under the technical instruction and the 40 critical seals that were replaced, every five years 180 of the 400 seals in the aeroplane are also replaced in addition to that 40.
So thats why the seals need changing then Ed Sett they are in a high risk area. But worry not they will be done by June next year.
Last edited by Tappers Dad; 4th Jul 2008 at 15:20. Reason: inclusion of the word not in the last sentence
Join Date: Mar 2006
Location: wilts
Posts: 1,667
Likes: 0
Received 0 Likes
on
0 Posts
whistle while you work
If that is right Flip, IPTL referred to tolerably safe meaning tolerable and ALARP at the same time as admitting that Nimrod is not ALARP and that they were working towards a goal of the majority of mitigations implemented by the end of the year? Confused? I am.
Regarding whistle tests I think this clears it up once and for all;
GP CAPT HICKMAN: Well, we do check the integrity of the vent system. The vent system is primarily designed for air, and we’ve introduced an RTI which checks the system for leaks, so we in addition to the other checks I’ve talked about, we check the integrity.
THE CORONER: Were you here when we heard evidence yesterday from the maintenance personnel, that an aircraft, whilst being refuelled as part of maintenance, sat at 2 degrees, had fuel coming through a vent system, which we now know, from the manufacturer and your offline discussions, is an unsuitable coupling? You can see why members of the families start to become concerned. Putting these pieces of evidence together is not a matter which is difficult. It does not require an expert, but it may require action. What counsel is testing is what action has been taken. For example, as these pieces of evidence have fallen out from this inquest, what steps have been taken to try to recognise any hazard and mitigate any risk?
GP CAPT HICKMAN: Yes. No, I understand the point. What I’m saying is that we would if we are saying that if the aircraft designer does advise that they agree that FRS couplings are unsuitable for the vent system, then we will absolutely yes, of course we will take action.
THE CORONER: But this would surely mean that the aircraft should not fly until that has been rectified. The difficulty is that here we are having a discussion about whether they are suitable or not, and the aircraft still flies. Surely the safest point is to ensure that this discussion has come to an end with a conclusion, before aircraft fly?
GP CAPT HICKMAN: Well, I don’t accept that. I don’t quite follow that argument. Your argument is that
THE CORONER: Let me put it simply. Evidence exists from the maintenance team that, on a routine maintenance, fuel came out through a vent system.
GP CAPT HICKMAN: Yes.
THE CORONER: The manufacturer has stood in court and given evidence on oath that these are unsuitable seals; these couplings are unsuitable for a vent system.
GP CAPT HICKMAN: Yes.
THE CORONER: Your offline discussions indicate they also may be unsuitable.
GP CAPT HICKMAN: No, they haven’t. Sorry, the offline discussions have not indicated that.
THE CORONER: What have they indicated?
GP CAPT HICKMAN: That we well, I think that there’s some work to do to decide whether they are or not for designers to advise whether they are or not.
THE CORONER: Do you not feel, therefore, that a question needs to be asked whether or not, in the light of these pieces of evidence when they stand together, this aircraft should, at least in the short term, have its flying duties curtailed?
GP CAPT HICKMAN: No. No, I don’t, because the what you’re suggesting at the moment is that fuel could leak from the vent system. I think that we’ve already established or I hope that we’ve already established that we do get fuel leaks on the aircraft, so what I contend is that the hazard from what you’re describing from a fuel vent system seal leaking fuel when fuel may enter the vent system is a fuel leak. And clearly that’s undesirable and we will clearly take action to mitigate that hazard, absolutely. But a fuel leak on a Nimrod wouldn’t result in a grounding, because if that was the case then we would have we wouldn’t be able to fly at all because, as you have heard, we have had fuel leaks.
MR RAWLINSON: Forgive me, but I understood Sergeant Whitmore to say that a Nimrod with a fuel leak in the fuselage does not fly; that is fixed. This is the other problem with this, that what undermines the system
THE CORONER: Just to put the point clearly, if the vent system passes from the fuselage into the wings, then with an unsuitable coupling in the vent system there is a risk of a leak in the fuselage and the aircraft would not fly.
GP CAPT HICKMAN: If we if we in fact, if we found a leak in the vent system, it would be fixed.
THE CORONER: Yes, but what we are saying is the evidence suggests that the couplings are unsuitable, and the evidence suggests that the seal would degrade in a very short period of time, making the system unsafe. So the only time in a vent system you would see a leak is if the vent system finished displacing all the air and started to displace fuel, which we have seen, in a test carried out as part of maintenance, does occur in the aircrafts on the ground.
GP CAPT HICKMAN: Yes, but what I was going to say was following that incident, we have carried out RTIs to check the integrity and the sealing of the vent system.
THE CORONER: How? Do you take them apart?
GP CAPT HICKMAN: We pressure check them.
THE CORONER: You pressure check the vent system?
GP CAPT HICKMAN: Yes, with air.
THE CORONER: How do you pressure test the vent system with air. What, do you put a cork in one end? How do you do it?
GP CAPT HICKMAN: Effectively, we apply a ground air rig to the vent system and we pressurise it.
THE CORONER: Do you pressurise it or do you blow air through it?
GP CAPT HICKMAN: Yes, we blow air through it and then we examine it for leaks.
THE CORONER: How would you see an air leak?
GP CAPT HICKMAN: Well, as it was described to me by a tradesman who had found a leak, by a whistling sound.
THE CORONER: I see, by a whistling sound.
GP CAPT HICKMAN: Yes.
THE CORONER: And the tradesman found a leak?
GP CAPT HICKMAN: Yes, he did, yes.
THE CORONER: Whereabouts?
GP CAPT HICKMAN: I don’t recall.
THE CORONER: And yet you maintain, despite all this body of evidence suggesting that there could possibly be because of the degradation of the seals because they are in contact with air which you incidentally are blowing through the system to test it that this might not create a risk of fuel leaking in the fuselage?
GP CAPT HICKMAN: No, I think, you know, our reaction to the certainly the risk of leaks from the vent system and to that incident that we heard about earlier during a ground refuel, was to introduce a routine technical instruction to check the vent system for leaks.
THE CORONER: By blowing air through it.
GP CAPT HICKMAN: By blowing air through it at high pressure.
THE CORONER: And therefore degrading the seals?
GP CAPT HICKMAN: We don’t believe so, no. Our strategy is to pressurise it with air and look for leaks.
THE CORONER: Push air though it while listening for a whistling sound?
GP CAPT HICKMAN: Yes.
THE CORONER: The old way was to take some soapy water and run it around a joint and see if it bubbles. At least, that is what you used to use to discover a leak in the inner tube of your bicycle tyre.
GP CAPT HICKMAN: Yes, and we do a similar test, a soap test, yes.
THE CORONER: You do a soap test as well?
GP CAPT HICKMAN: It can be yes, you can do that, but that’s not
THE CORONER: That is not what you do, but you can do.
GP CAPT HICKMAN: No, we don’t. We don’t call up we don’t call that up. It is a test, as I’ve described, listening for air leaks, because the pressure of the air means that you can hear the leaks.
THE CORONER: Is this done in the open air or in the hangar?
GP CAPT HICKMAN: In the hangar, normally, yes.
THE CORONER: Do you instruct that all other maintenance work is ceased while you listen for the whistling?
GP CAPT HICKMAN: Yes.
THE CORONER: I see.
MR RAWLINSON: Can I just continue with this. Do your technicians call for absolute silence during these tests?
GP CAPT HICKMAN: I don’t know.
MR RAWLINSON: Do you have any scientific or recent evidence of assuring ourselves that the whistle will be heard if it is produced?
GP CAPT HICKMAN: Well, all I can say is I have anecdotal evidence from tradesmen that they have located leaks by hearing whistling, yes.
MR RAWLINSON: I have secretly (inaudible) you throughout the entire duration of this hearing, trying to inject a combative note where one was not needed, but you can understand why the families might gain the impression that the evidence that you give shows a certain casualness of attitude. You understand that, don’t you?
GP CAPT HICKMAN: No. I would have to say that if you are suggesting that I have a casual attitude to airworthiness, then, no, I don’t.
MR RAWLINSON: How many leaks have been detected since XV230 within the fuel pumps?
GP CAPT HICKMAN: We introduced following the accident, we introduced mandatory reporting of fuel leaks, so that all fuel leaks from the fuselage, from fuel couplings and the incidents where fuel is found collected in any areas on the aircraft is reported. We’ve had, from that, the data shows 111 fuel leaks.
Regarding whistle tests I think this clears it up once and for all;
GP CAPT HICKMAN: Well, we do check the integrity of the vent system. The vent system is primarily designed for air, and we’ve introduced an RTI which checks the system for leaks, so we in addition to the other checks I’ve talked about, we check the integrity.
THE CORONER: Were you here when we heard evidence yesterday from the maintenance personnel, that an aircraft, whilst being refuelled as part of maintenance, sat at 2 degrees, had fuel coming through a vent system, which we now know, from the manufacturer and your offline discussions, is an unsuitable coupling? You can see why members of the families start to become concerned. Putting these pieces of evidence together is not a matter which is difficult. It does not require an expert, but it may require action. What counsel is testing is what action has been taken. For example, as these pieces of evidence have fallen out from this inquest, what steps have been taken to try to recognise any hazard and mitigate any risk?
GP CAPT HICKMAN: Yes. No, I understand the point. What I’m saying is that we would if we are saying that if the aircraft designer does advise that they agree that FRS couplings are unsuitable for the vent system, then we will absolutely yes, of course we will take action.
THE CORONER: But this would surely mean that the aircraft should not fly until that has been rectified. The difficulty is that here we are having a discussion about whether they are suitable or not, and the aircraft still flies. Surely the safest point is to ensure that this discussion has come to an end with a conclusion, before aircraft fly?
GP CAPT HICKMAN: Well, I don’t accept that. I don’t quite follow that argument. Your argument is that
THE CORONER: Let me put it simply. Evidence exists from the maintenance team that, on a routine maintenance, fuel came out through a vent system.
GP CAPT HICKMAN: Yes.
THE CORONER: The manufacturer has stood in court and given evidence on oath that these are unsuitable seals; these couplings are unsuitable for a vent system.
GP CAPT HICKMAN: Yes.
THE CORONER: Your offline discussions indicate they also may be unsuitable.
GP CAPT HICKMAN: No, they haven’t. Sorry, the offline discussions have not indicated that.
THE CORONER: What have they indicated?
GP CAPT HICKMAN: That we well, I think that there’s some work to do to decide whether they are or not for designers to advise whether they are or not.
THE CORONER: Do you not feel, therefore, that a question needs to be asked whether or not, in the light of these pieces of evidence when they stand together, this aircraft should, at least in the short term, have its flying duties curtailed?
GP CAPT HICKMAN: No. No, I don’t, because the what you’re suggesting at the moment is that fuel could leak from the vent system. I think that we’ve already established or I hope that we’ve already established that we do get fuel leaks on the aircraft, so what I contend is that the hazard from what you’re describing from a fuel vent system seal leaking fuel when fuel may enter the vent system is a fuel leak. And clearly that’s undesirable and we will clearly take action to mitigate that hazard, absolutely. But a fuel leak on a Nimrod wouldn’t result in a grounding, because if that was the case then we would have we wouldn’t be able to fly at all because, as you have heard, we have had fuel leaks.
MR RAWLINSON: Forgive me, but I understood Sergeant Whitmore to say that a Nimrod with a fuel leak in the fuselage does not fly; that is fixed. This is the other problem with this, that what undermines the system
THE CORONER: Just to put the point clearly, if the vent system passes from the fuselage into the wings, then with an unsuitable coupling in the vent system there is a risk of a leak in the fuselage and the aircraft would not fly.
GP CAPT HICKMAN: If we if we in fact, if we found a leak in the vent system, it would be fixed.
THE CORONER: Yes, but what we are saying is the evidence suggests that the couplings are unsuitable, and the evidence suggests that the seal would degrade in a very short period of time, making the system unsafe. So the only time in a vent system you would see a leak is if the vent system finished displacing all the air and started to displace fuel, which we have seen, in a test carried out as part of maintenance, does occur in the aircrafts on the ground.
GP CAPT HICKMAN: Yes, but what I was going to say was following that incident, we have carried out RTIs to check the integrity and the sealing of the vent system.
THE CORONER: How? Do you take them apart?
GP CAPT HICKMAN: We pressure check them.
THE CORONER: You pressure check the vent system?
GP CAPT HICKMAN: Yes, with air.
THE CORONER: How do you pressure test the vent system with air. What, do you put a cork in one end? How do you do it?
GP CAPT HICKMAN: Effectively, we apply a ground air rig to the vent system and we pressurise it.
THE CORONER: Do you pressurise it or do you blow air through it?
GP CAPT HICKMAN: Yes, we blow air through it and then we examine it for leaks.
THE CORONER: How would you see an air leak?
GP CAPT HICKMAN: Well, as it was described to me by a tradesman who had found a leak, by a whistling sound.
THE CORONER: I see, by a whistling sound.
GP CAPT HICKMAN: Yes.
THE CORONER: And the tradesman found a leak?
GP CAPT HICKMAN: Yes, he did, yes.
THE CORONER: Whereabouts?
GP CAPT HICKMAN: I don’t recall.
THE CORONER: And yet you maintain, despite all this body of evidence suggesting that there could possibly be because of the degradation of the seals because they are in contact with air which you incidentally are blowing through the system to test it that this might not create a risk of fuel leaking in the fuselage?
GP CAPT HICKMAN: No, I think, you know, our reaction to the certainly the risk of leaks from the vent system and to that incident that we heard about earlier during a ground refuel, was to introduce a routine technical instruction to check the vent system for leaks.
THE CORONER: By blowing air through it.
GP CAPT HICKMAN: By blowing air through it at high pressure.
THE CORONER: And therefore degrading the seals?
GP CAPT HICKMAN: We don’t believe so, no. Our strategy is to pressurise it with air and look for leaks.
THE CORONER: Push air though it while listening for a whistling sound?
GP CAPT HICKMAN: Yes.
THE CORONER: The old way was to take some soapy water and run it around a joint and see if it bubbles. At least, that is what you used to use to discover a leak in the inner tube of your bicycle tyre.
GP CAPT HICKMAN: Yes, and we do a similar test, a soap test, yes.
THE CORONER: You do a soap test as well?
GP CAPT HICKMAN: It can be yes, you can do that, but that’s not
THE CORONER: That is not what you do, but you can do.
GP CAPT HICKMAN: No, we don’t. We don’t call up we don’t call that up. It is a test, as I’ve described, listening for air leaks, because the pressure of the air means that you can hear the leaks.
THE CORONER: Is this done in the open air or in the hangar?
GP CAPT HICKMAN: In the hangar, normally, yes.
THE CORONER: Do you instruct that all other maintenance work is ceased while you listen for the whistling?
GP CAPT HICKMAN: Yes.
THE CORONER: I see.
MR RAWLINSON: Can I just continue with this. Do your technicians call for absolute silence during these tests?
GP CAPT HICKMAN: I don’t know.
MR RAWLINSON: Do you have any scientific or recent evidence of assuring ourselves that the whistle will be heard if it is produced?
GP CAPT HICKMAN: Well, all I can say is I have anecdotal evidence from tradesmen that they have located leaks by hearing whistling, yes.
MR RAWLINSON: I have secretly (inaudible) you throughout the entire duration of this hearing, trying to inject a combative note where one was not needed, but you can understand why the families might gain the impression that the evidence that you give shows a certain casualness of attitude. You understand that, don’t you?
GP CAPT HICKMAN: No. I would have to say that if you are suggesting that I have a casual attitude to airworthiness, then, no, I don’t.
MR RAWLINSON: How many leaks have been detected since XV230 within the fuel pumps?
GP CAPT HICKMAN: We introduced following the accident, we introduced mandatory reporting of fuel leaks, so that all fuel leaks from the fuselage, from fuel couplings and the incidents where fuel is found collected in any areas on the aircraft is reported. We’ve had, from that, the data shows 111 fuel leaks.
Join Date: Mar 2006
Location: wilts
Posts: 1,667
Likes: 0
Received 0 Likes
on
0 Posts
Yea it is almost funny, Ainsworth now tells us Nimrod is after all ALARP airworthy safe tickety boo, and no-one demurs from this view, QQ, BAe, RAF, IPT, the cleaner etc etc, however buried deep in Hickman's evidence;
GP CAPT HICKMAN: No. I will clarify. The aircraft is, and the QinetiQ report says this, the QinetiQ report says the aircraft is tolerably safe but is not yet ALARP, and I would agree.
No need to worry, letters winging their way around the non-demurrers, is that really a word? Will retire from the fight for a while.
Nice weekend to everyone. Couple of questions to Edsett. Edsett you are keen to warn off the families from questioning the safety of Nimrod post XV230.
Why is it that Poseidon P8A has fuel tank protection, dry bay protection, bomb bay protection, flight deck armour etc etc and MRA4 has none of this?
Why is it that dry bay protection was spec'd for Nimrod back in 1981 and never fitted?
Why should we back off?
GP CAPT HICKMAN: No. I will clarify. The aircraft is, and the QinetiQ report says this, the QinetiQ report says the aircraft is tolerably safe but is not yet ALARP, and I would agree.
No need to worry, letters winging their way around the non-demurrers, is that really a word? Will retire from the fight for a while.
Nice weekend to everyone. Couple of questions to Edsett. Edsett you are keen to warn off the families from questioning the safety of Nimrod post XV230.
Why is it that Poseidon P8A has fuel tank protection, dry bay protection, bomb bay protection, flight deck armour etc etc and MRA4 has none of this?
Why is it that dry bay protection was spec'd for Nimrod back in 1981 and never fitted?
Why should we back off?
Join Date: Mar 2007
Location: Bristol Temple Meads
Posts: 869
Likes: 0
Received 0 Likes
on
0 Posts
Ed Sett 100, re your 1266
So now you have your own standard "acceptable is better than tolerable". Where did that come from?
ALARP is the safety line, and the hot air system is still not safe.
I am sorry but it is you who is misleading aircrew and families, with regards to duct failures. We are now replacing some 37 ducts in the engine bay and cross-feed systems, most of which were identified by BAE Systems in early 2005 (after the XV227 duct failure) as being life expired and in need of replacement.
A duct failure in engine bay area is classed as REMOTE CATASTOPHIC. Check you hazard log. And before you go any further on mitigation, a fire detection and suppression system simply buys you time. In QQ's words it does not mitigate the hazard. To do that you have to switch off the system.
So now we have two systems that are not ALARP, the fuel system and the hot air system. Any more?
DV
So now you have your own standard "acceptable is better than tolerable". Where did that come from?
Although they [ducts] need to be replaced due to old age, which will reduce the duct failure to ALARP, this is work that is above the safety line
I am sorry but it is you who is misleading aircrew and families, with regards to duct failures. We are now replacing some 37 ducts in the engine bay and cross-feed systems, most of which were identified by BAE Systems in early 2005 (after the XV227 duct failure) as being life expired and in need of replacement.
A duct failure in engine bay area is classed as REMOTE CATASTOPHIC. Check you hazard log. And before you go any further on mitigation, a fire detection and suppression system simply buys you time. In QQ's words it does not mitigate the hazard. To do that you have to switch off the system.
So now we have two systems that are not ALARP, the fuel system and the hot air system. Any more?
DV
Join Date: Nov 2006
Location: Kinloss
Posts: 78
Likes: 0
Received 0 Likes
on
0 Posts
Winco in responce to post 1258 I cannot at this time comment as I am no longer an AGE at Kinloss having left in November.
Due to this it would be wrong of me to comment on the current equipment being used as it may have been updated since my leaving some 7 months ago.
You see I know when to be quiet when my knowledge is not up to date.
I was leaving this to rest but you seem keen to persue me.
Do you want me to ridicule you again on your lack of understanding of aviation engineering practices in your own company. I refer you to my post #1109
MHAGE
Due to this it would be wrong of me to comment on the current equipment being used as it may have been updated since my leaving some 7 months ago.
You see I know when to be quiet when my knowledge is not up to date.
I was leaving this to rest but you seem keen to persue me.
Do you want me to ridicule you again on your lack of understanding of aviation engineering practices in your own company. I refer you to my post #1109
MHAGE
Join Date: Apr 2006
Location: Back in Geordie Land
Posts: 492
Likes: 0
Received 0 Likes
on
0 Posts
MightyHunter AGE,
Well, as someone who has portrayed themselves as being pretty well knowledgeable on the MR2, I am dissapointed that you are now declining to comment on a quite simple request. I don't claim to know about engineering practices, which is why I have asked people who claim to be the 'experts' - like you for example.
As it is only 7 months since you left, you could have at least commented on what was being used when you were current on the fleet, and as this is well within the period of interest here, I wonder why you have declined??? Hmm, maybe you don't know eh? maybe you arn't even an AGE after all!!
I don't mind you ridiculing me over my lack of engineering knowledge at all. The fact is,I'm NOT an engineer!! I'm a pilot!
Now if you want some info about flying, then I'll gladly help you out, you just let me know what you want, and I'll do my best to help. One thing is certain - I wouldn't ridicule you for not knowing say the approach speed or the flap limitation speed for a B747.
Well, as someone who has portrayed themselves as being pretty well knowledgeable on the MR2, I am dissapointed that you are now declining to comment on a quite simple request. I don't claim to know about engineering practices, which is why I have asked people who claim to be the 'experts' - like you for example.
As it is only 7 months since you left, you could have at least commented on what was being used when you were current on the fleet, and as this is well within the period of interest here, I wonder why you have declined??? Hmm, maybe you don't know eh? maybe you arn't even an AGE after all!!
I don't mind you ridiculing me over my lack of engineering knowledge at all. The fact is,I'm NOT an engineer!! I'm a pilot!
Now if you want some info about flying, then I'll gladly help you out, you just let me know what you want, and I'll do my best to help. One thing is certain - I wouldn't ridicule you for not knowing say the approach speed or the flap limitation speed for a B747.
Join Date: Aug 2007
Location: St Annes
Age: 69
Posts: 638
Likes: 0
Received 0 Likes
on
0 Posts
The argument about ALARP and 'time to achieve ALARP' will doubtless run and run, with polarised views continuing, one camp failing to persuade the other as per the previous billion posts. As others have pointed out most of us on here simply don't have the depth of knowledge of engineering or of the legal profession to be confident of which way the cookie is really crumbling.
So - I think the MOD/RAF have a duty to ensure that current aircrew are happy that they are flying an airworthy aircraft. It may be that aircrew are privvy to extra reassurance over and above what has been seen in the public domain, I hope so because the public utterances from MOD/Minister/RAF APPEAR to me to lack consistency, and they don't impress me as reassuring. In fact mostly it looks remarkably like spin, I would have thought it obvious for any competent bunch to at least agree to say the same thing as each other - right or wrong, there's a kind of perception of truth if you say the same thing repeatedly, consistently, and loud enough....they haven't managed that even. 'They' should move heaven and earth to convince people it's safe, and to my mind they've managed far less than that so far.
I still don't see why pipe and seal integrity isn't tested by pressurising then monitoring the pressure over a reasonable period, any leak will appear as a fall in pressure - wouldn't that 'just' require access to each end of a section and a suitable gas, say nitrogen, to fill it with? Wouldn't this be a more certain test than listening for leaks? It was noticeable during Gp Capt Hickman's grilling - and that does look to be adversarial to me, and I can quite understand how he might well have floundered a bit under attack - but his evidence citing the 'whistling sound' as a valid test amounted to groundcrew had done this and found leaks thereby - which is the worst kind of error in my book...all he knows from that is SOME leaks are found this way, he has no idea if dozens more are missed!
Oh, and I think Winco IS a pilot, it would be more convincing to point out flaws in his description of the leak testing than to continue this 'you aren't a pilot because you didn't answer fast enough ' bolleux...had he been trawling the internet for info he'd have had it posted within hours. Go for the ball* chaps, not the man.
Dave
*as opposed to the plural.
So - I think the MOD/RAF have a duty to ensure that current aircrew are happy that they are flying an airworthy aircraft. It may be that aircrew are privvy to extra reassurance over and above what has been seen in the public domain, I hope so because the public utterances from MOD/Minister/RAF APPEAR to me to lack consistency, and they don't impress me as reassuring. In fact mostly it looks remarkably like spin, I would have thought it obvious for any competent bunch to at least agree to say the same thing as each other - right or wrong, there's a kind of perception of truth if you say the same thing repeatedly, consistently, and loud enough....they haven't managed that even. 'They' should move heaven and earth to convince people it's safe, and to my mind they've managed far less than that so far.
I still don't see why pipe and seal integrity isn't tested by pressurising then monitoring the pressure over a reasonable period, any leak will appear as a fall in pressure - wouldn't that 'just' require access to each end of a section and a suitable gas, say nitrogen, to fill it with? Wouldn't this be a more certain test than listening for leaks? It was noticeable during Gp Capt Hickman's grilling - and that does look to be adversarial to me, and I can quite understand how he might well have floundered a bit under attack - but his evidence citing the 'whistling sound' as a valid test amounted to groundcrew had done this and found leaks thereby - which is the worst kind of error in my book...all he knows from that is SOME leaks are found this way, he has no idea if dozens more are missed!
Oh, and I think Winco IS a pilot, it would be more convincing to point out flaws in his description of the leak testing than to continue this 'you aren't a pilot because you didn't answer fast enough ' bolleux...had he been trawling the internet for info he'd have had it posted within hours. Go for the ball* chaps, not the man.
Dave
*as opposed to the plural.
Winco,
With respect, as an independent engineer, your sniffer device IMHO is only useful where a small leak or weep is evident but because of the source cannot be readily identified due to a number of fuel connections close together, such as on a FCU on an engine. The sort of fuel leak that caused a fire 90 seconds after AAR would probably not have needed anything than a mark one eyeball should the aircraft have survived and landed successfully. Regarding a soapy water test being used for an air leak there is no harm in trying it but it all depends on the make up of the solution and the leak being a large one, I agree that small leaks may not cause any bubbles to form.
On another angle, I am sure we used FRS coupling seals on a RAF aircraft a long time ago, and I recall that I thought that if they were disturbed there could be a problem, to remind me could anyone produce a diagram on how the seals are supposed to work?
With respect, as an independent engineer, your sniffer device IMHO is only useful where a small leak or weep is evident but because of the source cannot be readily identified due to a number of fuel connections close together, such as on a FCU on an engine. The sort of fuel leak that caused a fire 90 seconds after AAR would probably not have needed anything than a mark one eyeball should the aircraft have survived and landed successfully. Regarding a soapy water test being used for an air leak there is no harm in trying it but it all depends on the make up of the solution and the leak being a large one, I agree that small leaks may not cause any bubbles to form.
On another angle, I am sure we used FRS coupling seals on a RAF aircraft a long time ago, and I recall that I thought that if they were disturbed there could be a problem, to remind me could anyone produce a diagram on how the seals are supposed to work?
Join Date: Apr 2006
Location: Back in Geordie Land
Posts: 492
Likes: 0
Received 0 Likes
on
0 Posts
Oldlae,
Thank you for that.
I am not trying to ridicule anyone here, not even Nimnrod AGE(its just a bit of fun banter) but I think that as there are better and more accurate and reliable methods of detection and location, it is of concern that the RAF does NOT appear to be using them. Instead, they are using the discredited method of soapy water.
I am simply seeking some clarification at to what WAS used and what IS used today. The lack of repsonce from the engineering 'experts' on this subject seems to say it all I think.
As an independant engineer, what would you use? Am I right in thinking that a small leak is likely to become a major leak with say an overpressurisation of the system, as occurs post AAR?
Thank you for that.
I am not trying to ridicule anyone here, not even Nimnrod AGE(its just a bit of fun banter) but I think that as there are better and more accurate and reliable methods of detection and location, it is of concern that the RAF does NOT appear to be using them. Instead, they are using the discredited method of soapy water.
I am simply seeking some clarification at to what WAS used and what IS used today. The lack of repsonce from the engineering 'experts' on this subject seems to say it all I think.
As an independant engineer, what would you use? Am I right in thinking that a small leak is likely to become a major leak with say an overpressurisation of the system, as occurs post AAR?
Winco
Ok, the soapy water thing is bugging me...
For gaseous leaks, we use a liquid called 'Snoop'. It is designed to bubble when used on a system that is leaking (ie a pressurised nitrogen system - the radar for instance...) What it is made of, I'm not sure, and in times of dificulty, where none is available, any liquid would probably do the job. It's simply that Snoop is designed for it and is a recognised engineering method.
For actual fuel leaks, as Oldlae says, the mark 1 eyeball is the best method. A leak will normally be detected because it becomes visible, ie the coupling is wet, or it has tracked it's way out of the area it is in, and made it's way on to the ground. This is usually the first sign of a leak - when there's a puddle on the ground or in a panel when opened. If we're looking at the seal because it's jsut been replaced, then full pressure is applied, and the coupling observed. Any leak will be visible within a short amount of time. If there is none, it is coated in an anti-corrosive coating and jobs-a-good-un.
Integral tanks like the wings are a differnt method. Again, usually first spotted by visually seeing the leak, other methods are used when leak mapping. A powder is placed along all the areas where leaking is likely to occur, and this will highlight any fuel it comes into contact with.
Ok, the soapy water thing is bugging me...
For gaseous leaks, we use a liquid called 'Snoop'. It is designed to bubble when used on a system that is leaking (ie a pressurised nitrogen system - the radar for instance...) What it is made of, I'm not sure, and in times of dificulty, where none is available, any liquid would probably do the job. It's simply that Snoop is designed for it and is a recognised engineering method.
For actual fuel leaks, as Oldlae says, the mark 1 eyeball is the best method. A leak will normally be detected because it becomes visible, ie the coupling is wet, or it has tracked it's way out of the area it is in, and made it's way on to the ground. This is usually the first sign of a leak - when there's a puddle on the ground or in a panel when opened. If we're looking at the seal because it's jsut been replaced, then full pressure is applied, and the coupling observed. Any leak will be visible within a short amount of time. If there is none, it is coated in an anti-corrosive coating and jobs-a-good-un.
Integral tanks like the wings are a differnt method. Again, usually first spotted by visually seeing the leak, other methods are used when leak mapping. A powder is placed along all the areas where leaking is likely to occur, and this will highlight any fuel it comes into contact with.
Join Date: Nov 2006
Location: Kinloss
Posts: 78
Likes: 0
Received 0 Likes
on
0 Posts
For god sake Winco.
I decline to comment on current methods because I cannot say whether new methods have been introduced since I left and now I am the walt? Things have moved at pace over at Kinloss so it would be wrong of me to comment but still you have a go.
Plenty of current Nimrod Air and Ground Crew on here will vouch for my identity and engineering integrity, can the same be said for you?
Many, many times I have been on Ops the success of those Ops have been down to my leadership of an engineering team in some very hostile and demanding circumstances where engineering decisions made by me (and the team) have resulted in our glorious flyers saving lives and getting bad guys.
On the reverse of that I have stopped aircraft that were unsafe from flying under some serious pressure from engineering officers who knew little about either engineering of the implications of fuel leaks on the Nimrod.
Stop making yourself look like a horses ass.
Oh by the way the approach speed for a B747 is 180 - 150 kts @ Flap2 (Kyb 2), yes I too can use a search engine but just because I can look it up doesn't make me a pilot does it.
I decline to comment on current methods because I cannot say whether new methods have been introduced since I left and now I am the walt? Things have moved at pace over at Kinloss so it would be wrong of me to comment but still you have a go.
Plenty of current Nimrod Air and Ground Crew on here will vouch for my identity and engineering integrity, can the same be said for you?
Many, many times I have been on Ops the success of those Ops have been down to my leadership of an engineering team in some very hostile and demanding circumstances where engineering decisions made by me (and the team) have resulted in our glorious flyers saving lives and getting bad guys.
On the reverse of that I have stopped aircraft that were unsafe from flying under some serious pressure from engineering officers who knew little about either engineering of the implications of fuel leaks on the Nimrod.
Stop making yourself look like a horses ass.
Oh by the way the approach speed for a B747 is 180 - 150 kts @ Flap2 (Kyb 2), yes I too can use a search engine but just because I can look it up doesn't make me a pilot does it.
Guest
Posts: n/a
I can vouch for Mightyhunter Ages professionalism , being quite fortunate to have spent some time in the sandpit him and he takes nae ****e fae anyone. That is something that many these days lack and having the balls to tell somebody many times higher rank the simple words... no
And the fact he knows me sister for long time I best say something nice
Going back to RAF Techies words of penetrant powder stuff on wing , bloody hell as sootie now I had the joy of doing that job one night and It took a very very long time spraying this white stuff on both wings upper and lower, of course the comedy C*** has to be done as well , but it sure does show seeps very well. Cannot be done of course in rib 1 area or bomb bay and the good old visual inspection or smell is only clues to a fuel leak , believe me if you have a leak you will see it , preferably done over a dry surface though. If there are other methods of doing these leaks then please tell me as I have not been taught them yet.
I like many now are all becoming multi trade and I can by law do sootie as well as airframe now including paperwork for these kind of jobs but I refuse to do it without somebody who is experienced to go through the AP and teach/show us how the system works , only when we all have had a few years experience on these things that we can be fully confident working them and of couse supervising. I get asked like many to do jobs courtesy of what I can do now but I like all the guys I work with if you dont know you refuse, winds the management up no end as they under pressure to get the jets up but this is the simple bare facts these days. The RAF let a few thousand experienced engineers leave and we really miss that now , same for all trades now. We are expected to do the same job with 1/4 of the manpower we had 5 years ago.
anyway Rant over , time to get pished !!
And the fact he knows me sister for long time I best say something nice
Going back to RAF Techies words of penetrant powder stuff on wing , bloody hell as sootie now I had the joy of doing that job one night and It took a very very long time spraying this white stuff on both wings upper and lower, of course the comedy C*** has to be done as well , but it sure does show seeps very well. Cannot be done of course in rib 1 area or bomb bay and the good old visual inspection or smell is only clues to a fuel leak , believe me if you have a leak you will see it , preferably done over a dry surface though. If there are other methods of doing these leaks then please tell me as I have not been taught them yet.
I like many now are all becoming multi trade and I can by law do sootie as well as airframe now including paperwork for these kind of jobs but I refuse to do it without somebody who is experienced to go through the AP and teach/show us how the system works , only when we all have had a few years experience on these things that we can be fully confident working them and of couse supervising. I get asked like many to do jobs courtesy of what I can do now but I like all the guys I work with if you dont know you refuse, winds the management up no end as they under pressure to get the jets up but this is the simple bare facts these days. The RAF let a few thousand experienced engineers leave and we really miss that now , same for all trades now. We are expected to do the same job with 1/4 of the manpower we had 5 years ago.
anyway Rant over , time to get pished !!
Last edited by KeepItTidy; 5th Jul 2008 at 19:43.
Join Date: Jul 2002
Location: UK Sometimes
Posts: 1,062
Likes: 0
Received 0 Likes
on
0 Posts
Help required
Now that MHAGE and Winco have stopped hitting eachother with their handbags (ya, boo, sucks), perhaps someone could point me in the direction of a reference regarding
"time to reduce to ALARP"
Essentially, I can't find anything in DS 00-56, JSP553 or R2P2 that says categorically 'an organisation has x amount of time to make the risks ALARP'.
This is a little strange, as otherwise the organisation could say ad infinitum
"Oh we've got a plan for that and we're working towards ALARP"
(does that sound familiar??)
The only thing that remotely refers to time, is a comment in R2P2 that infers that the risks should be assessed more than once in a year. Perhaps meaning 6 months to ALARP? If then if not ALARP, what happens next?
Any comment?
flipster
"time to reduce to ALARP"
Essentially, I can't find anything in DS 00-56, JSP553 or R2P2 that says categorically 'an organisation has x amount of time to make the risks ALARP'.
This is a little strange, as otherwise the organisation could say ad infinitum
"Oh we've got a plan for that and we're working towards ALARP"
(does that sound familiar??)
The only thing that remotely refers to time, is a comment in R2P2 that infers that the risks should be assessed more than once in a year. Perhaps meaning 6 months to ALARP? If then if not ALARP, what happens next?
Any comment?
flipster
Join Date: Mar 2006
Location: wilts
Posts: 1,667
Likes: 0
Received 0 Likes
on
0 Posts
Flip I understand that the families are meeting the Defence Minister and CDS in a few days time, hopefully Sir Jock will be able to provide a few answers, a few references and explain the ridiculous contradictions coming from the RAF and MoD in this case, specifically concerning ALARP and airworthiness. Nobody appears to be able to explain why Nimrod did not get fitted with dry bay protection since it was spec'd back in 1981. Nobody has explained why Nimrod did not get the same modifications as the VC10 fleet in the mid 1990's, concerning AAR. It would also be very useful to know if a safety review was carried out on the Nimrod fleet when it's change of use came about over land in Afg. A change of use, safety review is a requirement to meet airworthiness regulations. Overland Afg Ops might have thrown up a need for dry bay protection, bomb bay protection and fuel tank protection.
Nobody has explained why the six recommendations concerning AAR were ignored in the QQ report and why the decision was taken to stop AAR sorties only after the November incident. Nobody has explained how many of the 30 recs have been implemented to date and whether it is true that the majority of these recommendations will have been implemented by the end of the year. Nobody has explained why it is, that NOT having a current in date set of tech publications, does NOT impinge on the safety of Nimrod.
Nobody has explained why it is that MRA4 has LESS protection than the aircraft it replaces.
Namely,
No flight deck armour,
No under floor fire protection,
No bomb bay protection,
No fuel probe inerting system,
No dry bay protection,
No fuel tank protection.
Unlike the MMA P8A due to come into service at the same time.
Nobody has explained if any lessons have been learned here.
Could be a long meeting.
Nobody has explained why the six recommendations concerning AAR were ignored in the QQ report and why the decision was taken to stop AAR sorties only after the November incident. Nobody has explained how many of the 30 recs have been implemented to date and whether it is true that the majority of these recommendations will have been implemented by the end of the year. Nobody has explained why it is, that NOT having a current in date set of tech publications, does NOT impinge on the safety of Nimrod.
Nobody has explained why it is that MRA4 has LESS protection than the aircraft it replaces.
Namely,
No flight deck armour,
No under floor fire protection,
No bomb bay protection,
No fuel probe inerting system,
No dry bay protection,
No fuel tank protection.
Unlike the MMA P8A due to come into service at the same time.
Nobody has explained if any lessons have been learned here.
Could be a long meeting.
Last edited by nigegilb; 7th Jul 2008 at 11:00.