Nimrod Information

[nigegilb]

WNM, thank you for clearing that up. The broader point here is that some people think we should all stay silent until the BoI is published, other people think differently. Here is a link to the Lynx that was shot down in Iraq.

http://www.mod.uk/DefenceInternet/Ab...ardsOfInquiry/

Check out the main recommendations. Huge chunks redacted. I happen to know a little bit about this tragedy, specifically about what happened on the ground. It has all been removed. This stuff is not secret, it is not useful to the enemy, it has simply been deleted.

I only hope that when the BoI for the Nimrod crash is published, it is published in full. If the MoD would make that promise now, I would happily stay silent.

BTW 50% of US combat losses in the Vietnam war were as a result of fuel tank explosions. Every operational aircraft and helo in the US inventory has fuel tank protection fitted as standard. My own sources have told me that Nimrod XV230 was brought down by a fuel tank explosion. Even if they are wrong, it does not excuse the MOD from sending crews to war without fuel tank protection. So no, Foam and Inert Gas is not the answer to everything, only about half of everything.

[Tappers Dad]

This is a typical BOI report as Nig says; Lynx BOI extract

1.  
   1. CONTRIBUTORY CAUSES 75. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX:
   2. a. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXX
   3. b. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
   4. c. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXX

If our BOI report is the same what justice or closure will we be getting .

[WasNaeMe]

DV

Correct, in that...

• If the MR2 design which is retained is flawed, obviously MRA4 will be similarly flawed. But nothing so far has been proven to be flawed.
• The AAR system is not double skinned.
• The qual of the AAR system will be for the customer to define.

The finger has been pointed at the AAR system and speculation (rumour) has it that this may have caused the tragic events in Afghanistan. A BOI has been set up to report on the circumstances which led to the tragedy & make recommendations such that the same events do not lead to another.
Lets wait until the report hits the streets, then we can offer up our expert opinions. It may not be the AAR system. It may be undetermined...... Lets wait a little longer.

[toddbabe]

what do you mean maybe undetermined?

[Tappers Dad]

Steve Austin said

Short Fat One (who is not a ISK by the way) and Betty Swallox are both involved in the MRA4 programme, have a working knowledge of the MRA4 systems, have flown the aircraft, are current to fly the aircraft, and, therefore, know more about the aircraft, its systems and the safety case than most people on this thread.

Ok ,so here is a question for The Short Fat One and Betty Swallox

Given the fact there have now been 2 bomb bay fires on Nimrods will the Safety Case reflect this and recommend fitting some form of fire fighting exuipment in the Bomb Bay . Or does the Safety Case for the MRA4 start by saying well there has been no incidents with this a/c therefore it is safe??

[WasNaeMe]

Toddbabe
It may have been this, It may have been that..... Conjecture. It may be that the cause cannot be positively identified....

With very little access to the wreckage (as reported somewhere..) it must be a nightmare trying to establish the cause.

I have no insider knowledge before anyone jumps on that bandwagon.

[Safeware]

TD,

Probably neither,

The safety case should reflect the level of risk. There may well be a risk of loss of aircraft through fire. The safety case should should identify the hazards leading to such an accident and show that such hazards have been mitigated to an acceptable level (As Low As Reasonably Practical). Such an level doesn't mean no risk though. The problem though, is for those risks which are not Intolerable, but also not Broadly Acceptable. There will always be debate over such Tolerable risks because of all the factors and stakeholders views that a duty holder is trying to balance when deciding whether to accept such a risk.

sw

[nigegilb]

There are aspects of the Lynx crash that are extremely unpalatable. But is this really the right way to deal with it?

THE DAS FIT 30. Background. The 847 NAS Lynx Mk 7s were originally fitted with a XXXXX flare system using stock held by the Lynx IPT from a legacy Service Modification. This was to satisfy an unfunded requirement to fit Lynx with DAS. More recently funding was released to fit a further 15 Hamden Lynx Mk 7 with a DAS fit. XXXXX was invited to deliver a further tranche of XXXXX, however it was no longer in production. The XXXXX chaff and flare system was offered as an alternative and due to its similarity with the XXXXX system, the Lynx IPT selected it to simplify the modification process. There was also an aspiration to upgrade the XXXXX to the XXXXX system in order to achieve fleet commonality and to improve supportability. This aspiration was eventually realised and XXXXX was introduced under a Service Deviation approved by the Release to Service Authority, HQ DAAvn (Reference O). The 847 NAS Lynx had the modification carried out in theatre by a Service mods team from 7 Bn REME. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
31. Advice on DAS Effectiveness. The opinion of the AWC is that the Lynx has one of the most effective DAS suites of all the UK helicopter assets in theatre. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
34. XXXXXXXXXXXXXXXXXXXXXXXXXX. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX: a. XXXXXXXXXXXXXXXXXX. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Page 15 of 34
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
b. XXXXXXXXXXXXXXXXXXXXXXXXXXX. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX c. XXXXXXXXX. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
d. XXXXXXXXXXXXX. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX. e. XXXXXXXXXXXXXX. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X
XXXXXXX XXXXXXXXXXXXXXXXXXXXX
f. XXXXXX. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX.
5. XXXXXXXXXXXXXXX. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXX

[Winco]

Safeware

Your comments concern me slightly.

You say that the risks should be 'mitigated to an acceptable level (As Low As Reasonably Practical)' Might I ask you what exactly constitutes an acceptable level? My own view is that if there exists a risk with an aircraft, then that aircraft should not be flown and should certainly not enter service. The Secretary of State for Defence has a 'duty of care' responsibility to all military personel, as does the RAF hierarchy to RAF personel. If there is any doubt as to the safety of the aircraft, then there should be no doubt about it not being flown IMHO.

You see, from reading this thread and the others, there has clearly been a serious fuel leak problem with the Nimrod aircraft over the past few years and a problem in general with the fuel system for a lot longer. I am slightly confused by what has been said by Nigel, Betty and the Short One. It certainly appears that they are at odds with each other about the fuel system and if, as you say, they are all on the project, why are there such discrepancies?

I am also concerned that as Nimrod 4 is being hailed 'a new-build' aircraft, that things such as foam, inert gases in the bomb bay etc are not being incorporated now into what is alledgedly a new aircraft? Why has that been overlooked? Did no one learn any lessons from the loss of the Hercules? Surely they did?

Mr Austin, whilst TSM might be generalising a little, I think it would be fair to say that we have heard 3 stories, from 3 different 'MR4' people, about the very same fuel system, and all three are somewhat different. Could you explain to me why that is please? I am not being rude, but I genuingly don't understand why there are differences.

Thank you.
The Winco

[Safeware]

Winco, I fully understand the issues of duty of care - I'm not trying to defend or justify the safety argument being used on Nimrod, merely to explain 'the facts of life' in relation to risk management.

Absolutely safe aircraft are ones that don't fly. In HSE terms, a Broadly Acceptable level of risk for an activity is one where the per annum risk of death to an individual is 1 in a million. An Intolerable level of risk is generally accepted as 1 in 1000. In between is the Tolerable region, where the benefit gained must be balanced against the level of risk.

In coarse terms, one of the riskiest things people do is drive a car. However, society accepts the level of risk because of the benefits having a car brings. Flying has its risks, and a duty holder has to balance the level of riisk with the benefit gained. While not getting into an argument of the rights and wrongs and levels of risk, this is what the duty holder for Nimrod will have had to consider when authorising AAR post the XV230 incident - is the level of risk in conducting AAR worth it for the beneifit it brings?

Trust me, I'm not known for buying into cr@p safety arguments.


sw

[betty swallox]

Nigegilb. Apologies if I misconstrued what you were saying; I retract my statement "fundamentally wrong".
For the record, I am in agreement with ShortFatOne; we do "sing off the same sheet, etc".

Tappers Dad. We haven't communicated before. I am genuinely sorry for your loss. I didn't know Ben, but I was close to all the ex-206 guys. Unfortunately I am unqualified and not in a position to reply to your question, much as I would like to.

Regards,
BS

[toddbabe]

Wasnaeme Sorry I was taking the piss I don't think for one minute that the board of enquiry will be able to determine very much at all for the very same reasons that you stated.

[nigegilb]

BS, no worries, I am just concerned that the redactors are getting more heavy handed as the BoIs appear.

Take this line from the Lynx BoI;

Advice on DAS Effectiveness. The opinion of the AWC is that the Lynx has one of the most effective DAS suites of all the UK helicopter assets in theatre.

OK, so how come this particular Lynx was shot down then?

Notice that AWC refer to "the Lynx," in general and does not refer to the Lynx that was shot down. The type of missile is a point of interest here, but I know there were other factors that affected this particular flight. Once again, it will fall on the Coroner to decide what information can be placed in the public arena. The BoI has a limited usefulness. Problem with the Inquest is the lengthy time frame. I hope you can understand what TD is trying to do.

[Winco]

Safeware
Thank you for your explanation, and whilst I don't accept the bit about absolutely safe aircraft not flying, I do understand where you are coming from. But I still have concerns over this fuel system 'problem' that we seem to all keep coming back to.

Whatever the statistics are, there does seem to be common ground in the understanding that Nimrod 2 has a fuel system problem. Now that may well be down to age of components etc. however, it appears that the MR4 is NOT being manufactured to a better degree of safety (Fuel system wise) than the MR2 currently is. The IFR system on the MR2 was fitted in weeks - literally. I know, because I was at kinloss when the likes of John R, Martin C (and others) trialed it prior to going South. It was an 'emergency fix' to get us to the south Atlantic, and as such we all accepted it as so. But from what I can glean from others still on the fleet, nothing much has changed, other than the pipes no longer trail through the cabin prior to going into the tanks.

Now the system at the time was a success, no question about it, but was it the safest it could have been? I doubt it frankly. We often had fumes in the cabin post AAR, but we accepted it because it was an emergency 'short-term' fix and the success of the task out-weighed the possible dangers.

We are now some 25 years on, and it is proposed that we use exactly the same system in MR4, and in some cases the same components! Are you seriously suggesting that after 25 years, this 'ad-hoc, quick-fix' modification cannot be improved upon? I am sure it can, and I'm sure it can be made safer, but it all boils down to £££££££££££

The loss of the Hercules should have been a wake up call to CAS, ACAS, AOCs etc about the need for foam and inert gasses for fire suppression, especially on aircraft that have no escape systems. The loss of the Nimrod only highlights the fact that nothing was done as a result of the Hercules loss, and the powers on high should be ashamed of that.

The time has surely come when we must stop accepting a 'half safe' aircraft when, for the sake af some extra funding, we can make them (in your words) aircraft with a tolerable risk. I would suggest to you that at the moment, the risks are intolerable, NOT because we have only lost one Nimrod (one Nimrod too many of course) but because that risk can be greatly reduced, if not elliminated, by simply spending some money on retrofitting of inert gas, foam etc etc. Heavens above, Nimrod 2 dosn't even have a bomb bay fire extinguisher! Does the MR4 I wonder??

The Winco

[Roland Pulfrew]

OK, so how come this particular Lynx was shot down then?

Because despite having one of the best, the best wasn't good enough!!!!

[AC Ovee]

But from what I can glean from others still on the fleet, nothing much has changed, other than the pipes no longer trail through the cabin prior to going into the tanks.

Now the system at the time was a success, no question about it, but was it the safest it could have been? I doubt it frankly. We often had fumes in the cabin post AAR, but we accepted it because it was an emergency 'short-term' fix and the success of the task out-weighed the possible dangers.

Winco, the originally designed refuel system (no AAR pipes) in the 1970s, has not changed, but has been regularly removed, inspected and re-fitted. The initial probe and temporory pipework that was put together during the Falklands War has long since gone. The new AAR pipework, that by necessity has to pass through the cabin, is double skinned and is monitored for interspace leaks by a detector. We have definitely moved on from the initial AAR mod.

[AC Ovee]

Heavens above, Nimrod 2 dosn't even have a bomb bay fire extinguisher! Does the MR4 I wonder??

The Nimrod Mr2 bomb bay is huge. When it has fuel tanks in it, taking up a lot space, the volume available outside the tanks to inject extinguishant into, to suppress fire is a great deal smaller, so fire extinguishers were a practical precaution.

I would guess that the size of extinguisher bottle(s), with pre-positioned spray heads/tubes needed to put out a fire in an empty Nimrod bomb bay would probably take up at least a third of the space in the bay. It would need a sustained blast of extinguishant throughout the bay. Is that practical? No.

[Tappers Dad]

AC Ovee
Is that practical ?


Air Safety Week, April 19, 1999
Inert gas generators
According to Bill Leach, fire protection team leader for the Naval Air System Command, an inert gas generating system has been developed with potential application to commercial airliners. "An air bag without the bag is effectively what we have," he said. When an air bag is activated, the chemical reaction produces a large volume of nitrogen gas almost instantaneously.
Metal canisters, filled with the same chemicals, with holes predrilled to exhaust the gas and with electrically-activated initiators, have been placed in the dry bays of Navy F-18 fighter-bombers and V-22 tilt-rotor aircraft to provide near-instant fire protection.
In the dry bay forward of the engines on the F-18, for example, six generators, two optical sensors and a "smart control box" provide fire protection with a two millisecond reaction time. Since the generators produce a great deal of inert gas very quickly, they are activated in a carefully-timed sequence to corral fires while avoiding overpressures that would distort the aircraft structure.
A similar system installed in the mid- and trailing area of the wing is credited with saving a V-22 which recently experienced a hydraulic fire.
The technology, Leach believes, can be exploited to deal with the polyimide fire threat in commercial aircraft. "We have taken the concept from the commercial automobile industry, applied it to military aircraft, and we have an opportunity to go full circle back to commercial aircraft," Leach said. The added weight is marginal. "You can almost describe this system as prepositioned fire extinguishers," since bottles and lines are avoided, Leach added.

http://findarticles.com/p/articles/m...13/ai_54428998

[nigegilb]

I don't know how the size of the Nimrod bomb bay compares with aft and fwd cargo bays on a 747 400 but I do know there is considerable fire protection on a Boeing. MR2 is a make do aircraft, in these Nimrod plus roles. But really, the MRA4 is supposed to be a brand new aircraft there is no excuse for it not to have the latest levels of protection. FFS the P3 had fuel tank protection 30 years ago. Are we really going to bring in another generation of Nimrod ac without adequate fire and fuel tank protection?

[Len Ganley]

Nigegilb.

I can answer that first question for you. Please check your PMs