Gents, a few points if I may.
The AAr system as currently installed on the MR Mk2P Nimrod (MRA2, if you wish!) is radically different to the original "falklands lash-up" of the early '80s.
The main feed is now a single pipe running from the rear end of the probe down through the pressure shell, going under the floor at the port rear of the cockpit and then through the pressure shell again into the bomb-bay, quite far forward.
This in itself is a vast safety improvement (risk mimimisation, regardless of whether any incidents had occurred or not) on the early twin rubber hoses that snaked their way down the inside of the crew compartment, constantly getting walked on etc.
This single-skinned but thick-walled pipe (metal, not rubber) now runs rearwards down the port side of the bomb-bay before splitting into two and going out into the rib 1 area at the front of the wings. From there, it basically runs rearwards down either rib 1 until it connects to the main refuel gallery. This has eliminated the "lash-up" that utilised some of the 7-tank pipework and valves as AAR valves, considerably shortened the length of fuel pipework (hoses and metal) involved (especially within the crew compartment) and minimised the ammount of fuel pipework routed near "hot zones".
Now, this had to be done for good reason, for the bean-counters to allow such spending for what is a relatively radical and comprehensive re-design, so for anyone who wishes to simply claim that no-one pays heed to safety until it all goes wrong, here is proof that someone did indeed think, before something possibly went wrong. It is with great sadness, however, that something did indeed go wrong, cause as yet unproven.
Unfortunately, this re-design hasn't been without some issues. Pipelines fretting against the AAR pipe and coupling leaks to name but 2. Now, with the best will in the world, and the utmost care and attention by the technicians carrying out these modifications to ensure correct routing and clearances, nothing can take into account the constant flexing of the airframe (if it didn't it'd snap!) and movement due to thermal expansion/contraction causing all the pipework to "settle" into the position that
it wants to adopt. That is what causes the fretting/leaks. Maybe there should have still been some hose sections to allow movement? I don't know, as I'm not a designer. I do know, however, that I wouldn't have attached a fuel pipe support bracket to a hot temp control valve.......
There are currently so few Nimrods flying, partly due to the rigorous checks and inspections being carried out to hopefully prevent any further catastrophe and unnecessary loss of life, the groundcrew do care and have a personal pride in their own workmanship, (at least, all the ones I personally know do) contrary to some popular beliefs. It seems to me that a lot of emphasis is being placed on AAR, now although this may well have been a possible leak source, there had to be an ignition source as well......