MRA4 AAR system
Betty, I stand by the following statement about MRA4 AAR. It has been the subject of a Parliamentary question and what I am claiming has not been denied by the MoD. There are some unpalatable truths about this tragedy and not everyone is comfortable dealing with them. I understand your concerns, but there is a very real chance that this could happen again. I have been told that the MRA4 design was frozen at the back end of last year, there is no OBIGGS or Foam on order and the AAR system is not double skinned, unlike the Tri Star. It is not being built to a Civil Standard, and the "fag packet" Falklands design is being adhered to.
The AAR system on MRA4 is the retained MR2 system. That means what the MR2 has, MRA4 will have also. That said, there are some differences, mainly where that fuel enters tanks in the Bomb Bay.
The AAR system will not be qualified on delivery. It has to be available ready to use at short notice.
The system does carry fuel though, and it is pressurised (& yes there have been leaks during ground refuel).
There is a requirement to 'design out' of MRA4 any known MR2 issues. To that end engineers are on the distribution for all Incident signals, Mods, STI, SI, RTI & UTI. Every one is looked at to see if it's applicable to MRA4. Where the MRA4 has the same parts ('retained') the issues are to be designed out.
There is no design for foam in tanks (neither Flight Deck Armour funnily enough). It will only go on MRA4 at the request of the customer.