LO, the type of OBIGGS earmarked for A400M is the latest generation constant breathing gas generating system. This protection is much lighter and easier to use than the gen1 nitrogen sytems. Hence the reason for this kind of protection now being fitted as standard to civil airliners. The shere weight and bulkiness had precluded its use until recently. For P3 Orion, USN went for foam. Lightweight, with a small loss of fuel tank capacity and very little maintenance. Foam was also chosen for C130J in a more recent study. Very latest Hercs have switched to latest generation OBIGGS.
Point is they always have some kind of fuel tank protection.
A400M replaces C130K like for like, same role, same job. The case for fuel tank protection has already been made for C130K; it does not need to be made yet again. This stinks of saving money when a safety case has already been made after the loss of an aircraft and crew.
Different in the case of the MRA4. A counter argument to fitting protection to Nimrod might be, in the case of XV230, the amount of aluminium burning negating the explosive protection offered by foam/OBIGGS. I am unconvinced by this argument. XV230 was very close to Kandahar, just as
XV179 was minutes from the safety of a concrete runway. Besides, more fire protection might have prevented a catastrophic fire from developing. There is absolutely no sign of improved fire protection in MRA4, in fact, it has less fire protection than the ac it replaces.
I am at a complete loss to understand why MRA4 has been stripped of it's AAR probe inerting system. I can only figure it is due to financial pressure. The probe will be charged with fuel, regardless of any requirement for AAR capability.
Obviously we have to wait for the BoI. With regard to Flight Deck Armour, if you could guarantee never having to land/take off in vicinity of hostiles, sure, leave it behind, but we live in the real world.
Last edited by nigegilb; 16th Oct 2007 at 17:50.