Nige, I believe we met a number of years ago when we were both stuck in Azi; I respect what you have acheived wrt protection on the Herc and, indeed, what you are now trying to achive with the Nimrod. However, a word of caution now that you are dealing with an aircraft which is not your background (no offence intended at all). Be careful what you post as you can easily lead people astray.
In an earlier post (1464) you state that:
"Furthermore, BAe suggested that MR2 should fly with extended range tanks with fuel extinguishant. I am not particularly clever, but even I can work out that at a stroke this would negate the need for AAR and would provide fire protection at the same time."
This theme has now been picked up by others, but is incorrect. The AAR capability rendered the long range tanks obsolete, but it does not work the otherway round; long range tanks would not negate the need for AAR. You can take-on significatly more fuel through AAR (replenishing now empty tanks) than you can lift off the ground with long range tanks, due to the maximum take-off limitations of the aircraft. Without going into actual figures, if you filled all the fuselage and wing tanks on an MR2, you will be at (or just below) the design maximum take off weight. If long range tanks were available and could be fitted, you would only be able to increase the fuel load up to the overload maximum take-off weight. Not only would this reduce safety margins (especially in the hot climates) and increase fatigue, but it would only increase the endurance of the aircraft by about an hour.
TVM