Any here actually KNOW if you could put effective fire supressant technology into a hugh drafty space like the nimrod bomb bay and what it would take? Intuitively it sounds totally impractical to me, though it would be interesting to know how it could be done (if at all).
It seems that there are a few here who think they know. When the jet was designed, extinguishers were fitted (routed) into the engine bays, the underfloor bays and the crew compartment (for direction by hand into the avionics crates). That is sufficent evidence to me that fire protection was extensively considered. I don't think the Comet had underfloor extinguishers, but I stand to be corrected. There is no record, but I would guess that fire extinguishant for the bomb bay was discussed by people who did know about quantities and effects. The design was for fuel tanks to go in the bay for extended range, but they were never (I believe) fitted. As I mentioned in my first post, the tanks would have taken up sufficient volume in the bay to facilitate use of extinguishant around them, just like the engines do in their own compartments. So, fire bottles were planned to go in there only if the tanks were fitted.
Just to add to my comments about the ability of the bay to leak vast amounts of air air with the doors shut, approx one third of the cabin pressurization air is exhausted into the bay as well, and it still will not pressurize.
I'm convinced that it cannot be done with an empty bay, even with modern gasses, but thats only my opinion. I'm content and have nothing to prove because I have no argument against the status quo. Those who want to challenge the status quo should contact Graviner and get some qualified information. Otherwise I believe we will simply go around in circles.
The MRA4 has 2 independant bomb bays, so the problem is more than halved. Again, it would only be a guess as to how much extinguishant would be needed. I hope it can be achieved and, if so, I hope it will be given consideration.