F111UPS767...
Has anyone any information on an aircraft fire where the crew descended to 25,000 unpressurized and what the results were? How about manufacturer or government testing regarding fire suppression at 25,000 pressure altitude?
Jet Jockey A4...
Regardless of altitude the percentage of oxygen in the air remains at 21%.
So depressurizing an aircraft at altitude will have no effect on snuffing out a fire.
A fire will sustain itself with an oxygen content down to 16%.
JJ - I did a bit of searching and came up with "mass burning rate" and have found studies that show that mbr is lower at low ambient pressure at high altitude. However, I cannot find a good answer yet to the original question, above.