"Military-style" masks? I think you will find that there is quite a difference between the O2 equipment used in strike aircraft compared to the 'quick-don' masks used in airliners. There are variations within the services -- example, the USAF, RAF and RAAF used diluter demand masks that vary the proportion of O2 delivered depending on altitude. The US Naval air services and USMC use 100% O2 only due to risk that such can supply oxygen if the pilot finds himself underwater (catapult problem, anyone?)
The flight crew masks that are fitted to airliners are designed for airliner use, and most would be of the quick-don, diluter demand type, with the ability to deliver O2 under pressure.
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The environmental risks of unpressurised flight above FL140 (and above FL250 in particular) far outweigh the risk of discomfort and barotrauma.
Above FL140 the occupants will suffer hypoxia.
Additionally, above FL250 the dissolved gases in your body will start to come out of solution and occupants may suffer decompression symptoms and injuries.
Emergency descents are designed to get the aircraft's occupants out of these danger zones as quickly as possible.
Emergency descent flight profiles are therefore designed to achieve the highest rate of descent possible. Mmo/Vmo, idle thrust, clean, spoilers/airbrakes deployed. One type I flew recommended a moderate angle of bank to increase the RoD. More recent types only specify a turn as a traffic avoidance manouevre only, should that be desireable.
If airframe damage is suspected, airspeed is reduced from Mmo/Vmo to a lower speed, maybe Va or
Vb. Once again, a risk management approach -- less likely to tear bits of airframe away that might otherwise be useful, at the cost of slightly longer exposure of your crew/pax to the hostile environment.
Passenger "discomfort" and barotrauma rate very low in comparison to these other risks.
Passenger reactions to emergency descent range from seat gripping fear, to annoyance at not reaching their desired destination. G-force during the manouvres are not noticeably greater or less than normally experienced by the travelling public, deck angles and bank angles may be unusual for a frequent traveller but not extreme.
See if I can find a useful reference for you....