The F-22 has been grounded now since May and I don't read of any solution to the problem...
"There is a lot of nasty stuff getting pumped into the pilots’ bloodstream through what they’re breathing from that OBOGS [On-Board Oxygen Generation System]. That’s fact,” one former F-22 pilot told Dave Majumdar of the Air Force Times a few weeks ago. “How bad it is, what type it is, exactly how much of it, how long -- all these things have not been answered.”
Whatever it is the pilots are breathing has been causing hypoxia -- a lack of oxygen that can lead to reduced brain function, memory loss, and cognitive problems. On top of that, anti-freeze, propane, and synthetic motor oil have recently been found in F-22 pilots' bloodstreams."
question where is this nasty stuff coming from.?.. I will hazard a quess that this oxygen system is is chemically different than the canisters on commercial a/c.
Awhile ago there were people saying scrap the F-35 .. make more F-22s... it now appears that both have problems.