Entire OT, but ..... I found this answer under an AW&ST article:
on Jul 31, 2017
I had the privilege of litigating Capt. Haney's accident. It was appalling to see how the Air Force, so intent on covering its incompetent asses, blamed him for this accident. Lockheed was given an additional 25 million dollars to study the problem after the accident and the F-22s were grounded because so many pilots reported breathing issues, a problem that it and Boeing were to have solved when they signed on to build this aircraft and before they took 100 million each to field them.
Since the OBOGS issue affects so much of our fleet I suggest we buy a new SU-35 and learn two things. How to make an aircraft that runs circles around anything we have and how to build one that has one enemy and it isn't the aircraft itself!