Skip to comments.F-22 redesign considered as oxygen system concerns linger
Posted on 03/02/2012 12:25:39 AM PST by U-238
US Air Force leaders are considering a redesign of the Lockheed Martin F-22 but still have no answers for the oxygen system breakdowns responsible for another operational disruption.
F-22s based in Alaska were grounded for one day in mid-February after three separate pilots reported hypoxia symptoms, the Air Combat Command confirmed to Flightglobal.
It was at least the third temporary stand-down for the F-22 since the USAF deactivated the entire fleet for four months until last September.
But air force officials are no closer to identifying the cause of the string of incidents, including one fatal crash in November 2010 that was preceded by a failure of the pilot's oxygen supply.
USAF officials hoped an expert panel led by retired Gen Gregory Martin might yield the answer. The team has now reported its findings, but found no "smoking gun", said Lt Gen Herbert Carlisle, deputy chief of staff for operations, plans and requirements.
The USAF is considering a broad range of options, including redesigning the F-22 to include a back-up oxygen supply, Carlisle said. This would automatically detect an oxygen system malfunction and activate, he added.
(Excerpt) Read more at flightglobal.com ...
Sounds like something external affected the separate aircraft on that day, rather than there being something internally wrong.
I thought funding for the F-22 was terminated. Now redesign?
Redesigning current aircraft happens.
The USAF will probably get the funding for it too.
There no indication of that the F-22 will go back into production.
Perhaps ‘modification’ (mod) is needed. ‘Redesign’ indicates that since they don’t know, they’ll redesign the entire system. But what if it’s not the oxygen system but phenomenon or other system having a negative impact on the oxygen system?
Wonder if the tubing intended to feed extra oxygen into the cockpit was freezing up and clogging. Also, there ought to be an oxygen level sensor in the cockpit — by the time subjective symptoms begin it may be too late to fix the problem.
All very good points
One thing I learned in the service,is that comfort really is everything when appropriate.I am going to assume that flying a jet is never gonna be easy but the pilot ought to be able to feel at home in his environment,not suffocating.
If each aircraft was experiencing similar flight characteristics and flight stresses, it seems the symptoms could be similar without there being a common external influence.
Some sort of flight characteristics seems to be causing the failure. They obviously have good supply for the most part, then something happens.
Something in the oxygen flow system design seems out of kilter. Sounds like they need to do an inch by inch test of the oxygen flow from the source to the pilot. Then push the system hard under similar circumstances to past failures. Something should pop up.
Now I know where they’re getting the non afterburner mach 2 cruise speeds. They divert the oxygen supply in to the fuel mixture. LOL Okay, I’ll shut up now.
I’m going to back your play on that sans-suffocating comment.
You either fix it or you junk it. Another screw up that will cost the tax payers millions.
“Wonder if the tubing intended to feed extra oxygen into the cockpit was freezing up and clogging.”
My thought was the tube was being compressed by the G’s. When the G’s flattened out, the tube expanded. You wouldn’t be able to detect it because there would be no evidence.
Give it to an 8 year old to solve. Probably something so simple the geeks would never think about it.
Perhaps not even the G’s on the tube itself (no need for it to be flexible as a wet noodle) but on apparatus attached to it.