A few pilots have told the Air Force they won't fly their expensive F-22 Raptor stealth jets because no cause has been found for oxygen deprivation incidents in the cockpit, the head of Air Combat Command for the U.S. Air Force told reporters.
The Air Force has been looking for the cause of about a dozen unexplained incidents related to hypoxia, or oxygen deficiency, with pilots, but so far has been unable to pinpoint it, Gen. Mike Hostage with Air Combat Command said in a media briefing.
Hostage noted it was a very small group of pilots who opposed flying the Raptors. Pilots began experiencing problems starting four years ago.
“For some reason, the on-board oxygen generating system and the environmental control system that feeds it may be inputting some contaminant,” Gen. Gregory Martin, a retired Air Force veteran, told CNN affiliate WAVY in Virginia.
Hostage said if a contaminant is not the problem, there may be something else hindering pilots from getting enough oxygen.
Hostage spoke at length with reporters about the issue, which has plagued the fleet since problems with the F-22’s oxygen supply system were first reported in 2008. The jets have previously been grounded to examine the issue , but one year ago the Raptors were again cleared and allowed to fly. In January 2011, the jets were limited to altitudes under 25,000 feet during an ongoing investigation into a November 2010 crash. Flying above that altitude could cause a pilot to black out from lack of oxygen and lose control.
"We are diligently pursuing a variety of hypotheses to try and understand and characterize the exact circumstances we've been experiencing," he said.
The Air Combat Command said it still has not identified the "root cause" of the oxygen issue, but is making progress with its investigation and hopes to soon determine the exact cause of the problem.
“The smoking gun is disassembled in a mosaic in front of us. ... At some point we’re going to have the smoking gun assembled,” Maj. Gen. Charles Lyon, the director of operations for ACC, told the Air Force Times.
While Hostage said that there was certainly a concern about the group of incidents, he didn't think it was necessary to pull the entire group of jets, which have had 12,000 deployments and a total of 15,000 flight hours since September 11 and only a handful of problems. The Air Force has also made sure to add new emergency oxygen deployment handles, should a pilot encounter any issues.
And the F-22s are still being used when needed, including a recent deployment by the Air Force of a squadron of the Raptors to southwest Asia.
"I fully expect we'll get to a solution," Hostage said. "I won't give you a timetable, but we have made great progress to that effect and am confident we'll put this behind, we'll be able to explain it, and we'll retool the airplane to make this problem go away."
Read more on the F-22's oxygen problems:
Air Force's F-22 back in service after 4-month grounding
Air Force grounds F-22s over oxygen system concerns
I guess those pilots picked a bad day to quit sniffing glue.
Now there's a solution. Don't go above 25,000 feet? That's kind of like the wheels on your car will fall off if you go above 70mph so just keep it slow.
Wow, nobody blamed this on Obama yet. Any moment now, here it comes.
Why? Obama would just in turn blame it on Bush.
Dont worry Obama will blame it on BUSH, it did start in 08
The YF-23 should've been chosen over the YF-22.
Not nearly pretty enough
These engineers that designed this plane just said that instead of the Alaska Pipeline having to be built they would just run a pipe to your but.
@duh- IGNORANCE IS BLISS.
cool, at least warren buffet wont make billions off his train company transporting oil from canada to oklahoma while his but bud obama says its all about the aquifer which is a lie because that already has millions of miles of pipeline in it and the keystone would be even safer because it'll be encased in cement.
The problem is that we had to cut corners to make the jet affordable. The same system that enriches the engine intake is used for purifying the pilots air. This is an existing part used in many aircraft. Because this jet flies much higher and faster than previous model, the valves used to separate engine air and pilot air are under much higher stress and some leaking is occuring. The correct way to fix this is to design new valves, which is impossible due to funding pressure.
Each unit costs half a billion dollars each. Cost cutting?
We had a similar bleed air problem in the Viper. So, you may be on to something.
The engineers that designed this plane just said that instead of the Alaska Pipeline having to be built they would just run a pipe to your but.
Why hasn't anyone put an f-22 into one of NASA's large vacuum chambers and depressurized (slightly, not to full vacuum but to equal pressure at 25,000 feet and up) and studied the O2 system? Did they study the specific aircraft involved in the reported hypoxia incidents?
You'd need to run the engines to test the problem. Can't to that in the enclosed space. But if you need data the system can be instrumented and flown.
Because a vacuum chamber is not the same operating environment as actual flight. That would be like putting an SUV on a dynamometer to check for rollover tendencies.
The engines need to be at full power to properly test this issue, which was tested in flight trials. However, because pilots are automatically grounded for 6 months if they report signs of apoxia, no test pilots came forward to report the issue. They were worried it was a problem with their ability to handle the stress of the new jet rather than a problem with the jet itself.
There was a time when the US could get a new fighter from prototype to squadron in about 5 years. I would use both the F-15 and F-16 as examples, both of which were the most advanced fighters in the world when they entered service. Now with the F-22 and F35 programs, it's now taking decades to go from prototype to front line service. The F-22 program began in 1986 with the first flight of the YF-22 in 1990 and the F-35 program began in 1996 with the first flight of the X-35 in 2001.
There was a time when aircraft manufacturers could put a completely new, unproven design in the air in less than 120 days, WITHOUT computers! P-51/A-36 by North American Aviation in WWII.
just tell the pilot to open the windows. Problem solved
I know one of the F-22 pilots that was affected by this. He and another pilot encountered hypoxia issues just minutes into a flight. Both wearing oximeters, one registered low levels, the other one did not. However, both had symptoms and one bad enough to warrant decompression chamber. AF racked it up to "physiological incidents" and pulled planes just for a weekend and the put them right back in the air.
My dad served 20 in the Army as a pilot and always said "Nothing is too good for our boys in service....and that is exactly what they get...nothing". It is high time they find and fix the problem and stop putting lives at risk. Not just the pilots, but those of us on the ground that live around the bases.
The problem is they put these planes (and other military hardware) into service before their development is anywhere near complete. Then they spend millions to billions of dollars trying to fix things that would not have been an issue if they would have taken the time to develop them, and get most of the bugs, out before deploying them. Not every bug can be fixed before a product goes into production, but the military (DoD) is notorious for large numbers of problems with their "latest technology".
I'll pay 2 cents on the dollar for one of these bad boys, then have a buddy of mine fix 'er up.
With the speed of todays technology one could spend a lifetime in developement. At some point design has to be frozen to get the package airborn and into production. Developement never stops all the way until the airframe has no more to offer. The more complicated the machine the more complicated the issues.
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