Air Force places F-22 blame on valve

Air Force Maj. Gen. Charles Lyon, the director of operations for Air Combat Command, told the Pentagon press corps Tuesday the service never found its “smoking gun” in its search to figure out what was causing hypoxia-like symptoms when flying the F-22. Throughout the presentation, though, he placed blame squarely on a valve that inflates the Combat Edge upper pressure garment.

He listed connectors and hoses in the cockpit during the press conference. However, it’s the valve that is getting replaced. Testing on the valve is also the update Defense Secretary Leon Panetta wants to receive before lifting altitude restrictions on the stealth fighter fleet.

This valve on the Combat Edge vest is not unique to the F-22. F-15 and F-16 pilots wore them from 1992 until 2004 when service officials told them to stop “because they were not giving us the contribution we thought they would.” F-22 pilots kept wearing the vests because of the increased altitudes the F-22 can fly.

Lyon explained that the valves caused the vests to inflate too early in an F-22 flight causing pilots to hyperventilate in the cockpits. The vests help control the breathing of pilots in high G-force environments. However, the valves inflated the vest before the pilots started to experience extreme G-force conditions.

This made the vest feel like a “corset,” Lyon said. For the most part, though, pilots didn’t notice the vests inflate.

Such a simple answer to a problem that has eluded Air Force engineers and scientists for four years has left some Air Force pilots skeptical. An F-16 pilot said the Air Force is either “incompetent for missing this until now,” or “dishonest and trying to sweep something under the rug.”

Read more about the press conference and Lyon’s discussion about the hunt for the problem here.

About the Author

Michael Hoffman
Michael Hoffman is the executive editor at Tandem NSI and a contributor to He can be reached at
  • Brad

    I agree with that last quote, incompetent or implicit. I’ve heard that before lol, but it was used to describe another government, not our own!

  • Andy

    The VALVE are made in China. Do nothing Congress have to get back to work.

    • Raptor Keeper

      You guys are clueless. These valves are NOT made in China!!! And until the huge and extensive LIFE SUPPORT SYSTEMS investigations started in December of 2010, nobody ever took a close look at these G-vests, or ever performed such an extensive investigation on G-forces/vests vs physiology. As a result of these investigations, which involved every military branch and NASA, we found out a LOT about human physiology, and improvements that need to be made to aircraft systems. There were TONS of smaller improvements that were implemented as a result of these investigations, which will save our pilots’ lives in the future. Like Gen. Lyons said – there was no smoking gun, but the biggest contributor was the valve. Which is, by the way re-designed and re-built in the USA.

      So please don’t make general statements if you are not involved in something. And I’m sure you can understand why the government, or anyone involved, is not disclosing the details of what goes on with Top Secret programs. Satisfying your curiosity is a LOT less important than National Security and lives that depend on it!

  • BlackOwl18E

    If it isn’t fully fixed it shouldn’t be flying. My only question here is: Why hasn’t the USAF grounded the F-22s until they find the problem? We don’t exactly need to keep them flying right now and there is no immediate threat that requires them. Is it to save the USAF embarressment?

    • Chris

      How ya gonna find the problem if you don’t fly the planes?

      Taking the planes apart on the ground can only do so much.

      • BlackOwl18E

        Why are ALL of them flying?

    • Feh

      They’ve actually been grounded for the past 4 months because of this issue.

    • Raptor Keeper

      There’s no immediate threat? Just having the around and able to fly is enough of a threat to keep the threats DOWM!

      • BlackOwl18E

        Keeping these jets flying hasn’t done anything. Our Super Carriers have been providing the threat that intimidates our enemies. What I’m wondering is why defense tech hasn’t covered the F-35’s release of a 1,000 lb bomb. I almost can’t wait to provide my 2 cent piece on that.

  • Lance

    I find it funny they pick a valve used on the F-15 yet no Eagle pilots had these problems when they were used.

    • Mike

      That’s because the F-15 doesn’t fly at the higher altitudes, therefore the valve works fine, when you increase the altitude envelope, you have to design for that increase, the engineers who built the thing just used the same part because it was cheaper and THEIR test pilot said it was ok.

      • blight_

        During the prototype stage you generally recycle parts from older aircraft. Once you start testing though, you need to iteratively replace those off-the-shelf ones with parts commensurate with the mission at hand.

        • B.E. McCormick

          A number of instances were reported at landing…

  • stephen russell

    Maybe time to replace ALL valves for F16s & F22s alone & nix for F35 project.

  • Russell Romick

    What about the pilots who experience hypoxia like symptoms sitting in the cockpit on the ground? LMAO. I think the AF thinks we are stupid. Even on 60minutes one of the whistleblower F22 pilots reaffirmed a case of sitting on the ground. I guess they hope noone pays attention. doh.

    • blight_

      In addition to ground crew experiencing it? Hmm.

      Be interested to see if the supplier of RAM reports similar problems.

    • Brian Black

      The AF has proffered the idea that ground crews experiencing the same hypoxia symptoms were in fact only hungry and dehydrated. I shit you not.

      • Chuck

        My dad served as a doctor in the air force. Ground crews get light headed all the time from heat and dehydration. He periodically had to sit down with the ground crew non-coms and say “this is how much water each of your guys needs to drink every 2 hours… this is how many salt tablets they need to take every shift.” Such discussions were generally the result of someone on the ground crew ending up hospitalized in critical condition for heat stroke, dehydration or dilutional hyponatremia (if you drink too much water while sweating heavily, it can result in dangerously low sodium levels.

        It is not uncommon for people for blame a newly publicized cause for symptoms that are not actually new.

        • blight_

          If they admitted those ground crews to the hospital, they would know pretty quick if dehydration and low blood sodium concentrations were to blame. If the problem was not resolved by some saline IV, then…

  • Chris

    I don’t buy that story one bit… it doesn’t even begin to explain why pilots are breathing out high levels of toxins upon leaving the aircraft and why ground crew are experiencing the symptoms. Coupled with the fact that the F-16 pilot said the Air Force was, “incompetent for missing this until now,” or “dishonest and trying to sweep something under the rug.” There it is. Really disappointed, but not surprised.

  • SMSgt Mac

    Suggest everyone first search all the news articlesand the AF presser on this subject before they get the vapors to see just what is being left out of the account offered above.

  • Sergei

    Open window end of problem say good general from old home my world.

  • Tim

    Only time will tell. If so far nothing has happened, then why do people insist that there is still a problem?

    • Mike

      Because everybody wants to be a rockstar but no one wants to pay the dues

  • mpower6428

    in five or 10 years this is gonna be one hell of a story. if any “journelists” see fit to cover it.

    oh well.

  • ltfunk2

    The bottom line: The need to save Lockheed from embarrassment trumps pilots lives.

  • Chris

    Because the solution the AF is giving us doesn’t account for near 50% of the symptoms pilots and crew are having

    • Mike

      If the pilots don’t like the conditions in the cockpit then let them go fly predators

  • Pappa51

    I hope that this solves the problem. Our pilots are the best, and the F-22 is a lot better than most of the stuff you hear on the news or the Web. Could it be that the USAF is playing the old misinformation card on everyone.
    Anyway, I only hope that no more pilots have to pay the price.

  • Hunter76

    Air Force incompetent? No way. But their area of competence is sucking billions of taxpayers’ dollars and never any responsibilities.