Home » Aviation » Congress Frustrated at Progress of Fighter Physiological Episode Investigations While Navy Back to Full Pilot Production After T-45C Fixes

Congress Frustrated at Progress of Fighter Physiological Episode Investigations While Navy Back to Full Pilot Production After T-45C Fixes

Pilots perform pre-flight procedures in T-45C Goshawks from Training Air Wing One (TRAWING) 1 on the flight deck of the aircraft carrier USS George Washington (CVN 73) on Dec. 10, 2016. US Navy photo.

WASHINGTON, D.C. – The Navy isn’t moving fast enough to fix the ongoing systemic physiological episodes that have plagued fighter pilots and flight students, members of the House Armed Services Committee said on Tuesday.

The number of physiological episodes suffered by pilots has been on the rise over the last ten years, and the Navy was forced to deal with the issue in April 2017, when a group of more than 100 Navy pilot instructors refused to fly the T-45C Goshawk trainer aircraft due to safety concerns.

Since then, the House Armed Services tactical air and land forces subcommittee has held several hearings but remains dissatisfied with the progress on solving the PE problem, chairman Rep. Michael Turner (R-Ohio) said on Tuesday.

“This has got to be fixed. I don’t have confidence that we’re getting nearer to that,” Turner said.
“This would seem to be something that needs to be done quickly and expeditiously. This should not be a research project. This should be a fix-it project.”

In response, the head of the Navy Physiological Episode Action Team (PEAT) Rear Adm. Sara Joyner told the subcommittee the Navy has brought its T-45 trainer fleet back to full pilot production levels with the installation of CRU-123 solid-state oxygen monitoring units. The units alert the aircrew if oxygen pressure falls and allows them more time to take corrective action to prevent a PE.

“We are very carefully trying to put that training to the max capacity,” Joyner told USNI News following the hearing.
“We’re not only trying to meet what the requirement is, but do more in order to make sure we fill that gap and mitigate it.“

While pilot production is improving, the Navy is still wrestling with PE issues on its fleet of F/A-18 Hornet and Super Hornet fighters and the EA-18G Growler electronic attack aircraft.

As a measure of oversight, Congress ordered an independent NASA report that was released in December to evaluate the Navy’s effort to combat the PE problems in the Hornets and Growlers.

The report was critical of how the Navy focused on trying to find a mechanical defect in the aircraft rather than involve the Navy’s medical community or pay more attention to the human element of the problem.

“Although the Navy has put significant effort into investigating the physiologic episodes, the bulk of their efforts to date have been directed to the aircraft rather than human physiology,” Clinton Cragg, the principal engineer of the NASA Engineering Safety Center who over saw the report, told the panel.
“An unacceptable number of physiological episodes will persist in the F/A-18 program if there continues to be a piecemeal approach to human systems integration… Centering our investigation on the human element revealed new information about the character of physiological episodes.”

Last summer the Navy created Joyner’s current job as a way to ensure the service was holistically looking at the problem from all angles. Whereas the Navy had some success on the material side — now-retired former commander of Naval Air Systems Command Vice Adm. Mike Shoemaker said in the fall that PEs were down significantly after making changes to the OBOGS — the Navy realized the human side was more complex that leaders realized, with factors like hydration and sleep levels contributing to some pilots experiencing PEs in flight conditions where other pilots would experience no symptoms at all.

The efforts for the Hornets, Super Hornets and the Growlers are directed at preventing failures in the two systems related to the two general groups of PEs – those caused by failures of the ”Onboard Oxygen Generation Systems (OBOGS) or pilot breathing gas, and those caused by problems in the Environmental Control Systems (ECS), i.e. – unscheduled pressure changes in the flight station,” according to the service.

Joyner outlined a series of steps the service has undertaken to address both the OBOGS and ECS maintenance as well as planned overhauls for the systems on the Hornets, Super Hornets and Growlers.

In addition, based on NASA report recommendations, the Navy is installing more precise monitoring equipment to gauge pilot breathing for more accurate data.

Still, the effort has several technical challenges: for example, the older designs of the legacy Hornets built in the early 1980s are on paper and on microfiche in the vaults of manufacturer Boeing. While the company is assisting in the effort, Joyner said gathering the material was slow going but the service was committed to the effort.

“This will remain our top safety priority until we fully understand, and have mitigated, all possible PE causal factors. Fleet awareness is high, confidence in their platforms and our processes are improving, protocols are in place and we are focused on mitigating risk, correcting known deficiencies,” Joyner said.

For his part, Turner told the Navy, “help me get a sense that we have things in place that will are going [fix this] that knowing that pilots had to revolt and not fly because the chain of command wasn’t recognizing their complaints and their incidents.”

  • kye154

    ” the Navy realized the human side was more complex than leaders realized”. Really? What planet did these so called “leaders” come from to not know this? Are they even humans to know? Perhaps the Navy should stop flying its trainers altogether, and send the pilot trainees over the to Air Force or NASA to be trained.

    • hollygreen9

      The Navy leaders of today are nothing but a bunch of overpaid politicians. They could suck the chrome off a ball hitch moscratchy.

  • DaSaint

    It took time to get the plans from Boeing? Really? That should have taken a day, maybe two or three. They know where they are. That’s just being obstructionist or fearful of liability.

  • Ulric Roberts

    They might want to compare the physiological qualities of new pilots over the last ten years with those trained in the previous ten year period.

    • RDF

      NAMI has that data going back to Korea.

  • RobM1981

    There is nothing about this that doesn’t smell fishy.

    I’m sure that people, in their hearts, aren’t looking to harm pilots. This seems more like “just the way that things are done, now…”

    The Air Force flies quite a few aircraft with similar flight characteristics to the 18. Like, oh I dunno… the 15 and the 16. Are *they* having this problem? The F-22 did – is it fixed? How did they do that?

    What is different now? The A-4 was certainly as high performance as the T-45 – how did that plane avoid these issues?

    Are the pilots simply complaining more? It doesn’t sound it. It sounds like a real issue.

    The F-35, which should be re-named “Buffalo II” in honor of a former brilliant airframe, can’t be deployed on ships without losing its stealth. The other naval aircraft aren’t providing oxygen to the pilots. The DDG-1000’s are armed with rifles that have no ammunition. The LCS’s – all two classes of them – are an obvious solution searching for a problem.

    And the one class that is brilliant, the Burke’s, are evidently commanded by Mr. Magoo – killing innocent sailors in the process.

    Yet in the face of all of this, the Navy has the audacity to claim that the “sequester” is the problem. They don’t see any waste here at all, do they?


    Sailors being killed in collisions, pilots being deprived of oxygen, LCS’s cruising the globe (when they run) projecting very little power, and a new fighter jet that is neither stealthy (when it loses its skin) nor maneuverable.

    I’m really thrilled to be funding this.

    • RDF

      A4 had LOX.

      • RobM1981

        It sure did. OTOH, it worked. I realize that retrofitting LOX would be very difficult, but that’s the risk taken when you mess around with new technologies. There has to be a Plan B, even if it adds weight and consumes volume. The only unacceptable outcome is “we can’t fly combat aircraft, or trainers.”

        • RDF

          Those green bottles weren’t that big. It’s more mission length I guess. Maybe the tanker can do LOX and O2 refuel. How s that for out of the box?

          • Secundius

            Two “Highly Explosive” Mediums feeding through the Same Refueling “Probe/Drogue” at the Same Time! Yeeeaaahhh? What could possibly go wrong…

          • RDF

            O2 just supports combustion. Remember 8th grade science? Not difficult to imagine one coupling with two hose connections. Get them out of this silly too complex implementation of OBOGS.

          • Secundius

            I thought you were referring to LOX not O2? Boeing has been Testing LOX bottles made of Carbon Fiber since 2013, and Space X used on in 2016 in a Space Launch (i.e. Less Weight)…

          • RDF

            the LOX bottles in Naval Aviation get hauled around the flightdeck in a ratty trailer by two sailors that have been up there doing it for 12 hours.. I dont think carbon fiber is good against knocks and splits and punctures, but I could be wrong. This whole OBOGS is a technology bridge too far… Where were the OPEVAL boys when this system was run out ?

          • Secundius

            Wrap the Bottle in an jacket made of “Magnesium”, which is three time stronger than Steel and three times lighter than Aluminum…

          • El Kabong

            And salt LOVES magnesium….

          • El Kabong

            There’s the logistics involved with storing and transporting LOX or O2.

          • El Kabong


            The Safety Systems folks would demo what happens when a mere drop of LOX comes in contact with fuel, grease or oil.

            Try it.

          • RDF

            It’s just a cryogenic and boils off when pressure is relieved. That is unstable. So it’s nothing to mess about with, but why not consider in flight lox refueling? The geniuses thinking inside the box brought us OBOGS and now, fancy O2 add-on alert monitors. They need to do better.

          • El Kabong

            Yeah, no…

            As hollygreen9 below mentions, go watch “The Man From LOX” video.
            It’s on YouTube.

          • RDF

            That’s an old 50s scare flick.

          • El Kabong

            Oh, FFS….

            The dumb is strong in you…

            Our Safety Systems Techs DEMONSTRATED it to us.

            Take a drip tray, put a tiny amount of fuel, oil or grease in it and put a few drops of LOX on it, and BAM.

            Go ahead, mix some up in your hands.

          • RDF

            If you start to research you will find the LO2 does not explode in combination, but, once it is spilled on or in petroleum products very light pressures will Make it combust. For instance, spill it on asphalt and drive a vehicle over it. The pressure from that will make the appearance of explosion.

          • El Kabong


            Having actually served in the air force and worked on fighters, I can tell you from experience, that LOX can and WILL explode on contact with petroleum.

          • hollygreen9

            Have you ever seen the US Navy film “THE MAN FROM LOX”?

          • El Kabong

            Good stuff!

          • El Kabong

            Didn’t know LOX is HIGHLY explosive when it comes in contact with petroleum, I see.

            A pilot will only use Vaseline lip balm ONCE. 😉

          • RDF

            Lox is a cryogenic. O2 is Lox passed through regulators to turn from cryogenic to normal O2.

          • El Kabong

            LOX is explosive when it comes into contact with petroleum products.

    • Secundius

      I suspect be the T-45C has a “Glass Cockpit”, while the A-4 didn’t…

  • CharleyA

    How about we ensure flight crew are properly rested? Like what the airlines are required to do? Maybe cut down on collateral duties? I know a lot of naval officers pride themselves in the (fewest) number of hours of sleep they require, but then we have ship collisions and PE events… Fix the hardware, but fix the scheduling / manning at the same time.

    • Curtis Conway

      Then the Department Head and Division Officers have to fly while on the cruise. Those other duties do not go away. Some delegate authority better than others, and some have good people working for them they can trust. Not all do! This is a factor as well. Naval Aviation has had this problem since before WWII. Then we listen to the US Air Force pilots complain when they have to deploy.

  • Curtis Conway

    The Navy Physiological Episode Action Team (PEAT) has a tough road to hoe, and they are pursuing moving targets.

    “…the bulk of their efforts to date have been directed to the aircraft rather than human physiology…”. There is no such thing as a Mk I Mod 0 Human Being. Everyone is unique and different. Similarities exist, and there are some general rules that apply to human activities, but when we introduce G-forces, altitude, and so many different physical constructs across multiple models of aircraft that are going through constant improvements, things can get convoluted very quickly via modifications that have inadvertent unintended negative effects.

    All of this activity is based upon a constant (the atmosphere), and hopefully it is staying the same at all locations, or at least that is the assumption.

  • John B. Morgen

    Maybe the Navy should return to the old Skyhawk trainers (TA-4).

    • hollygreen9

      I would love to see some of these kids fly an A3 Skywarrior off of an Essex class carrier.

      • El Kabong

        Try an F-4 off the Ark Royal…. 😉

        • hollygreen9

          I take it that you are a Brit. Am I correct?

          • El Kabong

            Close. 😉

            Think more Bonaventure and Banshees.

  • George Hollingsworth

    Where is the preliminary report on the T-45 Goshawk crash in Tennessee that killed both pilots?

  • George Hollingsworth

    I think a reasonable guess would be that the system, which is supposed to provide an increasing percentage of oxygen to the pilots as the cockpit altitude increases, is freezing during the climb and is only providing the oxygen percentage from the point it was seized. Aviator’s breathing oxygen, whether from a bottle or LOX system, is a mil-spec quantity with well over 99% pure oxygen and strictly controlled trace elements and very little water vapor. The crap given to the Goshawk pilots doesn’t come close to this standard in purity and the water vapor content isn’t considered at all.