[jr2]

Discuss:

EDIT: According to the video, (see vid link two lines down), this is a known problem.  The pilot that died two years ago had a four-second warning before being left without oxygen.  A former USMC fighter pilot explaining the USAF computer simulation of the accident believes the simulation shows the pilot blacked out for at least 15 seconds, and recovered consciousness too late to save the plane.  (video 1:30 thru 2:35)


http://news.yahoo.com/fighter-pilots-claim-intimidation-over-f-22-raptor-123832451--abc-news-topstories.html

-->> Video link: http://abcnews.go.com/Blotter/fighter-pilots-claim-intimidation-22-raptor-jet-concerns/story?id=16294011#.T7CBh-tYuSo

Two F-22 Raptor pilots have said publicly that not only are they afraid to fly the most expensive fighter jets in American history, but the military has attempted to silence them and other F-22 pilots by threatening their careers.

"There have been squadrons that have stood down over concerns. And there's been threat of reprisals," F-22 pilot Josh Wilson told CBS News' "60 Minutes" Sunday. "There's been threat of flying evaluation boards clipping our wings and doing ground jobs. And... in my case, potentially getting booted out of the Air Force.

"So right now there's an example being set of, 'Hey, if you speak up about safety, you're going to be out of the organization,'" Wilson said.

Despite the Air Force's glowing descriptions of the next-generation jet as America's future of air dominance, as an ABC News "Nightline" investigation broadcast last week found, unknown problems with the plane's oxygen system have already contributed to the death of one pilot, the near-death of another and mid-air scares for dozens more.

READ Exclusive: Family Demands Truth in Air Force F-22 Pilot's Death

Wilson and fellow F-22 pilot Jeremy Gordon, both veteran fighter pilots for the Virginia Air National Guard who came forward under whistleblower protection from Rep. Adam Kinzinger (R.-Ill.), have asked not to fly the F-22 anymore, according to CBS News, citing their concerns with the oxygen problem.

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Gordon said that two weeks after he requested not to fly the jet, he was called before a board of officers.

"I was asked to make a decision that day whether I wanted to fly or find another line of work," he said.

Several current and former F-22 pilots contacted by ABC News for its investigation either did not respond or quickly declined to comment on the plane and two relatives of flyers told ABC News that the pilots had been instructed not to speak to the media on penalty of potentially losing their post with the F-22 -- a coveted position despite the safety concerns. One pilot, when initially contacted by ABC News for comment, agreed to speak on the record but only after he checked with the Air Force public affairs office. Since then, the pilot has not responded to any of ABC News' attempts to communicate.

Air Force spokesperson John Dorrian told ABC News he has no information about any pilots being explicitly told not to speak to the media about the Raptor and noted that several F-22 pilots have been made available to the press at Air Force events. Dorrian did say that if a member of the Air Force wishes to speak with the media as a representative of the Air Force, that engagement is conducted through the Air Force public affairs office, but whistleblowers are still protected.

"Corporately, the Air Force position is the Air Force is not going to tolerate any reprisal actions against whistleblowers," Dorrian said.

Since Wilson and Gordon are assigned to the Virginia Air National Guard, Dorrian said he did not have specific information on their case. Officials at the Virginia Air National Guard did not immediately return requests for comment for this report.

Top officials at the Air Force and Lockheed Martin refused to take part in one-on-one interviews with ABC News for its broadcast report, but the Air Force provided a statement last week in which it says the service is committed to "unparalleled dedication to flight safety."

"Flying America's premier fighter aircraft always entails risk but the Air Force has, and always will, take every measure to ensure the safety of our aircrews while delivering air superiority for the nation," the statement said. The Air Force has also stressed that reports of "hypoxia-like symptoms" are exceedingly rare -- more than two dozen compared to the thousands of flights flown without incident.

READ: Air Force's Full Statement in Response to ABC News Investigation

Last week the Air Force officially received the last F-22 Raptor from defense contracting giant Lockheed Martin, completing an order of 187 planes that cost U.S. taxpayers an estimated $79 billion -- meaning that including research, development and production among other costs, each plane has a price tag of more than $420 million. Despite being the most advanced fighters on the planet, none of the planes have been used on a combat mission since they went combat-ready in late 2005. Critics told ABC News that's because the jet was designed to fight rival, sophisticated fighters – an enemy that doesn't exist right now.

READ: Final F-22 Delivered, McCain Says $79B Jets Still Have No Mission

F-22 Pilot Blamed in Fatal Crash After Plane Malfunction

Capt. Jeff Haney was flying the Air Force's next-generation stealth F-22 Raptor on a routine training mission in Alaska in November 2010 when a sudden malfunction cut off his oxygen completely. Capt. Haney never made a distress call but took his plane into a dive and, a little over a minute later, crashed into the winter wilderness at faster than the speed of sound.

After a lengthy investigation, an Air Force Accident Investigation Board could not find the cause of the malfunction but determined "by clear and convincing evidence" that in addition to other factors, Haney was to blame for the crash because he was too distracted by his inability to breathe to fly the plane properly.

READ: Air Force's Accident Investigation Board Report (PDF)

But Haney's sister, Jennifer, told ABC News in an exclusive interview she believes her brother blacked out trying to save himself and said that by blaming him, the Air Force was attempting to deflect attention from the ongoing, mysterious oxygen problem with the costly planes.

"I don't agree with [the Air Force]. I think there was a lot more going on inside that cockpit," Jennifer Haney said. "A cover-up? I don't know. But there's something."

In at least 25 cases since 2008, F-22 pilots have reported experiencing "hypoxia-like symptoms" in mid-air, according to the Air Force. Last year the Air Force grounded the full fleet of F-22s for nearly five months to investigate, but still no one knows what is going wrong, even as the planes are back in the air. Hypoxia is caused by a lack of oxygen to the brain and is characterized by dizziness, confusion, lack of judgment and, eventually, unconsciousness.

In one case before the grounding, a pilot became so disoriented that his plane dropped down and skimmed treetops before he managed to save himself and return to base, an Air Force spokesperson told ABC News. Presumably speaking of the same incident, Gordon told "60 Minutes" the pilot had to be told he had hit the trees -- he didn't remember doing it himself.

Wilson described experiencing apparent hypoxia while in the cockpit as a "surreal experience" and Gordon said the onset is "insidious."

"Some pilots will go the entire mission, land and not know anything went wrong," Gordon said.

To Jennifer Haney, every time an F-22 goes up, it's risking the life of its pilot. She spoke to ABC News because she said she couldn't stand to see another family go through what hers had.

"I know that the Air Force has said that they were very proud to have Jeff and are very sorry for our loss -- well then, in Jeff's name, fix this," she said. "We want to make sure Jeff did not die in vain -- that his death will mean something and that if it saves lives of pilots now, future pilots, then he died for the greater good or something."

The Air Force has already begun to enact changes to the jet in hopes of mitigating the oxygen problem, including adding pilot-monitoring equipment and improving the emergency oxygen system.

But for all their effort, the Air Force still doesn't have what Jennifer Haney said is most important both to her family and to the families of pilots that risk their lives every day at the controls of the F-22: answers.

"I believe Jeff deserves that. That was my baby brother and I believe he deserves that. He deserves the truth to be told as to what happened. Not anybody's guesses," she said. "He deserves the truth. He deserves honor and so do his little girls."

WATCH '60 Minutes': Is the Air Force's F-22 Fighter Jet Making Pilots Sick?

[-Norbert-]

Wrong forum...
This is the General FreeSpace discussion.
The generel discussion for non-freespace stuff is further down.

[General Battuta]

I have been following a bunch of air force dudes discussing this. Opinions are mixed.

[Nuke]

seems you could get around the problem with an emergency o2 tank. stick an oxygen sensor in the mask lines, and if it doesnt detect sufficient oxygen, open up a solenoid valve on the emergency tank, and sound an alarm so the pilot can drop below 10k feet before the tank runs out. this kinda thing is cheap and simple to do with a few off the shelf parts. making it milspec and mounting the hardware, just add a couple of zeros to the end of the price tag.

[Dragon]

That could work as a stopgap, but a more permanent solution would be required sooner or later.

[headdie]

But it would give time for a formal solution to be put into place.

I am more interesting in what could be causing the O2 failures, it's not like its something new and should be so routine on combat craft that beyond poor maintenance just should not fail in any form.  The basics are compressed gas cylinder, hose, regulator and delivery mask.  the only place for electronics is pressure sensor to detect remaining supply and ambient O2 sensor linked to the regulator to keep the O2 levels even, so one moving part and 2 points of electronic involvement.

[Dragon]

Unless the Raptor has some new "improvements" to the O2 system, it's indeed something that has no way to fail. It should be easy enough to check and the problem shouldn't be hard to find. I suspect the pressure and/or the ambient O2 sensor, but only on the basis that everything else can only have easily detected structural failures (it'd be rather embarassing for Lockheed if the hose had a tendency to spring a leak after a certain period of use, plus such a leak should quickly be found). In fact, Nuke's stopgap solution is pretty much how the actual system works, minus the alarm and with a bigger tank.

[Nuke]

But it would give time for a formal solution to be put into place.

I am more interesting in what could be causing the O2 failures, it's not like its something new and should be so routine on combat craft that beyond poor maintenance just should not fail in any form.  The basics are compressed gas cylinder, hose, regulator and delivery mask.  the only place for electronics is pressure sensor to detect remaining supply and ambient O2 sensor linked to the regulator to keep the O2 levels even, so one moving part and 2 points of electronic involvement.

that was my thought, the systems just aren't that complicated. we've been using these systems or similar since ww2. seems like it would be easier to just retrofit the jets with a known reliable oxygen system. even then this is a system you kinda want to have a redundant backup system for. a few thousand dollars is nothing compared to a $420 million dollar jet, not to mention a pilot that cost a fortune to train who would rather not be dead.

[Dragon]

TBH, I wonder what prevents USAF from taking one of those systems out of the plane and putting it in a vaccum chamber, perhaps attached to a G simulator. AFAIK, they're the last thing to fail on most planes, because they're fairly simple, and for a good reason. Unless they overengineered it (like the rest of the plane), testing it shouldn't be difficult.

[LordPomposity]

I'm going to not go out on a limb at all and hazard a guess that some defense contractor who donated to a re-election campaign was awarded a hundred million dollars or so to build an excessively complicated new oxygen system for this plane.

[jr2]

Wrong forum...
This is the General FreeSpace discussion.
The generel discussion for non-freespace stuff is further down.

Apologies. Was in a hurry and skipped "FreeSpace" between "General" and "Discussion".

I find it odd that a stop-gap solution has not been implemented, and, heck, wtf could actually be that wrong with the main system?  Although, maybe the main system extracts O2 from the compressor stage of the engine, like commercial liners do.. idk.

Anyways, blaming a pilot for being distracted by his hypoxia... hmm.

[Thaeris]

I was just about to comment on that... I'm not sure it's just the article's means of spinning things to get a rise out of readers or it's genuinely the case (I should probably try to find official publications...), but regardless it leaves a horrid taste in my mouth.

When the pilot noted a problem with breathing, he presumably put the plane in a dive to get below 10,000 feet, which I believe is the standard protocol for a combat aircraft. If he simply passed out, that might have been the reason for the lack of communication - flight paths on any aircraft are usually stringently monitored, so breaking flight from cruise-at-altitude without a call is very strange indeed. In any sense, the point is he didn't recover... blacking out from lack of oxygen is never your own damn fault, and I'm ashamed of the Air Force if they're passing the blame of mechanical failure onto a pilot qualified to fly what is supposed to be the most potent tactical asset in our arsenal.

[NGTM-1R]

It's probably got more in common with a commercial aircraft system than a simple oxygen bottle. The F-22 is from the post-aerial-refueling age, you'd need a huge amount of oxygen to cover some the possible missions it would have to fly. 18 hours? 22? There's no place to put it all.

Given the known problems with skin separation this sounds like a predictable sort of screwup.

[Thaeris]

Thing is... problem with the O2 system or not... I can't believe pilots are not getting a warning from an internal sensor in the cockpit! And if there is a sensor, it's not acceptable in quality. I'm not sure what the general expected quality of oxygen equipment in fighters has been for the past 50 years is, either. But I can tell you, that for a fighter plane that was designed to operate at high altitudes, yeah... not acceptable.

As far as endurance goes, Introducing a re-breather system in a fighter could probably keep an emergency supply going for a good long while, and not take up too much space (hopefully)... but, regardless... all that R&D, I'm guessing they just bought the system from the lowest bidding subcontractor.

[General Battuta]

I believe the oxygen system is fed off of bleed air from the engine compressor. More details in this whack o text

An Air Force accident report said the F-22, tail number 06-4125, had a bleed air problem that caused both the stealth fighter jet's Environmental Control System (ECS) and On-Board Oxygen Generating System (OBOGS) to automatically shut down, the sources said.

The report has been released to Air Force officials at Pacific Air Forces, but has not been made public, the industry source said. The F-22 fleet was grounded May 3 after pilots suffered more than a dozen hypoxia-like incidents while flying.

Lt. Col. John Dorrian, an Air Force spokesman wrote in an email, "The information provided by your 'industry source' is not a wholly accurate characterization of the crash. However, due to the ongoing Accident Investigation Board process I am not able to provide point-by-point confirmation, as the information is not yet releasable. PACAF is conducting the AIB process and will release appropriate information once the process is complete."

The bleed air system siphons off air from a jet engine's compressor section to generate power, supply oxygen and inert gases, and handle heating and cooling.

If the ECS and OBOGS shut down, the pilot would not have air coming into the cockpit, and would have to switch to his emergency oxygen supply and dive to 10,000 feet, another source said.

"If the ECS is out … there is no conditioned air pressure pushing through the OBOGS, so he would be sucking rubber," the source said. However, as the aircraft descended, "the cabin pressure would be gradually rising as long as the canopy was still intact completely," he said.

But Haney's F-22 never recovered from its dive. The twin-engine jet hit the ground, and it is unclear whether the pilot had switched to his emergency oxygen supply, the industry source said.

"The rate at which he descended, though, he would have been at a hypoxia-safe altitude within time to have not fully succumbed to hypoxia and should have only had symptoms versus unconsciousness," the pilot source said. "The green ring [emergency oxygen bottle] in the Raptor is a tough pull, and it was altered to give the pilot some pressure."

Activating the emergency oxygen system is tricky in the Raptor, the source continued.

"It is a double pull that has to be practiced and experienced a few times before you end up in that bad situation, or you will panic," he said.

The industry source said the report declared that the accident was not related to the OBOGS.

But there are skeptics who say the OBOGS can't be ruled out as a culprit.

"Around May, the aircrew were briefed that the mishap OBOGS unit was operating fine on [Haney's] flight," the pilot source said.

The source said that if the report's findings are accurate, though he is not convinced it is, it could be that other physiological factors with pilot's g-tolerance and the oxygen levels in his body could have played a role in the crash. Haney was attempting a maneuver called a "rejoin" and made a fairly aggressive turn during the procedure, the pilot source said.

"I would have done the same thing with a Raptor in my hands," he said. "It's just that if OBOGS and the whole ECS was working nominally, physiological stuff is what might have crept up on him and impaired his normal ability."

The pilot source said the investigation would have had to determine Haney's oxygen supply and g-tolerance in that exact instance, but a precise assessment would not have been possible because of the condition of the pilot after the crash.

"I don't see how you can absolutely rule out OBOGS by checking a smoked and crushed system and using what aircraft data was available based on a lack of an [Integrated Caution and Warning] showing unacceptable [oxygen] concentration or pressure," the pilot source said. "You have to look at what testing was done to call those concentration and pressure limits as good, and that goes back before the flight of Ship 4001," the first F-22 test plane.

Why Did Bleed Air Fail?

Questions remain as to the nature and cause of the bleed air system malfunction.

Hans Weber, who owns Tecop International, a San Diego-based aerospace consulting firm, said that while bleed air systems are ubiquitous, they are complex and occasionally malfunction.

"It's a fairly complicated system," said Weber, a former member of the U.S. Federal Aviation Administration's Research, Engineering and Development Advisory Committee. "So there can be failures in it."

Bleed air is very hot when it is sucked from the compressor; it goes through a series of heat exchangers to cool it to about 450 degrees Fahrenheit, he said. From there, it is further processed and cooled before it is used. Failures are rare, but they do happen, Weber said.

What is particularly worrisome is that aircraft bleed air systems have built-in safety gear, and whatever this malfunction was, it managed to overcome them, he said.

Further, Weber said that even if the OBOGS is exonerated in this incident, there have been more than a dozen hypoxia incidents. It is possible the problem is related to the other oxygen system incidents, he said.

"Might that apply to the others? Is this an outlier or at the core of the problem?" Weber asked.

[Nuke]

Wrong forum...
This is the General FreeSpace discussion.
The generel discussion for non-freespace stuff is further down.

Apologies. Was in a hurry and skipped "FreeSpace" between "General" and "Discussion".

I find it odd that a stop-gap solution has not been implemented, and, heck, wtf could actually be that wrong with the main system?  Although, maybe the main system extracts O2 from the compressor stage of the engine, like commercial liners do.. idk.

Anyways, blaming a pilot for being distracted by his hypoxia... hmm.

i would assume a military jet wouldnt use bleed air for its oxygen system, to protect the pilot from nuclear/biological/chemical hazards (but im not sure if this is an issue at altitude). but idk, i didnt design it.

It's probably got more in common with a commercial aircraft system than a simple oxygen bottle. The F-22 is from the post-aerial-refueling age, you'd need a huge amount of oxygen to cover some the possible missions it would have to fly. 18 hours? 22? There's no place to put it all.

Given the known problems with skin separation this sounds like a predictable sort of screwup.

of course this is a good point too. but like i said, i didnt design it so i dont know, its probibly all classified anyway.

[General Battuta]

see what i just post (it does use bleed air from the compressor)

[Nuke]

im still reading
i reply to posts in order, in this case i was distracted and hit post before i was done.

sources like that are good to have though. save us time toying with assumptions.

a couple of things, the op article said the aircraft dove in at super sonic velocity. it could be the pilot started his decent, he may have panicked and pushed to hard on the throttle prior to blacking out. you wake up around 10000 feet, flying nose to the ground at super sonic speed. you cannot change direction rapidly, and pulling up at that speed would kill you or tear up the aircraft, not that you would have very much time to react. im surprised the flight computers would let you maintain high throttle in a supersonic dive without locking out the controls and pulling up before the dive becomes a one way shot to hell.

im also wondering if the problem may be co/co2 leakage through the bleed system. less likely, as the compressor is upstream of the burner. another possibility is substandard parts in the high pressure high, temperature part of the bleed system. there was that article awhile back about us military hardware being full of counterfeit chinese parts.

[jr2]

im surprised the flight computers would let you maintain high throttle in a supersonic dive without locking out the controls and pulling up before the dive becomes a one way shot to hell.
Well, in a fighter jet at least, the computer needs to allow pilots room to make pretty crazy maneuvers, as those can be the edge that means they are the one that goes home in an engagement with another fighter.  So the computer can't be too much of a nanny.  Now, if you had it in terrain-hugging mode, it might prevent you from accidentally nosing into the dirt, but I think that'd be a toggleable feature and probably suited more for the F-35 than the F-22...
 there was that article awhile back about us military hardware being full of counterfeit chinese parts.
I was thinking that too.

[headdie]

The article suggests that both the ECS and OBOGS of the O2 supply shut down, suggesting to me a problem in the ECS (if I understand the terminology properly in that it is the nanny system for the cockpit environment) and it is shutting down the air feed to the OBOGS (air processor?) from the engines so probably a software glitch (good luck hunting that down) the article also says it requires pilot intervention to activate the backup O2 supply which is concerning in some respects but it also prevents the computer system from locking out the system.

Another interesting thing is that the article suggests it's an all or nothing failure which I would have thought would be noticeable by the pilot enough so to activate the emergency supply, the only exception would be if the failure happens while manoeuvring, then the pilot has other things to worry about like getting the plane into a level flight which would take critical time.