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F-22 Raptor info


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From the AP:

ANCHORAGE, Alaska – The Air Force is replacing handles that engage the F-22 Raptor fighter jet's emergency oxygen system after pilots reported feeling lightheaded and the death of a captain whose $143 million aircraft took a nosedive into a mountain range in Alaska.

Capt. Jeffrey Haney was killed in November 2010 during a night mission about 100 miles north of Anchorage. An accident investigation found that the plane's controls and switches contributed to the crash, particularly an emergency oxygen system activation ring on the back edge of the ejection seat.

The report found that the two-step process to manually activate the system required the pilot to pull the green ring up and out of the retaining slot and then pull it directly forward. The Air Force says the latter move may have the same force as pulling a 40- or more pound weight.

While the ring is attached to the seat by a lanyard, if it is dropped it can fall between the seats, making it difficult to retrieve, especially if the pilot is flying at night and wearing bulky winter clothing.

The problem with the system was identified by an independent scientific advisory board that studied the jet's safety issues. It was identified as one of the critical items to be fixed, according to public affairs at Luke Air Force Base in Arizona, which came up with the new, safer handles.

The modification makes it easier for the pilot to access the handle, the military says. The Air Force has ordered 200 handles at a cost of $47 each. They have already been installed in Joint Base Elmendorf-Richardson's 40 F-22s, the Anchorage base that Haney, 31, was attempting to return to when he crashed during a night-time training mission.

The new handles also provide a better grip, especially when the pilot is wearing cold weather gear, according to information provided by Luke Air Force Base.

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  • 2 weeks later...

USAF vows to discover root cause of Raptor's maladies

By: Dave Majumdar Washington DC

03/29/2012

(Flight Global)

A US Air Force Scientific Advisory Board (SAB) panel investigating a series of hypoxia-like incidents afflicting pilots flying the Lockheed Martin F-22 Raptor has not discovered what is causing the problem, but service officials vow they will find the root cause.

"I am convinced there is a root cause," says Maj Gen Charles Lyon, Air Combat Command's (ACC) director of operations. "I want everyone to know--particularly those who operate it and their families--we will not rest until we find that root cause."

The USAF is continuing to test the F-22's life-support systems to try to determine what is still causing these "physiological incidents."

Those efforts started in September 2011 under the auspices of ACC, says retired Gen Greg "Speedy" Martin, who led the SAB study. "Those are ongoing today," he says.

The most recent of these physiological incidents happened on 26 March where a pilot at Joint Base Langley-Eustis in Virginia had to declare an emergency after his pulse-oximeter alerted him that there might be a problem. The small device is part of the new ensemble of safety gear F-22 pilots are now required to fly with to mitigate the potential risk from life-support system anomalies.

The USAF first noticed a pattern of unexplained hypoxia-like physiological incidents in April 2008. The service initially restricted the F-22 fleet to altitudes below 25,000 ft but eventually grounded the jet in May 2011 after a series of some 14 incidents. The USAF lifted the flight-ban last September after taking precautionary measures such as installing activated-charcoal filters, oxygen sensors, and having pilots wear a pulse-oximeter. But despite the "mitigation efforts," there continues to be incidents recorded every month-which have prompted a number of temporary local groundings by individual wing commanders.

"If there is any indication of abnormal oxygen levels, we terminate the flight," Lyon says. A team of medics will greet the pilot upon landing to quickly run tests and make sure that he or she is treated if need be.

Lyon says that there are only incidents on 0.1% of flights and pilots have flown over 10,000 sorties since September. Lyons says the F-22 is now safer to fly than it ever has been before.

Some of the "findings" of the SAB to date include the fact that the Raptor's onboard oxygen generation system (OBOGS) and emergency oxygen system were not classified as safety critical items, according to a document released by the USAF. Additionally, there is no backup system that automatically supplies oxygen to the pilot if there is a failure of the primary life-support system. Nor was there a requirement to inspect or maintain OBOGS components until recently.

"It was a fly to worn, fly to fail system," Lyon says. "We now have routine inspections."

But perhaps more importantly, there is a general lack of institutional expertise in the field of aerospace physiology and human systems integration. And in the case of the Raptor, the modelling, simulation and integrated hardware testing of the Raptor's life-support system "were insufficient to provide an 'end to end' assessment of the range of conditions likely to be experienced by the F-22," the document reads.

"During that same period of time, we reduced the emphasis and numbers of people associated with aviation physiology research and science," Martin says "That needs to be re-established."

Part of the problem is that the Raptor routinely operates above the normal 50,000 ft operational ceiling of conventional fighters like the F-15 or F-16, Lyon says. How life-support systems behave at those altitudes is not understood very well, he says. This is particularly true of the Raptor's systems which were designed to operate in a chemical and biological warfare environment and thus require the OBOGS to supply a constant pressurized oxygen-mix to the pilot rather than blending it with cabin air.

While Martin says the Raptor's exact ceiling is classified, it is known that USAF regulations restrict the jet to 60,000 ft. Raptor pilots receive a waiver to fly the jet above 50,000 ft while wearing the Combat Edge g-suit-which counts as a partial pressure suit for the USAF's purposes. The restriction is due to the Armstrong Limit, which is found at an altitude of between 62000ft and 63000ft, where the outside air pressure is so low that water will start to boil at 37°C (98.6°F).

While the USAF continues to investigate, the service has a set of recommendations from the SAB which it is implementing. These include developing a new backup oxygen supply, developing new standards for breathable cockpit air supply, adding an automatic ground collision avoidance system to the jet, and installing a new handle for the troublesome emergency oxygen supply.

70% of the jets have the new handle-which cost $47 a piece-and the rest will have it in a couple of weeks, Lyon says.

There are a host of other recommendations that the USAF is implementing. The service is establishing quarterly review to monitor how well the USAF is doing in implementing the SAB recommendations.

/edit to fix link

Edited by Daredevileng1
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Part of the problem is that the Raptor routinely operates above the normal 50,000 ft operational ceiling of conventional fighters like the F-15 or F-16, Lyon says. How life-support systems behave at those altitudes is not understood very well, he says

Haven't the U-2's been operating well above that altitude since the 1950's? Seems a litle suspect.

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Some of the "findings" of the SAB to date include the fact that the Raptor's onboard oxygen generation system (OBOGS) and emergency oxygen system were not classified as safety critical items, according to a document released by the USAF. Additionally, there is no backup system that automatically supplies oxygen to the pilot if there is a failure of the primary life-support system. Nor was there a requirement to inspect or maintain OBOGS components until recently.

"It was a fly to worn, fly to fail system," Lyon says. "We now have routine inspections."

For fuck's sakes, I work on helicopters with more stringent O2 system inspection criteria than what the Raptor once had.

No one thought the O2 system, on an aircraft with the operating envelope the Raptor has, was a "safety critical item"??

UFB...

edit:

Haven't the U-2's been operating well above that altitude since the 1950's? Seems a litle suspect.

And the SR-71. I guess Lockheed has forgotten (or flat-out ignored) some of the things they learned over the years...

Edited by JarheadBoom
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And the SR-71. I guess Lockheed has forgotten (or flat-out ignored) some of the things they learned over the years...

Yep, it took them two years to get the A-12 flying Mach 3+ at 69,000 ft, but in 26 years they haven't been able to get the environmental system in the F-22 to work.

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The U-2 and SR-71 operate(d) at those altitudes, but a pressure suit was always involved. Raptor pilots wear typical fighter egress gear...flight suit, helmet/mask, harness, g-suit...that's it.

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The U-2 and SR-71 operate(d) at those altitudes, but a pressure suit was always involved. Raptor pilots wear typical fighter egress gear...flight suit, helmet/mask, harness, g-suit...that's it.

Which is absolutely retarded.....trust a U-2 bubba. The bros out here at Beale have a pretty good idea what is happening to these guys, and it ain't just hypoxia. Granted, you definitely need a G-suit to fly the Raptor, but operating at those alts without a full pressure suit and a pre breathe is risky business.

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Yet another "nothing to see here" story by Big Blue:

http://abcnews.go.com/Blotter/22-fighter-ready-war-mystery-problem-air-force/story?id=16031774

America's most expensive fighter plane is ready for combat despite some of its pilots experiencing repeated and mysterious apparent breathing problems that have put a quick end to multiple training missions, Air Force officials said today at a special briefing.

In nearly two dozen cases in the past four years, pilots have reported experiencing "hypoxia-like" symptoms in the $143 million-a-pop stealth F-22 Raptor. Though the incidents are extremely rare, the Air Force is so concerned that they've taken a "911 call approach" – meaning that if a pilot gets the slightest indication that anything is wrong, he's directed to end the training mission and turn back to base. The fleet of next generation fighters, which cost $77.4 billion total, have been considered combat operational since 2005, but none have been used in a single combat mission from Iraq and Afghanistan to Libya.

That doesn't mean the F-22 couldn't go to war at a moment's notice, Air Force Maj. Gen. Noel Jones said today.

"If our nation needs a capability to enter contested air space, to deal with air forces that are trying to deny our forces the ability to maneuver without prejudice on the ground, it will be the F-22 that takes on that mission," Jones, Director of Operational Capability Requirements, said at a special briefing at the Pentagon held to address concerns with the beleaguered F-22. "It can do that right now and is able to do that without hesitation."

Air Force officials also unveiled the findings of a Scientific Advisory Board Study, which was convened to investigate the plane's life support systems. The study, led by Gen. Gregory Martin (Ret.), failed to discover the source of the oxygen problems but listed several related shortcomings with the plane and announced 14 different recommendations.

At the same briefing, the top Air Force official in charge of F-22 operations, Maj. Gen. Charles Lyon, said he stood behind a controversial Air Force investigation report that blamed an F-22 pilot for the crash that took his life, despite the malfunction that completely shut off his oxygen. Capt. Jeff Haney died when his plane crashed into the Alaskan wilderness in November 2010.

The Pentagon Inspector General's office is reviewing the Air Force's investigation, the first such major review in nearly two decades.

Recently the Air Force announced it was replacing the emergency oxygen system handles in all of its F-22s. In Haney's case the emergency oxygen system was never deployed, and the Air Force report had noted that pilots may have difficulty reaching the handle in their cumbersome winter gear.

After a quick succession of safety scares in the last days of April and the beginning of May in 2011, the Air Force grounded the full fleet of F-22s while it investigated the "physiological events" the pilots had reported. But after nearly five months of intense testing and evaluation that produced no smoking gun, the Air Force cautiously allowed the planes back in the air.

The problem, however, has persisted. In at least nine other incidents since the grounding, pilots have reported the "hypoxia-like" symptoms, according to the Air Force. Hypoxia is caused when the brain is deprived of oxygen, causing disorientation, dizziness, poor judgment, and, eventually, unconsciousness.

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Jones said that flying all fighter planes is dangerous, but maintained that even though the problem has not been solved, pilots are "absolutely not" being put at additional, unnecessary risk by flying training and homeland security missions in the planes.

"Pilots are at risk every time that we strap an airplane on… [W]hat we do is critical to our nation," Jones said. "And we are in full belief that the steps that are in place by Air Combat Command, the recommendations that General Martin's board came up with, have given us a very safe airplane while we work to ultimately determine what the root cause is. This airplane is safe and capable of flying."

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... in the $143 million-a-pop stealth F-22 Raptor.

... The fleet of next generation fighters, which cost $77.4 billion total,

I'm no math major,... but with 187 aircraft purchased, that's a rather optimisitic price tag.

By about a third.

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The U-2 and SR-71 operate(d) at those altitudes, but a pressure suit was always involved. Raptor pilots wear typical fighter egress gear...flight suit, helmet/mask, harness, g-suit...that's it.

I'm aware of those things. My point is that I'd be willing to bet the O2 systems on those jets were considered safety critical items from the start, not only as a result of a Scientific Advisory Board convened after metal was bent and life was lost.

edit: grammar, placement of words within sentences, spelling, etc.

Edited by JarheadBoom
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  • 1 month later...

"Although the first F-16 had its first operational flight in 1970, the combat edge aircrew flight equipment, which was optimized for high-G flight, wasn't fielded until about 1988, Lyon said."

So...what you are saying is the viper flew its first operational flight a full four years before its first flight ever....or is someone not proofreading?

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The U-2 and the Sled use LOX... not OBOGS.

I don't know much about OBOGS.

But I do know the LOX system works well.

That price tag is the "flyaway cost"....the amount paid for production not including R&D

"Flyaway cost" is what they call it? I call it "misleading".

These jets cost at least $330M each.

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