Japan Picks F-35 as Mainstay Fighter: Reports

TOKYO - Japan has chosen the U.S.-made F-35 stealth jet as its next-generation mainstay fighter in a multibillion-dollar deal, reports said Dec. 13.

The Defense Ministry picked the jet made by Lockheed Martin to replace its aging fleet of F-4 jets over two rivals, the Boeing-made F/A-18 Super Hornet and the Eurofighter Typhoon, the Yomiuri Shimbun said.

Japan's biggest daily said the Defense Ministry had "agreed in principle" to select the F-35, with a formal announcement expected Dec. 16 at the Security Council of Japan, chaired by Prime Minister Yoshihiko Noda.

Kyodo News cited unnamed government sources as saying the ministry had decided to buy 40 F-35 fighters, while the Nikkei business daily said only that the jet remained a "prime candidate."

Earlier reports said Japan could buy as many as 50 new jets, equipped with stealth technology, with a price tag of more than $6 billion.

A Defense Ministry spokesman on Dec. 13 declined to confirm the reports, saying: "We are still trying to do our best to make a final decision by the end of this year."

And Chief Cabinet Secretary Osamu Fujimura denied the reports that a final decision had been made, Dow Jones Newswires said.

The F-35, the most expensive weapons program in Pentagon history, has been plagued by cost overruns and technical delays.

The jet, co-developed with British defense giant BAE Systems, is the most expensive among the three candidates, with a price tag estimated at $113 million per aircraft.

Japan initially aimed to acquire the F-22 stealth fighter to renew its fleet, but U.S. law prohibits exports of the jet because the U.S. has said it would halt production of the model.

U.S. Air Force Inspecting F-22 Oxygen Systems

The U.S. Air Force is inspecting the emergency oxygen system on its F-22 Raptor air-superiority fighters.

AN F-22 RAPTOR awaits release from a hangar at Holloman Air Force Base, N.M., in September. (Senior Airman DeAndre Curtiss / U.S. Air Force)

Colloquially referred to as the "green apple" by pilots, the system is a self-contained supply of liquid oxygen mounted on the jet's ejection seat and is used in case there is a failure of the main life-support system. By necessity, it is separate from the aircraft's main oxygen systems, which have been under investigation for much of the year due to a string of airborne incidents where pilots have experienced symptoms resembling hypoxia.

"The Air Force is implementing an immediate action time compliance technical order (TCTO) on the F-22 backup oxygen system," a Dec. 8 Air Combat Command (ACC) release said. "This system is known as the Emergency Oxygen System (EOS) and is designed to be used on rare occasions when pilots experience indications or physiological symptoms that suggest there may be a problem with their air supply."

Air Force spokesman Scott Knuteson said that since the Raptor fleet returned to the air in September after a four-month grounding, pilots has been using the backup system more often than usual.

"We have adapted procedures to use the EOS as a precautionary measure to further protect pilots when they receive indications that physiological incidents may occur," the release reads.

However, even then the emergency oxygen system has not been used that often since the jets started flying again, Knuteson said. The pilots only use the system if a problem is detected, he said.

"We have used the EOS on less than one percent of the flights since we returned to flying status and experienced performance anomalies on a small number of EOS activations," the ACC statement reads. "These anomalies have been analyzed by technicians, and corrective measures have been validated and verified."

The inspection was ordered "simply as a prudent step to ensure the full functionality of the EOS given increased usage under current operating procedures," the ACC statement reads.

"As of Dec. 7, approximately 85 percent of the F-22s' EOS bottles had been inspected," Knuteson said. "The main focus of the TCTO is inspecting the EOS bottles and returning them to service."

In the meantime, Lockheed Martin is still delivering new Raptors to the Air Force. One of the newest jets was supposed to arrive at Langley on Dec. 8, but was delayed and will now arrive next week, said Lockheed Martin spokeswoman Alison Orne.

The service currently has 175 Raptors. Of the remaining aircraft to be delivered to the service, tail numbers 4186, 4187, 4189, 4191, 4192 and 4194 will be delivered to Joint Base Langley-Eustis, Va., tail 4188 will be delivered to Nellis Air Force Base in Nevada, while tails 4190, 4193 and 4195 - the last Raptor to be built - will be delivered to Joint Base Elmendorf-Richardson in Alaska.

F-22 Production Line Back on Track: Lockheed

Lockheed Martin's F-22 Raptor production line is back on track after the U.S. Air Force's fleet-wide grounding of the jet had disrupted deliveries to the service, the company said.

RAPTOR TAIL NUMBER 4183 is seen being delivered to the U.S. Air Force on Nov. 15. (Rita Nicholas-King / Lockheed)

"We are delivering jets," said Lockheed spokeswoman Alison Orne. "The last one delivered was 4185. 4195 will be delivered in late spring 2012."

Tail number AF 09-4185 has technically been delivered with the signing of a DD-250 form, but the stealthy fifth-generation fighter is currently undergoing government flight tests. After the completion of the tests this week, the Air Force's 1st Fighter Wing will fly the jet to Langley Air Force Base, Va., where it will be based.

"It is scheduled to depart for Langley on Dec. 8," Orne said.

The final Raptor to be built, AF 09-4195, will also be delivered to Langley, where it will fly with the 1st Fighter Wing's 27th Fighter Squadron, the service's oldest fighter unit. It is expected to be delivered in Spring 2012, according to Lockheed.

2 More 'Physiological Incidents' Related to F-22

The U.S. Air Force's fleet of stealthy F-22 Raptor fifth-generation fighters has suffered two additional "physiological incidents" since Nov. 21, the service confirmed Dec. 2.

"Since 21 Nov., there have been two physiological incidents and no events of interest," said Air Combat Command spokeswoman Kelly Sanders in an emailed statement.

Since the F-22 returned to flight in September after a four-month grounding, the Air Force has maintained two listings for problems arising from operating the jet. The jet was originally grounded in May after more than a dozen pilots suffered symptoms resembling hypoxia.

"Under the current protocols established to monitor F-22 operations since their return to flight, occurrences are categorized into events of interest and physiological incidents," Sanders wrote. "An event of interest is an aircraft indication, system malfunction or a data point that has not caused symptoms of hypoxia nor caused any danger to the pilot or aircraft, but is noteworthy for data collection and further analysis."

However, because of the Raptor's unresolved oxygen system problems, a separate category has been established for incidents that resemble hypoxia.

"Any event of hypoxia or hypoxia-like symptoms during pre-flight activities or a mission would be categorized by Air Force Instructions as a physiological incident," Sanders wrote.

She noted that none of the most recent incidents caused any damage. Air Force sources who tipped off Defense News to these events had alluded to ground crews becoming ill when performing maintenance operations with the engines running. An Air Force official confirmed that was the case with a separate incident. However, the two most recent cases Air Combat Command referred to happened in the air.

"None of these incidents resulted in harm to a person or aircraft," Sanders wrote. "There is a rigorous process of collecting and analyzing operational, maintenance, and physiological data relevant to any incidents, which typically takes several weeks to complete and may or may not produce actionable information."

$24M Awarded to Find Cause of F-22 Oxygen Problem

Lockheed Martin has been awarded an F-22 Raptor sustainment contract for $24 million to find the root cause of the fifth generation air superiority fighter's oxygen system among other things.
The company "is being awarded a $24,363,993 cost-plus-fixed-fee contract modification for the F-22 Program to provide sustaining engineering and depot partnering task associated with non-destructive inspection organic capability, hypoxia root cause analysis, titanium crack growth, site activation, slider seals, and radar cross section turntable," reads a Defense Department contract announcement posted on defense-aerospace.com.

The release was issued on Oct. 26.

USAF Grounds F-22s at Va. Base

U.S. Air Force F-22 Raptors at the 1st Fighter Wing, Joint Base Langley-Eustis, Va., have once again been grounded, service officials confirmed Oct. 21.

F-22 Raptors taxi April 10 during an operational readiness inspection at Joint Base Langley-Eustis, Va. The commander of the 1st Fighter Wing made the decision to ground the Langley-based F-22s. (Airman 1st Class Teresa Zimmerman / U.S. Air Force)

Air Force spokesman Maj. Chad Steffey said that the grounding decision is limited to the Virginia base. A spokesman for Air Combat Command confirmed that the wing's commander, Col. Kevin Robbins, made the decision after an incident.

While details were not immediately available, Air Force officials confirmed that one of the wing's pilots appeared to have suffered an oxygen-related problem.
The Air Force's Raptor fleet was only cleared to resume flight operations last month after a four-and-a-half month grounding. The stealthy fifth-generation fighter was originally grounded May 3 after about a dozen pilots suffered "hypoxia-like" symptoms.
The Air Force is still investigating the problem with the F-22's oxygen system, but had cleared the aircraft to fly because service officials felt that the risk factors had been mitigated. However, the Air Force has not determined what is causing the problem with the jet's oxygen systems.
"There is no conclusive cause or group of causes that has been established for the incidents that prompted the stand-down earlier this year," spokesman Scott Knuteson said in an emailed statement. "We've therefore made the decision to resume operations while implementing improvements to the aircraft's life support systems and carefully collecting and analyzing operational, maintenance and physiological data for all Raptor flights - more than 1,300 missions since the return to flight."
However, as a condition to allowing flights to resume, Air Force leaders have enabled operational commanders to suspend operations as needed.
"Part of our protocol is to allow units to pause operations whenever they need to analyze information collected from flight operations to ensure safety," Knuteson said. "That is what is happening at Langley at the moment, and we support that decision."
One precaution the service took when returning the jets to service was to add carbon filters to the pilot's oxygen supply, one source said. Additionally, pilots were required to give blood samples to use as a baseline to measure against in case of future incidents and are now required to wear a device called a pulse oximeter. The device is supposed to alert the pilot if there is a physiological problem.
However, numerous sources had voiced their misgivings about the return to flight arrangements.

Toxins Grounded F-22s: Sources

The U.S. Air Force's fleet of F-22 Raptor fighters has been grounded since May 3 due to toxins entering the cockpit via the aircraft's life support systems, sources with extensive F-22 experience said.

Service leaders grounded the stealthy twin-engine fighter after pilots suffered "hypoxialike symptoms" on 14 occasions. The incidents affected Raptor pilots at six of seven F-22 bases; the exception is Tyndall Air Force Base, Fla.

But despite an investigation that has spanned nearly three months, no one yet knows what toxin or combinations of toxins might have caused the incidents, nor is it clear exactly how the chemicals are entering the pilots' air supply, sources said.

Toxins found in pilots' blood include oil fumes, residue from burned polyalphaolefin (PAO) anti-freeze, and, in one case, propane. Carbon monoxide, which leaves the blood quickly, is also suspected.

"There is a lot of nasty stuff getting pumped into the pilots' bloodstream through what they're breathing from that OBOGS [On-Board Oxygen Generation System]. That's fact," one former F-22 pilot said. "How bad it is, what type it is, exactly how much of it, how long - all these things have not been answered."

The blood tests were performed after each of the 14 incidents in which pilots reported various cognitive dysfunctions and other symptoms of hypoxia. One couldn't remember how to change radio frequencies. Another scraped trees on his final approach to the runway - and later could not recall the incident.

"These guys are getting tested for toxins and they've [gotten] toxins out of their bloodstreams," the source said. "One of the guys was expelling propane."

This source, along with the others, requested anonymity for fear of retribution.

The line of inquiry may shed new light on the death of Capt. Jeff "Bong" Haney, a 525th Fighter Squadron pilot who was killed when his F-22 crashed last November near Anchorage. Sources said that in Haney's last few radio calls before his jet disappeared, he sounded drunk, a classic sign of hypoxia. Haney was known as a prodigiously skilled aviator who was in line to attend the elite Air Force Weapons School.

Air Force officials have said they have not yet completed the investigation into the crash.

Asked for comment about the possibility that F-22 pilots had been exposed to carbon monoxide, an Air Force spokesman, Maj. Chad Steffey said, "The safety of our aircrews is paramount, and the Air Force continues to carefully study all factors of F-22 flight safety."

Asked about other toxins, Steffey referred questions to the Air Force Safety Center at Kirtland AFB, N.M., where officials did not repond by press time.

Officials with Lockheed Martin, which builds the aircraft, said they are cooperating with the investigation but cannot comment further.

Carbon Monoxide?

Beside the various toxins found in the pilots' blood, carbon monoxide is another potential cause of the hypoxia incidents.

The gas, one of many generated as exhaust by the plane's jet engines, might be getting into the cockpit, sources said.

Part of the problem, at least for pilots flying from Joint Base Elmendorf-Richardson, Alaska, where many of the known incidents have occurred, may be the startup procedures used in winter, one source said.

Because of the harsh climate, pilots often start their jet engines inside a hangar before taking off. That could allow exhaust gases to be trapped in the building, sucked back into the engines, and ingested into the bleed air intakes that are located within the engines' compressor sections that supply the OBOGS, sources said. The layout, sources added, is standard for modern jet aircraft.

But another source said that many of the hypoxia incidents have occurred well into flights or even during a day's second mission, long after the plane has left the Elmendorf hangar.

The U.S. Navy had problems with the OBOGS on its F/A-18 Hornet, which sucked carbon monoxide into its oxygen system during carrier operations. Between 2002 and 2009, Hornet aviators suffered 64 reported episodes of hypoxia, including two that killed the pilots, according to the July-August 2010 issue of "Approach," a Navy Safety Center publication.

The Navy modified the planes' OBOGS, has had no recent similar incidents and is not currently investigating the systems, Naval Air Systems Command officials said.

USAF Expands Investigation

In January, a safety investigation board led by Maj. Gen. Steven Hoog began looking into the the OBOGS on the F-16, F-15E and F-35 fighters; the A-10 attack jet and the T-6 trainer, according to May statements by officials with the service's Air Combat Command, which oversees combat aircraft.

In May, Air Force Secretary Michael Donley had ordered the service's Scientific Advisory Board to conduct a "quick-look study, gather and evaluate information, and recommend any needed corrective actions on aircraft using on-board oxygen generation systems," according to a July 21 statement by service officials.

The release indicated that the service is now looking at more types of aircraft: the B-1 and B-2 bombers and the CV-22 tilt-rotor and "other aircraft as appropriate."

According to the release, the investigation is conducting a "series of carefully controlled in-flight tests, the team will examine the subsystems identified in reported incidents. These include the pressurization system, mask and cockpit oxygen levels."

The release said the Scientific Advisory Board investigation followed the grounding of the F-22 fleet, but did not say whether it superseded, replaced or is merely accompanying the Hoog investigation.

One source said that F-22 test pilots at Edwards AFB, Calif., last week started flying sorties as the investigate OBOGS concerns as part of the Air Force safety investigation.

Air Force officials have confirmed only that some test pilots at the base are flying their jets under a special waiver granted to them to test an unrelated software upgrade.

However, the operational fleet remains grounded, with pilots and ground crews practicing in simulators as much as they can. But that is not a real solution because the pilots won't be able to maintain currency, one former F-22 pilot said.

"After 210 days, they've got to start retraining everybody," he said.

It would take weeks for the instructor pilots at Tyndall to re-qualify themselves and then start to train others, the former pilot said. Pilots with lapped currencies would be re-qualifying each other.

It would take four to six weeks afterward to re-qualify the operational squadrons. Service officials confirmed that 12 Raptors are stranded at Hill AFB, Utah, but declined to identify their squadron. The jets came to the desert base for a Combat Hammer exercise in which pilots and ground crews practice loading and releasing live air-to-ground weapons. Service officials said the jets are from the 1st Fighter Wing at Langley AFB, Va.

Meanwhile, Lockheed can't deliver new Raptors to the Air Force because the company and the Pentagon's Defense Contract Management Agency are unable to fly required test sorties needed to certify the jets meet specifications. Four aircraft have technically been delivered to the service but can't fly to their new home at Langley AFB.

At least two additional aircraft have been completed but remain at the factory undelivered.

USAF Suspects Carbon Monoxide in F-22 Grounding

The prolonged grounding of the U.S. Air Force's F-22 Raptor fleet may be due to carbon monoxide entering the cockpit via the aircraft's oxygen system, two sources said.

Investigators say carbon monoxide may have caused the grounding of the F-22 fleet. The gas generated by the planes' jet engines may have gotten into cockpits at a base in Alaska, where pilots often start the engines inside a hangar before takeoff. (U.S. Air Force)

Service leaders grounded the stealthy twin-engine fighter May 3, after 14 incidents when F-22 pilots suffered "hypoxia-like symptoms."

Air Force officials initially suspected a problem with the aircraft's On-Board Oxygen Generation System (OBOGS), but that is looking less likely, the sources said.
Instead, investigators now suspect that carbon monoxide generated by the plane's jet engines is getting into the cockpit.
Part of the problem may be the procedures used at Elmendorf Air Force Base, Alaska, where most of the known incidents have occurred. Because of the harsh climate, pilots often start their jet engines inside a hangar before taking off. Investigators suspect that exhaust gases are getting trapped in the building and subsequently sucked back into the engines, where they enter the bleed air intakes that supply the OBOGS, sources said.
The design and placement of the intakes, which are located within the engines' compressor sections, are fairly standard for jet aircraft.
There is no immediate fix in sight, sources said.
Asked for comment, an Air Force spokesman said he had no further information at this time.
"The safety of our aircrews is paramount, and the Air Force continues to carefully study all factors of F-22 flight safety," said Maj. Chad Steffey.
However, a July 21 press release says Air Force Secretary Michael Donley has ordered the service's Scientific Advisory Board to conduct a "quick-look study" of "aircraft using on-board oxygen generation systems."
One aviation safety expert said that if the hypoxia is being caused by carbon monoxide in the cockpit, the gas is likely being generated by the plane's engines.
"I would think that it has something to do with exhaust flow somehow getting into the oxygen generating system," said Hans Weber, who sat on the U.S. Federal Aviation Administration's Research, Engineering and Development Advisory Committee, and is president of Tecop International, a San Diego consulting firm.
Even a small amount of the colorless, odorless gas can have serious effects, Weber said.
"It doesn't take a large concentration of carbon monoxide to start affecting people, making them ill - and not just ill but really diminishing their ability to perceive anything."
Weber said the difficulty of the fix will depend on the problem.
If the carbon monoxide is being ingested because the engines are being started in confined spaces, a fix could be as simple as moving the jet outside, Weber said. If the engine must be started inside the hangar, the startup of the oxygen system might be delayed until the jet is out in the open, he said.
But if dangerous levels of carbon monoxide are entering the cockpit despite these changes, the Air Force might have to add bulky cartridges or scrubbers to the life-support system, he said.
The U.S. Navy has had similar problems with the OBOGS on its F/A-18 Hornet, which sucked carbon monoxide into its oxygen system during carrier operations.
Between 2002 and 2009, Hornet aviators suffered 64 reported episodes of hypoxia, including two that killed the pilots, according to the July-August 2010 issue of "Approach," a Navy Safety Center publication.
Some 77 percent of the incidents happened in single-seat Hornets, which saw 3.2 incidents per 100,000 flight hours. The two-seat version saw 1.7 incidents per 100,000 flight hours.
According to Navy documents, "Prolonged exposure to jet engine exhaust while sitting behind another aircraft waiting to take off and operating with low bleed air pressures can result in carbon monoxide (CO) breaking through … into the pilot's breathing gas."
The Navy modified the planes' OBOGS to fix the problem, has had no recent similar incidents, and is not currently investigating the systems, Naval Air Systems Command officials said.

USAF Expands Oxygen-Systems Investigation

The U.S. Air Force has released a few additional details about its safety investigation into aircraft oxygen systems.
In May, the service's Air Combat Command had said that a safety investigation board, led by Maj. Gen. Steven Hoog, had been looking into the oxygen systems on a number of Air Force aircraft since January.

Now a July 21 press release says Air Force Secretary Michael Donley has ordered the service's Scientific Advisory Board to conduct a "quick-look study, gather and evaluate information, and recommend any needed corrective actions on aircraft using on-board oxygen generation systems."
The release said the Scientific Advisory Board started its study in May, but not whether it supersedes, replaces or merely accompanies the Hoog investigation.
The release indicates that the service is now looking at more types of aircraft. Previously, Air Force officials had said the investigation concerned the On-Board Oxygen Generation Systems (OBOGS) on the F-16, F-15E, A-10, F-35 and T-6 aircraft.
The release adds the B-1 Lancer, B-2 Spirit, CV-22 Osprey and "other aircraft as appropriate."
The Scientific Advisory Board study is being led by retired Air Force Gen. Gregory Martin, who commanded Air Force Materiel Command and U.S. Air Forces in Europe.
"The team will expand on previous safety and accident investigations and may include other agencies or industry partners," the Air Force release said.
According to the release, the investigation will conduct a "series of carefully controlled in-flight tests, the team will examine the subsystems identified in reported incidents. These include the pressurization system, mask and cockpit oxygen levels."
The Air Force, which grounded its F-22s in May, has not grounded any other types in connection with the investigation into oxygen systems.
Earlier July 21, the Air Force had said it had no additional information when asked whether carbon monoxide leaking into the cockpit was the most likely culprit behind the F-22 grounding.

F-22 Deliveries Halt as Grounding Continues

Deliveries of F-22 Raptors to the U.S. Air Force have been halted due to the continuing suspension of flight operations for the stealthy fifth-generation air superiority fighter.

A new F-22 Raptor sits at the Lockheed Martin production facility at Marietta, Ga., one of four that have technically been delivered to the U.S. Air Force but have yet to fly to their home base at Langley AFB, Va., because of a service-wide grounding (Lockheed Martin)

Even though manufacturer Lockheed Martin continues to build the aircraft at its Marietta, Ga., factory, the company is unable to do required flight testing for each aircraft as it leaves final assembly. Nor can government test pilots from the Pentagon's Defense Contract Management Agency (DCMA) fly their acceptance flights for new aircraft as they are readied for delivery.

"Our final assembly is scheduled through December 2011. That is still ongoing at Marietta. We delivered aircraft 4181, and that was on June 22, to the Air Force, so they have that as their aircraft," said Lockheed spokeswoman Stephanie Stinn. "After that aircraft, we can't do the required acceptance flights."
Technically, four aircraft have been delivered to the Air Force, but are being stored at Marietta pending the lifting of the flight restrictions. When the Air Force resumes F-22 flight operations, those aircraft will be flown to Langley Air Force Base (AFB), Va.
Two further aircraft, 4182 and 4183, have been completed, but the company and DCMA can't do required flight testing on those jets, Stinn said. The aircraft are being stored in a near-flight-ready status, she said.
Aircraft "4182 and 4183 were scheduled to deliver in July, but they're not in a position to do any sort of test flights, so we can't deliver," Stinn said. "Maybe early August, but we don't have a definitive date."
Aircraft 4182 and onwards, which have not undergone any of their acceptance flights, have yet to receive their final stealth coatings. The coatings are applied only after a number of flight tests have been completed, and as a result, a backlog is slowly building up.
Before the stealth coatings are applied, the aircraft fly coated only with a primer.
The Raptors have been "stood down" since May 3, according to Air Force spokeswoman Capt. Jennifer Ferrau, due to a suspected problem with the aircraft's oxygen generator.
According to one Air Force document, after reviewing work on a study of the F-22 On-Board Oxygen Generation System (OBOGS), the chief of Air Combat Command, Gen. William Fraser, instituted a temporary flight restriction for the F-22 and directed a Class E Safety Investigation.
The investigation, which began in January, includes the OBOGS installed in the A-10, F-15E, F-16, F-22, F-35 and T-6 aircraft. Fraser appointed Maj. Gen. Steve Hoog, commander of Ninth Air Force, as the investigating officer.
The flight restriction applies to all F-22 crews, but test pilots at Edwards AFB, Calif., are operating under a flight waiver that allows them to fly certain test sorties. Air Force officials at Edwards could not immediately say what kind of test sorties those aircraft are flying.
The grounding is hurting the readiness of operational F-22 pilots, who cannot maintain their currency on the twin-engine jet. The Air Force is using simulators to ease the problem as much as it can.
"Pilots and ground crew continue to train in simulators and perform ground tasks to stay as proficient as possible. Once the aircraft are cleared to fly again, there will be a period where the pilots will need in-flight training to become fully proficient on the aspects of flying that simulators cannot replicate," Ferrau said. "Some live flight is required for high-G maneuvering flight, a true outside visual, and in-flight decision-making in a dynamic environment where simulators are lacking."

Oxygen Issue Keeps U.S. F-22 Fleet Grounded

WASHINGTON - The U.S. Air Force has grounded its entire fleet of F-22 fighters after problems emerged with the plane's oxygen supply, officials said June 24.
The radar-evading F-22 Raptors have been barred from flying since May 3 and Air Force officials could not say when the planes would return to the air.

"The safety of our airmen is paramount and we will take the necessary time to ensure we perform a thorough investigation," spokeswoman Capt. Jennifer Ferrau told Agence France-Presse.
The Air Force was probing possible breakdowns in the oxygen supply system for the plane after several pilots reported problems, according to the journal Flight Global.
In one case, an F-22 scraped treetops before landing, and the pilot could not remember the incident, indicating a possible symptom of hypoxia from a lack of air, the magazine reported.
Ferrau said it was too soon to say for certain that the technical problem was related to an onboard oxygen generating system, known as OBOGS.
"We are still working to identify the exact nature of the problem," she said. "It is premature to definitively link the current issues to the OBOGS system."
Since January, F-22 pilots have been barred from flying above 25,000 feet, following the crash of a Raptor jet in Alaska during a training flight.
Grounding an entire fleet of aircraft is a rare step, officials said.
In November 2007, the Air Force grounded all F-15 fighters after one of the planes broke apart in flight and crashed.
The planes were not allowed back in the air until March 2008, said Maj. Chad Steffey.
The Air Force has more than 160 F-22 Raptors in its fleet and plans to build a total of 187.
The planes have not been used in the NATO-led air campaign in Libya or the wars in Afghanistan and Iraq.

Western Jetmakers Vie For Asian Contracts

TAIPEI - As Western defense budgets crash, East Asian democracies could spend $23 billion within the decade on new fighter aircraft and upgrades, providing lucrative markets for European and U.S. aerospace and defense companies.

Japan released a request for proposals (RfP) in April for 40 fighters for its F-X program. The Boeing F/A-18E/F Super Hornet, Lockheed Martin F-35 Joint Strike Fighter (JSF) and Eurofighter Typhoon are fighting over the $4 billion deal. Bids are due in August with a contract award by the end of the year. The F-X will replace the Mitsubishi F-4EJ Kai Phantoms due for retirement in 2015.

South Korea is expected to issue an RfP in January for its F-X Phase 3 program. While 60 aircraft likely will be involved, it may come in two tranches, with the first being 40. The Boeing F-15, Typhoon and F-35 are already positioning themselves for the $9 billion deal. The FX Phase 3 will replace aging F-4 Phantom and F-5 Tiger fighters. The RfP is expected for release in January.

Taiwan is an exception. Due to Chinese pressure, the U.S. ignored a 2006 request for 66 F-16C/D Block 50/52 fighters for $5.5 billion. Taiwan also awaits a reply to a $4.5 billion request for an upgrade package for older F-16A/B Block 20 fighters in 2009.

With Western defense budgets under review and increasing pressure to pursue new market opportunities, European and U.S. combat aircraft manufacturers are "vigorously" engaging the East Asian fighter market, said Doug Barrie, senior fellow for military aerospace, U.K.-based International Institute for Strategic Studies.

"While Japan and South Korea have traditionally been U.S. combat aircraft customers, the present round of acquisition programs offers Europe an opportunity to break into the market," Barrie said.

European companies face an "uphill battle" to wrestle control of the fighter market from the U.S., which has "locked in markets" for fighter sales to the region for decades, said Richard Bitzinger, a defense industry analyst at the Institute of Defence and Strategic Studies, S. Rajaratnam School of International Studies, Singapore.

"The big question will be if the Europeans can break into this market," Bitzinger said. If not, there is future potential for European aerospace companies to participate in indigenous fifth-generation fighter programs in Japan and South Korea, but in terms of new fighter sales, "these countries are still owned by the USA," Bitzinger said.

Barrie said the Typhoon had its best shot at winning in South Korea, despite the fact Boeing won both F-X Phase 1 and 2 with 60 F-15K Slam Eagle fighters. Boeing might propose the stealthy F-15 Silent Eagle in an attempt to edge the Typhoon out of the competition, he said.

In Japan and South Korea, there is a major effort by the competitors to provide local production opportunities.

"The fighter choice in both countries will send a political signal as to the extent to which, if any, South Korea or Japan wants to begin to build a substantial defense-industrial relationship with their respective relationships with Washington," Barrie said.

Japan's F-X program experienced delays over an intense Japanese lobbying effort begun in 2007 to force Washington to release exports of the F-22 Raptor, but the U.S. Congress blocked the effort. After the F-22 rejection, Tokyo set its sights on the F-35, only to see the JSF effort dogged by delays and cost overruns, which postponed the F-X RfP last year.

Tokyo highlighted its interest in stealth by pursuing an indigenous fifth-generation fighter program. Now, Japan is "using their own fifth-generation fighter [TFX] as a bargaining chip" in the competition, but it is still in the research-and-development stage and "hideously expensive," Barrie said.

Japan is desperate to secure local manufacturing options for the F-X, but it is prohibitively expensive for only 40 aircraft. Manufacturing costs could be driven down by the procurement of more fighters to replace F-15Js, increasing the number of F-X fighters to more than 100 and lowering manufacturing costs.

Unless the F-X fighters are produced in Japan, the local fighter manufacturing industry faces dire straits. Japan's only remaining fighter production line, the Mitsubishi F-2, will end in September.

There are also budget concerns after Japan's devastating triple disaster - earthquake, tsunami and a nuclear power plant crisis - and many wonder how the estimated $300 billion price tag for the catastrophe will affect the F-X budget.

Cost issues could push Japan to select the Super Hornet or the Typhoon. Eurofighter officials have been promoting the Typhoon as a flexible, inexpensive alternative to the F/A-18 and F-35. A European industry source in Tokyo said technical restrictions hamper F-35 exports, while Eurofighter has "no black box policy," which means wider options for Japanese industry participation.

Yet the Japan-U.S. military alliance and pressure to procure a U.S. fighter may keep Tokyo from picking a European fighter.

Taiwan's request for new F-16C/Ds is seen as a follow-on request for an earlier procurement of F-16A/Bs in the 1990s. Despite Beijing protests, the U.S. Congress recently called for the White House to release new fighters and upgrade packages, including a request for a follow-on F-16 trainer program for Taiwan's 21st Tactical Fighter Squadron based at Luke Air Force Base, Ariz. In dollar amounts alone, as the U.S. economy declines, increased pressure on the White House to release the F-16s might be too great to withstand.

"In the case of Taiwan, irrespective of posturing on the part of Beijing, the delivery of F-16 Block 52s should proceed," Barrie said.

Taiwan bought $16.5 billion worth of U.S.­built arms and equipment from 2007 to 2010. Sales included 12 P-3C Orion Maritime Patrol Aircraft, 30 AH-64D Apache Longbow attack helicopters and 60 UH-60M Black Hawk utility helicopters. Taiwan has requirements for signal intelligence aircraft, attack jet trainers, basic aircraft trainers and UAVs.

Chinese Avionics Advances Ripple Throughout Asia

ISLAMABAD - China's avionics industry is closing the gap with other avionics producers, with benefits flowing to Pakistan and new challenges emerging for the U.S.

Chinese aircraft are helping Pakistan maintain conventional deterrence toward India as New Delhi pursues cutting-edge technology to revamp its airpower. As a result, said Usman Shabbir, of the Pakistan Military Consortium think tank, the new "JF-17 Block II [combat aircraft] may see a Chinese AESA [active electronically scanned array] radar along with an IRST [infrared search and track] sensor, and an even better ECM [electronic countermeasures] suite."

Wider advances by China's aviation industry would result in "greater use of composites to reduce the overall airframe weight" for the JF-17 Block II, and also a thrust vectoring control engine; though Shabbir conceded the latter "has never been officially confirmed."

Analyst Kaiser Tufail said an AESA radar is "the way to go," and that "all future [radar] acquisitions or retrofits would be AESA, whether mechanically scanned or phased-array type."

Tufail said the current JF-17 radar, a variant of which is fitted to the Chinese Chengdu J-10 combat jet, is an interim solution "because the [Pakistan Air Force] had been unable to find a radar vendor who could sell cutting-edge technology at an affordable price."

Tufail said Pakistan's acquisition of advanced Chinese avionics should not be seen through the prism of Indian programs, such as the Medium Multirole Combat Aircraft program. Rather, he said, it should be seen as Pakistan's effort to keep pace with modern weaponry.

And China benefits from its collaboration with Pakistan.

"Traditionally, the Chinese aviation industry has found an excellent test bed in the PAF, and their products have been, and can be, proven in ways that are not possible with [China's Air Force], due to limitations of comparative analysis in truly operational scenarios and with respect to Western equipment that PAF operates," he said.

As a result, a "Chinese AESA radar would, therefore, be a synergetic success in partnership with Pakistan," he said.

However, it is unknown whether the new JF-17 Block II radars are variants of those fitted to the improved J-10B. If that is the case, analyst and Chinese specialist Andrei Chang said the new radar is unlikely to be an AESA type.

"The phased-array radar testing on the J-10B is a passive model," he said.

Chang said he does not think the Chinese have developed "a useful AESA radar for the JF-17 and J-10B," but they could in the future.

"I know they are researching AESA radars, but it takes time," he said.

China's technological advances give potential adversaries cause for concern, Tufail said.

"As in many other fields like space and information technology, China is making a mark in major ways which impacts geostrategic and security issues," he said. "Technological developments like AESA radars would, thus, certainly have a bearing on the comfort levels of countries that have an adversarial relationship with China."

The potential threat posed by Chinese advances in avionics is an issue Carlo Kopp of the Air Power Australia think tank has tried to raise.

"Chinese technology is a mix of reverse-engineered Western and Russian designs, and some often very good indigenous ideas," he said. The danger this poses is clear.

"As the Chinese advance and proliferate these products, they are increasingly narrowing the range of environments in which Western air forces and navies can operate," Kopp said.

CHINESE DEFENSES

"Today, only the U.S. F-22A [stealth fighter] and B-2A [stealth bomber] can penetrate Chinese airspace with impunity," he said. "All other Western designs, including the intended F-35 [Joint Strike Fighter] and existing F/A-18E, would suffer prohibitive loss rates" to surface-to-air missiles, he said.

Kopp's opinion of the F-35 is perhaps surprising, but he said he believes China's investment in more maneuverable aircraft will expose severe weaknesses.

"The notion that having a good AESA [radar] can overcome kinematic performance limitations in a design is predicated on the idea that your missiles are 100 percent effective in long-range combat," he said. "The evidence shows otherwise for the AIM-120 AMRAAM."

The approach that says "let the missiles do the turning," rather than the aircraft, "is a mantra in the F-35 and F/A-18 camps," Kopp said. "Unfortunately, it is wishful thinking by folks promoting obsolete designs. The mathematics and physics of aerial combat do not support this proposition."

Therefore, the strategic impact of China's advances will be substantial and exacerbated by poor long-term decision-making by the U.S., Kopp said.

"As China wholly recapitalizes its fleets, and exports these products, there will be an inevitable strategic impact, as the U.S. has been reluctant to export the F-22, has chopped F-22 production funds, and has no new products in the pipeline capable of robustly surviving against top-end Chinese products in combat," he said.

Kopp also blames the reluctance by Washington to share high-technology weaponry with allies that could check China's advance.

He singles out Defense Secretary Robert Gates for making decisions that will produce "a dangerous long-term strategic environment in Asia as China introduces and proliferates advanced technology, and the U.S. chooses for ideological reasons to no longer invest in advanced air power."

F-35 Engine Maker to Slowly Lower Cost

Engine maker Pratt & Whitney says it is incrementally lowering the price of its F-35 power plant and could possibly drop the cost even more as the Pentagon begins negotiating for the latest batch of fighter jets.

Engine maker Pratt & Whitney says it will lower the price of the F-35 power plant. (CHERIE CULLEN / U.S. DEPARTMENT OF DEFENSE)

"We have activities planned and in place to bring the cost down in [low-rate initial production] 5," Bennett Croswell, president of Pratt & Whitney military engines, said during a June 6 briefing in Washington.

Negotiations for the fifth batch of Joint Strike Fighters between the Pentagon and F-35 prime contractor Lockheed Martin just commenced.
The company has a goal to reduce the F135 cost to the price of the F-22A power plant, the F119, by the 250th engine. Pratt has developed a metric of shrinking the cost of the F135 incrementally to reach that goal. Company officials declined to cite those prices, which they consider proprietary.
Pratt officials said they were able to beat their projected pricing targets during negotiations for the fourth batch of F-35 production aircraft last year.
"We're constantly looking at ways to do even better than what that plan is," Croswell said.
At the same time, the company has validated an improvement to increase the thrust of the Marine Corps version of the F-35, which can land vertically.
Through a software change "that reduces the variability of the lift system components," the company is able to add about 100 pounds of thrust, according to Edward O'Donnell, director of F135 and F119 business development. The company is also working to lighten the engine about 100 pounds.
Validating these improvements before the end of the fiscal year in September could become critical for Pratt if language in the House version of the 2012 defense authorization bill become law. The language would require the Pentagon to restart the canceled F-35 alternate engine program - run jointly by General Electric and Rolls-Royce - should a future requirement for more thrust crop up.
"Right now, the F135 meets all of our thrust specification requirements," O'Donnell said. "As we look at the program going forward, there does not appear to be any need to increase the thrust of the engine."
Addressing the House language, O'Donnell said: "It's unfortunate that language in Congress would tie our hands or prevent us from being able to work on the engine should that requirement come forward."