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F-22 Raptors Grounded at Langley Air Force Base

Raptor fleet returns to flight while pilots scratch their heads – but then ...

The U.S. Air Force’s on-again, off-again saga with the grounding of its F-22 Raptor superfighter fleet took a new twist on October 21 when Raptors at one base were grounded – again.

Raptors of the 1st Fighter Wing at Langley Air Force Base, Va., are idle again after a pilot experienced oxygen loss in mid-flight. “Part of our protocol is to allow units to pause operations whenever they need to analyze information collected from flight operations to ensure safety,” the Air Force said in a statement issued at the Pentagon. “That is what is happening at Langley at the moment, and we support that decision.”

Raptors had returned to flight in September after a four-month grounding while a scientific advisory board conducted a study of the F-22 and other aircraft using Onboard Oxygen Generation Systems (OBOGS).  Problems with the oxygen system of the costly, diamond-winged superfighter were initially thought to be responsible for a fatal crash and possibly the cause of toxins found in the blood of some of the Air Force’s 400 Raptor pilots – all of whom lost their cockpit currency during of the grounding and had to be re-qualified. Twelve separate reports of pilots experiencing symptoms of hypoxia had also been a factor in the grounding of the Raptors.

Despite concerns that pilots were passing out due to a lack of oxygen, Air Force officials authorized the planes to resume flying, but said that they had not identified the problem vexing the F-22 fleet. This prompted Mark Thompson of Time magazine to write that it was “amazing” that “the problem was serious enough to ground the planes but apparently not serious enough to fix.”

The new decision to ground the fighters at one base only came after Raptor squadrons installed an extra air filter on the aircraft. The function of the air filter is not clear and the Langley grounding suggests it hasn’t solved the problem.

Between May and October, the Air Force’s 158 Raptors (out of a planned purchase of 187) were parked indoors draped in protective materials. But after ordering the fleet-wide stand-down, officials decided that OBOGS was not a factor in the Nov. 16, 2010 crash that killed F-22 pilot Capt. Jeffrey “Bong” Haney, 31. Haney belonged to the 525th Fighter Squadron “Bulldogs” at Joint Base Elmendorf-Richardson, Alaska. Haney’s aircraft went down 100 miles northeast of Anchorage. Now, they’ve concluded, Haney died in aircraft 06-4125 because of a malfunction with the aircraft engines’ bleed air system that caused several other systems aboard the Raptor to shut down abruptly.

Still, OBOGS has also been linked to problems aboard Navy and Marine F/A-18C/D Hornets, which use a system developed by Cobham. The F-22 employs a Honeywell system. An OBOGS uses engine bleed air, separating out nitrogen and other components through a molecular sieve and providing a continuous supply of nearly pure breathing oxygen. A solid-state oxygen monitor ensures that the oxygen concentration meets requirements.

After the Haney crash, medical tests found toxins in the bloodstreams of Raptor pilots at several bases.

When the F-35 Lightning II Joint Strike Fighter was grounded briefly and temporarily in August after an electrical failure, the Pentagon was taking hits from critics who questioned the cost and capabilities of the latest generation of jet fighters. Some ask why the F-22 has never been in combat. Advocates respond that the F-22 and F-35 are needed for “peer” warfare against a modern nation-state with high-tech weaponry. They never fully explained why F-22s were returned to the air when the cause for grounding them remained undiscovered and haven’t provided a full explanation of the latest grounding, either.

Update: F-22 Raptors of the 1st Fighter Wing resumed flight operations on Oct. 25, 2011. The 3rd Wing, at Joint Base Elmendorf-Richardson in Alaska, returned its Raptors to flight status on Monday, Oct. 24. F-22s based at Tyndall AFB, Fla., Nellis AFB, Nev., Holloman AFB, N.M., and at Joint Base Pearl Harbor-Hickam, Hawaii, flew as normal throughout the grounding of 1st and 3rd Wing aircraft.


Robert F. Dorr is an author, U.S. Air Force veteran, and retired American diplomat who...