Carbon monoxide suspected in F-22 grounding

There may be a different angle on the F-22 grounding.

AF Times is reporting that carbon monoxide from the engines may have contaminated the life support system. There has been no official confirmation from the USAF.

The prolonged grounding of the 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.

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.

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