Capt. Jeff Haney was flying over Alaska in late 2010 when an engine bleed-air malfunction on his F-22 Raptor caused the control system to shut off oxygen flow to his mask.
For the next 30 sec., Haney struggled to activate his emergency backup oxygen supply, seeming not to notice as his aircraft rolled into a steep dive. At the last second, Haney tried to pull up, but it was too late. He struck the ground going faster than the speed of sound and died on impact.
This is what U.S. Air Force accident investigators believe occurred on the night of Nov. 16, 2010. Haney, a promising young pilot assigned to the 525th Fighter Squadron at Joint Base Elmendorf-Richardson, Alaska, had just completed a routine training flight. Many aspects of the crash remain unexplained, including the cause of the malfunction that led Haney’s oxygen system to shut down and the reason he did not pull up sooner.
Almost seven years later, the Air Force and U.S. Navy are struggling to understand why pilots across the fleet seem to be losing oxygen during flight in increasing numbers. A recent spike in hypoxia-like cockpit incidents, in which pilots report shortness of breath, disorientation, and tingling fingers, caused the Navy to ground the T-45 Goshawk training fleet in April, and the Air Force temporarily suspended F-35A flight operations at Luke AFB, Arizona, in June due to similar problems. Meanwhile, these so-called physiological episodes (PEs) are also on the rise in the Navy’s F/A-18 fleet.
The issue is a complex one that the services have so far been unable to resolve. It is not even clear that what the pilots are experiencing is actually hypoxia—defined as an insufficient supply of oxygen—or something else that causes similar symptoms, such as a change in cabin pressure, contaminated air, or even too much oxygen. Investigators are looking into a range of possible root causes, including a problem with the Onboard Oxygen Generation System (Obogs). (end of excerpt)
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