"WASHINGTON: The Navy, hasn’t been able to process 25 prospective pilots for each of the last three months as it struggles to find the cause of what may be hypoxia episodes afflicting many T-45 pilots, has not been able to ferret out what is causing them to suffer from headaches and other symptoms.
Vice Adm. Paul Grosklags, the head of Naval Air Systems Command, testified to the Senate Armed Services seapower subcommittee this afternoon that the Navy has analyzed all the systems feeding air to its pilots in T-45s and has “not been able to discover a culprit.” So far 75 pilots have not been able to qualify.
You could see the frustration on the admiral’s face as he spoke. Problems like this can be very difficult to figure out — it took the Air Force several years before it reliably demonstrated it had fixed hypoxia problems with the F-22 — and, as you can see from the chart below, there have been sharp increases in reported incidents since 2014 for the T-45s and all but one of the F-18 models.
Even so, Grosklags told the subcommittee he thought pilots would be back to flight training in “weeks, not months” thanks to an array of prophylactic measures the Navy plans to implement so pilots can identify problems before they become life threatening...."
Navy Can?t Find ?Culprit? Of T-45s Suspected Hypoxia; Mattis Pledges Afghan Strategy « Breaking Defense - Defense industry news, analysis and commentary