One of the stunning admissions that came out of the US AirForce Scientific Advisory Board F-22 briefing on 29 March was that the servicehad let its aerospace physiology competency atrophy.
Read the full story here: http://www.flightglobal.com/news/articles/usaf-to-rebuild-its-aerospace-physiology-expertise-370521/
They also haven’t figured out what’s causing the F-22′s problems:
The Raptor flies well above the 50,000ft ceiling (by USAFregs) of other fighters like the F-15 and F-16, but unlike pilots flying thehigh-flying U-2, F-22 pilots don’t wear a pressure suit. The USAF issues awaiver to pilots, which allows them to fly up to 60,000ft while wearing theCombat Edge g-suit (60,000ft is the limit due to the Armstrong Line-which isfound at an altitude of between 62000ft and 63000ft, where the outside airpressure is so low that water will start to boil at 37°C or 98.6°F) The CombatEdge is ostensibly supposed to act as a partial pressure suit.
However, after years (decades) of enduring spells of decompressionsickness (from wearing an actual pressure suit, but astonishingly enough, nothaving it inflated) from exposure to cabin altitudes of around 29,000 ft, U-2crews are getting some relief.
The USAF is modifying the U-2 to allow for a lower cabinaltitude of between 15,000ft and 16,000ft. It’s hoped that will banishdecompression sickness from the U-2 community–which happens even though crewsundergo elaborate pre-breathing (with pure oxygen and cardio) procedures hoursahead of a flight.
Raptor pilots, however, don’t have any of those proceduresor a pressure suit… but are exposed to nearly the same kinds of cabinaltitudes. Perhaps the U-2community might have some insight into the Raptor community’s woes?