USAF aircraft checks related to the grounding of its most-advanced air superiority fighter remain ongoing, according to new comments made by officials on 25 July 2011.
In May 2011, all USAF F-22 Raptor flights were banned in connection with issues concerning the type's oxygen production systems.
Immediately afterwards, the USAF Scientific Advisory Board was tasked with undertaking a rapid investigation into not only this aircraft's built-in oxygen generation technology, but that forming part of many other USAF types, too. Combined, these produce quite an extensive list, made up of:
* USAF A-10 Thunderbolt II close air support and ground attack aircraft
* USAF F-16 Fighting Falcon multirole combat aircraft
* USAF F-15E Strike Eagle multirole fighters
* USAF B-1B Lancer strategic bombers
* USAF B-2 Spirit stealth bombers
* USAF CV-22 Osprey tiltrotor aircraft
* USAF T-6 Texan II trainer aircraft
USAF Oxygen System Checks
The USAF oxygen system checks measure also covers F-35 Lightning II Joint Strike Fighters (JSFs), which are not yet in service, but are set to equip the USAF in future years. While no Raptors are flying at present, the officials involved have stressed that no such restrictions have been placed on other, in-service USAF equipment.
"The safety of our aircrews is paramount", Major General Gregory Feest - USAF chief of safety - explained, in a statement. "This review is a prudent step to ensure that all potential technical, causal and contributory factors have been fully considered and that all appropriate steps are being taken to enhance flight safety."
Raptor Oxygen System Investigation
The original Raptor oxygen system investigation itself has now suggested that pilots flying the aircraft, prior to the grounding, had been in contact with toxic materials drawn into their cockpits. Blood tests have revealed the presence of oil fumes, anti-freeze residue and other toxins, although information relating to the identity of those affected has been kept private for the time being.
"There is a lot of nasty stuff getting pumped into the pilots' bloodstream through what they're breathing from that OBOGS [On-Board Oxygen Generation System], the Air Force Times quoted one source as having explained. "How bad it is, what type it is, exactly how much of it, how long - all these things have not been answered."
Armed Forces International will present further coverage of this situation in future News Items.