The U.S. Air Force plans to examine how to resolve parts obsolescence issues for the on-board oxygen generation systems (OBOGS) for the Boeing [BA] B-1B and Northrop Grumman [NOC] B-2 bombers.

Honeywell‘s [HON] Yeovil, England subsidiary is the prime contractor for the systems. In addition, Honeywell has built other life support systems for military aircraft, including the U.S. Navy’s T-45 trainer by Boeing and the Air Force’s F-22 fighter by Lockheed Martin [LMT].

The Air Force Sustainment Center at Tinker AFB, Okla. has identified seven B-1 and B-2 parts as having obsolescence issues: the B-1 Molecular Sieve Oxygen Generated System Oxygen Concentrator, the B-1 Release Valve, the B-1 Regulator, the B-1 Purge Valve, the B-2 Oxygen Generation and Distribution System Oxygen Concentrator, the B-2 Release Valve and the B-2 Regulator.

“All are critical components of the breathing oxygen life support systems on the respective aircraft,” per a May 3rd Air Force presolicitation notice.

“Phase I will consist of performing a comprehensive analysis of the existing technical data, materials/processes, special tooling/test equipment, and sub-tier suppliers to identify/document the specific areas of obsolescence and provide a resolution plan which will be used to scope the following phases of the effort,” the presolicitation notice said. “A report detailing the findings and proposed resolution plan will be the primary contract deliverable at the end of Phase I.”

The latter is to last 18 months, per the notice.

Aircraft cabins require additional OBOGS oxygen at altitudes above 10,000 feet. Hypoxia has been an issue for military pilots in the last decade, first with the F-22 in 2011.

The National Commission on Military Aviation Safety (NCMAS) said that it received reports of pilot hypoxia on a number of other aircraft, including Air Force F-15s, F-16s, and A-10s; the Navy T-45 trainers and F/A-18s by Boeing, and the F-35 by Lockheed Martin (Defense Daily, December 3, 2020).

NCMAS said that the military services have been able to research and explain the majority of physiological events (PEs) that caused military aviation accidents between 2013 and 2018.

The commission said that it discussed the PEs with a number of organizations and personnel, including the Air Force 711th Human Performance Wing at Wright Patterson AFB, Ohio, Navy and Air Force medical researchers and NASA.

Retired Army Gen. Richard Cody, the service’s former vice chief of staff and the chairman of NCMAS, said last year that “we need to treat the human in these high performance aircraft the way we treat the aircraft” and that the commission and medical researchers have advocated on-board sensing systems to evaluate and remedy physiological stresses on aircrews, similar to the strain gauges and Health and Usage Monitoring Systems that monitor equipment on the aircraft.