Lockheed Martin has been awarded a $11.9 million contract to supply the US Air Force (USAF) with additional automatic back-up oxygen supply (ABOS) systems for its stealthy F-22 Raptor air superiority fighters.

According to Lockheed, the contract modification covers 70 aircraft kits plus five spare kits. The contract also covers support equipment and ancillary spare parts.

This is the second batch of ABOS kits that the USAF is buying for the Raptor fleet. The service has previously awarded Lockheed a contract to supply 40 ABOS kits along with 10 spares.

The USAF is expected to order a third batch of ABOS kits for its remaining F-22s sometime later.



The air force is equipping its entire fleet of 185 Raptors with the new ABOS as part of a plan to improve the jet's life support systems. The existing back-up oxygen system, which will remain in place, is manually activated-and was recently modified with a more user-friendly handle.

The lack of an ABOS was identified as one of the deficiencies in the F-22's life support systems during an investigation into a series of physiological incidents resembling hypoxia that has plagued the stealthy fifth-generation fighter for the past several years.

Ultimately, the USAF concluded that a faulty valve in the pilots' Combat Edge upper pressure garment and the aircraft's oxygen schedule were causing the problem. The service says it is implementing fixes.

Source: Flight International