US Air Force secretary Jim Roche says the service intends to convert some orders for the conventional Lockheed Martin F-35A Joint Strike Fighter (JSF) to the F-35B short take-off and vertical landing (STOVL) variant.

The proposal unveiled at the Air Warfare Symposium in Orlando on 12 February provides a much-needed boost to the F-35B variant ordered by the US Marine Corps and UK Royal Navy and signals a strong new strategic emphasis by the USAF on the close air support (CAS) mission.

Roche's expanded vision for CAS calls for the revitalisation of the Fairchild A-10 fleet, including a re-engining programme. Lockheed Martin's A-10 sustainment programme has identified candidates from three engine manufacturers for replacing the General Electric TF34. A Lockheed Martin source says that the early favourite is an updated CF34 powerplant called the TF34-100B. A certain number of A-10s would be retired as the upgraded aircraft are delivered to the fleet fitted with new engines, precision targeting systems and refurbished wings.

Meanwhile, USAF Air Combat Command is studying how to choose the right number of F-35Bs to carve out of the service's requirement for 1,763 F-35As, says Roche.

The proposal comes as the programme faces a weight growth problem that has caused a $5 billion, one-year delay in the development schedule, and has prompted concerns about the variant's chances of survival.

Lockheed Martin now says the performance problem is confined to the short take-off and vertical landing mode of the F-35B, while level flight performance is unaffected. A plan for resolving the weight problems is expected to be in place when the JSF programme office completes the F-35A critical design review in April. It is understood that one option being considered would reshuffle the test flight schedule so the simpler F-35A precedes the F-35B.

Air Force chief of staff Gen John Jumper also elaborated on the air force's emerging new long-range strike plan, citing the possibility of equipping two-seat Lockheed Martin/Boeing FB-22s with 120 small-diameter bombs.

Source: Flight International