Lockheed Martin is preparing to rush a sixth F/A-22 Raptor to a US Air Force operational test squadron that is voicing concerns about sortie generation rates less than two months before the next critical phase of test flights begin.

Brig Gen Rick Lewis, F/A-22 programme executive officer, favours adding an aircraft to the five in the test fleet at Edwards AFB, California. The availability of a second spare airframe should ensure operational testers can conduct realistic four-ship evaluations.

"We can probably generate four-ship sorties with a five-ship fleet, but for extra insurance maybe we should get a second spare in the mix," says Lockheed Martin. "[Lewis] thinks sortie generation rate is going to be an issue. To ensure that it won't be an issue, he's saying we may need that other jet."

Maj Gen Doug Pearson, commander of the Air Force Flight Training Center, has voiced his disappointment with the Raptor's high maintenance needs and low sortie generation rates. His unit is now flying the F/A-22 on a preliminary round of two-ship operational tests.

Lockheed Martin describes the concerns as normal during any hand-off of a new aircraft to an operator, and says the F/A-22's reliability should improve as air force maintenance crews become more familiar with it.

The US Defense Acquisition Board, which governs all major spending programmes, is expected to review the F/A-22's progress on 22 March. Separately, air force planners are reshaping the F/A-22 spiral development roadmap with the aim of speeding the introduction of ground attack capabilities, like radio transmitters, satellite communications and the small- diameter bomb.

Air Combat Command "is having meetings to say: 'all right, which one of these assets can we move over to the left and get on to the aircraft sooner?'," says Keith Bilyeu, a Lockheed Martin business development director, adding: "What we thought was in concrete a month ago is being looked at again."

Source: Flight International