Aircraft

Lockheed Martin has launched the last phase of check-out testing for the Cooperative Avionics Test Bed (CATBird), a highly modified Boeing 737-300 carrying the mission systems suite of the F-35 Joint Strike Fighter.

Performed on 25 November, the CATBird's 40th flight launched in-flight integration and verification of the F-35's systems, including its Northrop Grumman APG-81 radar, electro-optical tactical targeting system, distributed aperture system, communications-navigation-identification system and electronic warfare suite.

Next year, Lockheed will start the first of 180 flights needed to complete airborne testing of the F-35's on-board systems, which account for about 7 million lines of software code.

The first verification tests have focused on checking the performance of the APG-81. The active electronically scanned array radar transmitted for 23min during the 2.4h sortie, selecting six different tactical control and navigation stations. "The results matched our predictions," says Eric Branyan, Lockheed's vice-president of F-35 air system development.

© Lockheed Martin

The CATBird's significance in the programme grew last year because of the impact of an internal cost overrun. Instead of adding money to the development phase, the JSF Joint Programme Office and Lockheed decided to cut several flight-test aircraft, including two airframes - AF-5 and CV-4 - dedicated to mission systems testing.

The balance of these tests will now be split between the CATBird and BF-4 - the fourth short take-off and vertical landing aircraft to roll off the production line, Lockheed says. This is scheduled to enter flight tests in mid-2009.

Lockheed plans to have rolled out the first seven ground and flight-test aircraft by the end of December. BF-3 is expected to be rolled out on 13 December, followed by AF-1 on 19 December. The AG-1 static airframe is also scheduled for roll-out later this month.

Lockheed is on contract to deliver the next 12 F-35s by the end of 2009, or at a rate of one per month.