In its 20th flight, the first F-35 Lightning II aircraft was successfully tested for engine performance and handling qualities at altitudes as high as 20,000 ft (6,096m) as its pilots and ground crew prepare for air refueling trials in the coming weeks. At the same time, a dedicated test-bed Boeing 737 aircraft began final checkout flights for airborne testing of the Lightning II's communication/navigation/identification system, initiating a test program that will validate the complete F-35 avionics package.
"We are poised for a long run of testing on both of these aircraft,"says Dan Crowley, Lockheed Martin (Ft. Worth, Texas) executive vice president and F-35 program general manager. "At the same time, we are putting the finishing touches on our first short takeoff/vertical landing F-35 aircraft, which will roll out of the factory this month and begin flight testing in the spring. By the end of 2008, we expect to have at least three F-35s in the air and numerous aircraft on the assembly line.â€
The Lightning II's flight began when chief test pilot Jon Beesley executed a military-power (full power without afterburner) takeoff, ran the engine at various power settings, checked flying qualities at 6,000 ft, 17,500 ft and 20,000 ft (1,829m, 5,334m, 6,096m) and performed a fuel-dump test at 250 knots. Beesley reported that the tests were successful and the jet was a pleasure to fly.
The Cooperative Avionics Test Bed 737, or CATBird, took off on a two-hour functional check flight, one of its final sorties before F-35 mission systems testing begins. CATBird is a highly modified airliner designed to test, integrate and validate the full F-35 mission systems suite in an airborne environment before the system ever flies in an F-35 aircraft. Successive CATBird flights will add elements of the F-35 mission systems suite until the entire Lightning II avionics package is onboard. The mission systems will be fully integrated and operating as they would on an actual F-35 aircraft - a first for a fighter test program. The F-35 mission systems suite is entirely internal to the aircraft, with no external pods or sensors, a configuration that will preserve the Lightning II's stealth profile. The first mission systems-equipped F-35 will fly in 2009.