Graham Warwick/WASHINGTON DC
Lockheed Martin believes that it can reduce F-22 flight-test delays caused by manufacturing problems to "a few weeks", despite wing deliveries from Boeing being several months behind schedule.
Problems with the large titanium "side-of-body" castings which attach the wing to the fuselage have been solved, says outgoing programme general manager Tom Burbage.
All castings for the development F-22s have now been delivered, he says, but the problems have delayed delivery of the wings by three to six months.
Lockheed Martin has pressed ahead with final assembly, performing work out of sequence in an effort to catch up.
Wings have now been attached to the third flight-test aircraft, 4003, allowing power-on testing to begin on 1 April.
"Boeing will be three to six months late delivering wings, but we will be only three to six weeks late delivering aircraft," believes Burbage. "We should be back on track by aircraft 7 - for sure by 8 and 9," he says.
Aircraft 4003 is scheduled to fly in late November and will join the first two F-22s at the Edwards AFB, California, flight-test centre, where they have so far accumulated over 200h flying. The first avionics-test aircraft, 4004, is scheduled to fly in February 2000.
Software development is ahead of schedule, says Burbage. Block 1.1 software, which will allow the avionics in 4004 to be turned on during final assembly, will be delivered in June. Block 2, which will provide sensor fusion for the first time, will be released to Boeing's 757 flying testbed in July.
Block 3S is on schedule for a critical design review late this year. Because of delays with the communication/navigation/identification system, 3S is an interim block that will enable flight testing of sensor-fused avionics to begin in the F-22 earlier in the programme. "We need to fly fused data early, so we actually pulled technical capability ahead," Burbage says.
Source: Flight International
