The first flight of the US Navy Boeing P-8A Poseidon maritime patrol aircraft on 25 April cleared the way for the programme to focus on integrating and testing the mission system for the second flight-test aircraft.
The 3h 41min first flight saw the 737-800-derived T-1 test aircraft lift off from Renton Field at 10:30 and fly up to 25,000ft (7,620m), says Bob Feldmann, Boeing vice-president and programme manager for the P-8A.
Until now, the programme has had to overcome structural design challenges, with the P-8A's basic structure being 75% unique compared with the 737-800, says Feldmann. Those challenges included integrating a weapons bay in the keel of the airframe.
Following T-1's first flight, the programme is now working on resolving the "inevitable" software anomalies that appear in such a complex mission system, says Feldmann.
The unpainted green aircraft completed the same test points on first flight as any commercial 737, including airborne systems checks, accelerations and decelerations and shutdowns and restarts of the auxiliary power unit, says Feldmann.
© Larry Trotter/Boeing
Meanwhile, the T-2 test aircraft, which has been painted in US Navy colours, is being prepared for a repositioning flight from Renton to nearby Boeing Field.
While the T-1 is dedicated to airworthiness testing, the T-2 and T-3 flight-test aircraft are assigned to checking out mission systems and weapon systems, respectively.
The P-8A programme will integrate the mission systems, which includes more than 2 million lines of software code, on the T-2 at Boeing Field, said Feldmann.
The USN originally planned to fly T-2 to Patuxent River, Maryland in September to begin mission systems flight testing. But the USN is now in talks with Boeing about extending the Seattle-based test phase for T-2 by several months, says Capt Mike Moran, the USN's programme manager for patrol aircraft and reconnaissance programmes.
The programme hopes the extension will create "some efficiencies" and perhaps shorten the overall flight-test schedule, says Moran.
Moran acknowledges that the mission system is "an issue that we're concerned about, but we've got a good chance to be successful and keep to schedule".
The T-2 is set to complete its first flight with a full mission system in the first quarter of fiscal year 2010, Moran says.