Boeing hopes this week to know when it can begin final assembly of the delayed fourth flight-test 787 airframe, as efforts continue to complete ships one and two by the fourth-quarter first-flight target.
Delivery of subassemblies for the fourth flying 787 to the Everett final assembly line was due to be completed last month, to allow work to begin.
However, completion of the centre fuselage subassembly at the Global Aeronautica plant in Charleston, South Carolina has been held up.
This section, which sustained minor damage during production, is still undergoing completion as Boeing tries to implement the series production system to the build process and reduce the travelled work being undertaken in Everett.
"We have to get the production system to work in the way it's designed," says Pat Shanahan, 787 programme vice-president and general manager. "If I don't get it on its learning curve then I can't ramp up production."
Speaking at Farnborough, Shanahan said Boeing hopes to finalise the ship-date for the centre-fuselage to Everett "this week".
Meanwhile, Shanahan says that the effort to get the 787 ready for its much-delayed first flight "feels almost as complicated as putting a man on the moon now".
Assembly of the first two aircraft must be completed ahead of the start of flight testing - Dreamliner one is due to be the first airframe to fly while Dreamliner two must be finished so it can undertake some ground vibration testing to clear the first aircraft for flight.
Shanahan says there is one item giving concern as the completion of aircraft one progresses towards the start of "gauntlet testing".
He adds: "I expect to have all the first aircraft's hardware functionality qualified for the maiden flight by the third week of August, except the brakes. This is not a functionality issue, but rather a certification issue. It's to do with the tracability of the software."
While he confesses that he "doesn't know" when the problem will be resolved, Shanahan is "confident that [brake system supplier] GE will get it done, but right now it seems like an odd thing to be sticking out in the programme".
The next milestone on Dreamliner one will be testing the hydraulics, which is due to start next week "and then we'll start swinging the gear", says Shanahan. "We've got the [Rolls-Royce Trent 1000] engines on the aircraft now, and the [next] equivalent of power-on is running the engines."
The progress of aircraft two has been hampered by completion of the mid-body, which has eaten up some of "the padding in the schedule", says Shanahan.
"At this point it doesn't change flying [airplane one] in the fourth quarter of 2008 or first delivery in the third quarter of 2009, but I'm eating margin I don't want to eat," he says.
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