This appearance marked the end of almost two years of factory seclusion for the prototype after the ceremonial roll-out on 8 July 2007 that preceded the programme's rash of part shortages, production problems and design changes.

The confirmation from Boeing occurs after Bernstein Research recently released a report estimating that early production 787s could be delivered as much as 8% overweight resulting in a range shortfall of 10-15%, putting the 787's range at 12,800km (6,900nm), well below the advertised ranges of 14,200-15,200km.

EVERETT, Wash., June 23 /PRNewswire-FirstCall/ -- Boeing (NYSE: BA) today announced that first flight of the 787 Dreamliner will be postponed due to a need to reinforce an area within the side-of-body section of the aircraft.

The need was identified during the recent regularly scheduled tests on the full-scale static test airplane. Preliminary analysis indicated that flight test could proceed this month as planned. However, after further testing and consideration of possible modified flight test plans, the decision was made late last week that first flight should instead be postponed until productive flight testing could occur.

First flight and first delivery will be rescheduled following the final determination of the required modification and testing plan. It will be several weeks before the new schedule is available. The 787 team will continue with other aspects of testing on Airplane #1, including final gauntlet testing and low-speed taxiing. Work will also continue on the other five flight test aircraft and the subsequent aircraft in the production system.