Boeing has said that it now expects delivery of the first 787 in the middle of first-quarter 2011.
The delivery date revision follows an assessment of the availability of an engine needed for the final phases of flight test this autumn.
While Boeing works closely with Rolls-Royce to expedite engine availability, flight testing across the test fleet continues as planned.
Boeing said last month that the cumulative impact of a series of issues, including supplier workmanship issues related to the horizontal stabiliser and instrumentation delays, could push first delivery of the 787 a few weeks into 2011.
The delay in engine availability has extended that estimate to mid-first-quarter 2011.
The schedule revision will not affect the company’s financial guidance.