Boeing has estimated a 15-month delay in 787 deliveries but some customers are facing delays of two years or more, The Seattle Times reported.

Launch customer ANA is scheduled to receive its first aircraft in the third quarter of 2009 instead of this month, but the manufacturer's ambitious ramp-up plans also have slipped and full production of 10 planes per month will not be reached until 2012, two years later than planned.

It has reported that ILFC, the largest 787 customer, has been advised that it will have to wait an average of 27 months for its aircraft, citing a May 8 regulatory filing from ILFC parent AIG.

Boeing spokesperson Yvonne Leach confirmed that average delay of first delivery for all 58 Dreamliner customers is working out to about 20 months.

Customers obviously are inconvenienced, although many who have spoken now feel there is definition to the schedule and are hopeful that the company will improve upon it.

One executive who declined to be named said the new schedule is "more conservative this time, with upside" regarding deliveries.