A Goldman Sachs analyst said Boeing may face another delay in rolling out the new 787 Dreamliner, Bloomberg News reported.

Richard Safran wrote to his clients that the deliveries may start in the third quarter of 2009.

He wrote that the plane's first power-up may be delayed until the end of June, rather that late March, Bloomberg reported.

Boeing Co. spokeswoman Yvonne Leach said it's in the middle of reassessing the schedule for the new 787 and won't announce the results until the end of the month.

VIDEO: 787 Delay Would Be Plane's Fourth

Leach told KIRO 7, “This is a complex process that involves working with our supply chain to assess the impact of this schedule change on our flight test program and first deliveries.”

The company started the assessment in January when it announced a delay in assembling the wide-bodied jet.

Goldman Sachs analyst Safran says Boeing underestimated the amount of work required on the 787 and that changes to the airplane have caused delays in completing the wiring of the aircraft.

The 787 is Boeing's first newly designed jet since airlines started flying the 777 in 1995. It will be the world's first large commercial airplane made mostly of carbon-fiber composites, which are lighter, more durable and less prone to corrosion than more traditional aluminum. Boeing says it will be cheaper to maintain and offer better fuel efficiency and more passenger comforts than comparable planes flying today.