EVERETT, Wash. -- Crews powered-on the first 787 Wednesday at the Everett plant, after months of delays to Boeing’s 787 Dreamliner.

“We’re pleased the process has begun, and we are confident we’ll meet the milestone in June,” said Boeing.

Boeing said the power-on process lasts between 10 days and two weeks. They hope to have it completed by the end of the month.

The power-on testing was originally schedule to be in late March.

In a Boeing 787 program schedule released in April, the company said it hopes to have the first flight in the fourth quarter of 2008, with the first delivery planned for the third quarter of 2009.

Three Dreamliners are in the process of being assembled, with the sections of the fourth plane arriving this month.

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.