After two years of generating crisis headlines, Boeing 787 Dreamliners are finally rolling off the Everett, Washington, assembly line.

The next-generation composite jets are finished and ready to fly—but for a structural weakness where the wings join the body. Because of the flaw, the planes can’t be delivered to frustrated customers until late 2010 at the earliest.

So far, the company has churned out seven flyable planes and is ramping up to produce 10 a month—so many that the new planes are starting to stack up outside the factory, and some may have to be parked in Texas.

But that hasn’t stopped Boeing from pressing hard to get the line rolling, despite the flaw. Doing so represents a key milestone in honing the production process, officials say. The moving line is perhaps the most tangible positive sign for the beleaguered 787 program, which has struggled with continuous delays that created the perception that production is stalled.

In fact, plane No. 7 rolled out the door the night of October 6, making way for a new fuselage to come in the back of the five-position line. That movement on the factory floor is perhaps the best sign that Boeing and its suppliers may have put the worst of the 787’s production problems behind them, and that they are now on a trajectory to start regularly delivering the aircraft.

“Different parts of the factory are getting the rhythm. The supply chain is getting the rhythm,” said Terry George, 787 director of operations for Spirit AeroSystems, Inc. in Wichita, an independent company that makes the nose section of the 787. “It can work, and it will work.”

The 787 production system is perhaps the most challenging in the world because Boeing designed the aircraft to be built from large subassemblies made by prime contractors worldwide and flown to final assembly in Everett. The concept proved difficult to render and caused significant delays, as some contractors struggled to build their parts on time.

On October 6, a ground vehicle pulled the seventh Dreamliner into a nearby paint hangar for finishing. The aircraft will be the first to go to All Nippon Airways.

Perhaps the most startling sight during a recent visit to the Everett facility was a large white tent just south of the paint hangar. Inside, on 787 No. 2, workers were installing 18 titanium plates to fix the wing-to-body join problem. Boeing will fix the first 15 aircraft either in the tent or at nearby facilities, such as Aviation Technical Services, an aircraft-overhaul facility.

After that, Boeing’s prime contractors in Japan will install the plates, said Boeing spokeswoman Mary Hanson.

The increasing production of 787s will eventually overwhelm Boeing’s ability to store them in Everett while waiting for certification from the Federal Aviation Administration. Some of the aircraft probably will be flown next year to Boeing facilities in San Antonio, Texas, Hanson said.

The wing-body join flaw first surfaced in June, and prompted Boeing to abort the 787’s “first flight” after the Paris Air Show. While the plane is said to be technically flyable, the problem prevented it from starting the FAA certification process. Boeing officials now expect to fly the first 787 late this year.

“The faster that they can fly the aircraft and move ahead with the program, the better it is for everyone involved,” said Doug Royce, aviation analyst for Forecast International Inc. in Newtown, Connecticut. “It’s not a question of market, it’s a question of how are you going to get the aircraft into the hands of customers and get their money.”

Physically, the line is now starting to look as it should. Computers and scaffolding that once cluttered the production area are now largely cleared away. This week, four partially assembled 787s were lined up nose to tail, with the sections of a fifth clustered behind the line.