Reason No. 2, perhaps, that those 787 Dreamliners are so far behind schedule: long bathroom breaks at the North Charleston plants where workers piece together portions of the fuselages.

Employment has surged to more than 3,000 workers at the company's local campus as Boeing seeks to ramp up production of its hot-selling new jet. But male employees have complained that they are forced to share only a handful of bathrooms within the two existing industrial buildings.

The situation recently caught the attention of a union that represents some of the workers from the Puget Sound area in Washington who have been temporarily assigned to the Lowcountry plants.

Tom McCarty, president of Seattle-based Society for Professional Engineering Employees in Aerospace's Local 2001, and other labor officials traveled here last month to discuss the local working conditions with their roughly 100 union members at Boeing Charleston.

The male workers spoke of lines that, at times, snake out of the restroom areas.

"Sometimes, there's a waiting line, and the waiting line isn't insignificant," McCarty said.

Female employees reportedly have not faced a similar problem, likely because fewer women work at the plant, he said.

McCarty said he requested a meeting with local Boeing officials, who initially agreed, but pushed back the sessions to a point where the groups never were able to get together.

Boeing Charleston spokeswoman Candy Eslinger would not disclose the number of bathrooms on site, saying only that the facilities met local building code requirements. She said the company added two modular restrooms outside the plants last year.

McCarty, a 37-year Boeing employee, said he's never come across this situation in one of the company's buildings before.

He said it reflects the glitches that have pushed back the first 787 delivery by nearly two years. Production problems at the airplane's worldwide network of vendors -- Reason No. 1 for the delays -- have forced Boeing to take more control of its far-flung supply chain.

McCarty said management "has been in got-to-make-it-work mode, and that's evident at the Charleston facility. They're scrambling."