UPDATE 1-New 787 schedule "weeks away"- Boeing engineer

* Already two years behind schedule

* More than 850 orders for revolutionary aircraft (Adds quotes)

By Karen Jacobs

ATLANTA, Aug 6 (Reuters) - Boeing Co (BA.N) is "weeks away" from issuing an updated test flight and delivery schedule for its long-delayed 787 Dreamliner, the program's chief engineer said on Thursday.

The company announced another delay for the first flight of the revolutionary carbon-composite aircraft in June, and has not released a new target date.

Airlines, which have ordered more than 850 of the planes, are eager for Boeing to issue the new schedule.

"I think we're just weeks away from doing that," chief engineer Chris Musoke told a breakfast meeting of the Organization of Black Airline Pilots in Atlanta.

The aircraft, already two years behind its original schedule, was set to fly in the second quarter of 2009. It was delayed so Boeing could address a structural problem.

The 787 will undergo rigorous tests to ensure the problem has been addressed before the new schedule is released, Musoke said.

"Obviously, we've disappointed our customers," he said. "We have to stick to our plan whenever we lay it out and perform to it."

Chicago-based Boeing and rival Airbus, a unit of EADS (EAD.PA), have struggled as carriers and cargo operators grapple with the global recession. (Reporting by Karen Jacobs in Atlanta. Writing by Kyle Peterson, editing by Gerald E. McCormick and Ted Kerr)