SEATTLE (Reuters) - The elongated 787-9 version of Boeing Co's <BA.N> Dreamliner made its maiden flight on Tuesday, passing a key milestone for a plane that should be more profitable both for Boeing to sell and for its customers to operate.

The jet, which left the ground at 11:02 a.m. PDT (1802 GMT), has room for 290 passengers, 40 more than the current production model, and has about 300 more nautical miles of range. Those factors mean Boeing can charge more for the plane and airlines can sell more seats on long-haul flights.

(Reporting by Alwyn Scott; Editing by Gerald E. McCormick)