WASHINGTON - Boeing Co (BA.N) was selected to build the U.S. Air Force's next training jet in a contract worth up to $9.2 billion over the life of the program, the Air Force said on Thursday.

Boeing teamed up with Sweden's Saab AB (SAABb.ST) to develop a new plane for the competition, beating out Lockheed Martin Corp (LMT.N) and Leonardo DRS (LDOF.MI).

The Air Force plans to purchase 351 of the jets. The service expects the program to reach full operation in 2034.

Boeing did not immediately respond to a request for comment.

The win is significant for Boeing, which reorganized its defense business more than a year ago in the hopes of a "franchise level" win such as the trainer.

Landing big defense contracts had been difficult for Boeing, but Leanne Caret, the chief executive of Boeing's Defense, Space & Security since February 2016, has helped the company win more contracts.

Boeing beat out Lockheed, which was offering a modified version of its T-50 training jet developed jointly with Korea Aerospace Industries Ltd <047810.KS> and also beat Italy's Leonardo DRS, which offered the T-100, a modified version of the Italian aerospace company's M-346.

The Air Force wants to replace its aging fleet of T-38 planes, which are nearly 50 years old, and analysts have said it could eventually buy up to 600 planes.

This award from the Air Force comes after Boeing has had trouble delivering to the Air Force its new in-air refueling jet, the KC-46.- Reuters