Boeing announced Tuesday it has won a ten year, 1.1 billion dollar contract to provide depot maintanance for the US Air Force's KC-135 tanker fleet.

The deal represents a renewal of contract that Boeing has had since 1998 to provide scheduled and unscheduled maintenance for more than 200 of the aircraft.

The work will be performed at facilities in Texas, Oklahoma and Missouri, it said.

The company said it has reduced the time the aircraft are out of service for maintenance by 19 percent, which it said translates into a 15 percent cut in cost per aircraft.

"Leveraging 75 years of tanker manufacturing and maintenance expertise, we can commit to a low-risk, cost-effective solution that offers a potential bridge to the KC-X," Pat Finneran, president of Boeing Support Systems, said in a statement.

Boeing and a team from EADS and Northrop Grumman are competing to build the KC-X, the air force's next generation tanker and replacement for the KC-130.