Lockheed Martin Corp. of Bethesda won a $30 million contract to deliver new computers for the aging B-52 bomber that will enable the Air Force to continue flying the plane until 2050.

The B-52 was developed in the 1950s to carry nuclear bombs over long distances. The Air Force used the bomber, with wings that span 185 feet, to drop conventional bombs during the Vietnam War. The bomber began carrying cruise missiles for attacks on far-away targets in the 1980s.

The bomber's latest computers will give it the ability to carry even more types of weapons, said Louis DeSantis, a vice president at Lockheed Martin overseeing the contract.

Lockheed Martin declined to give more details about the bomber's future capabilities, but the plane's greater flexibility is part of the Pentagon's efforts to make the military lighter and faster.

The Air Force first installed computers that helped navigate the plane and coordinate weapons in the early 1970s. The new computers designed by Lockheed are the first replacements for the bomber's original computers. Faster, more powerful and with lots more memory, two of the new computers will replace four old computers on each bomber.

The new computers will allow the aircraft to give up its reliance on the custom-built software now running the electronic insides of the bomber and instead take advantage of standardized software sold by private companies. The aircraft is also likely to be outfitted with new screens in the cockpit to display the data generated by the computers.

Lockheed has already delivered 21 computers to the Air Force for evaluation on test planes. The current contract signals that the Air Force is satisfied with the prototypes and has hired Lockheed Martin to build operational computers for working bombers. The company said it expects to begin installing the computers next year and complete the work by 2009.

Engineers at a Lockheed plant in Owego, N.Y., will build more than 180 computers for the fleet. Workers at the same plant, then owned by International Business Machines Corp., also designed the bomber's first computers.

The computers will give the B-52 the ability to carry more types of weapons.