The U.S. will rely on existing B-52 jets, like this one landing at England’s RAF Fairford station, until the made-over versions debut.

The U.S. is pushing to upgrade its 60-year-old fleet of strategic bombers to keep them flying into the second half of the 21st century in an effort to deter potential adversaries such as China and Russia.

Air Force officials and military experts have said the refresh of the B-52 bomber—a long-range jet built by Boeing Co. that can carry large loads of conventional and nuclear weapons—is crucial to providing an effective deterrent. The B-52 revamp could cost $11.8 billion, according to Pentagon budget documents in the spring.

The challenge for the Air Force and aerospace suppliers is to refresh long-running programs such as the B-52 while newer systems come online. Upgrading older aircraft takes time as the new systems need testing and the changes have to be staggered so that enough jets remain in service.

Excerpt from WSJ
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