The U.S. Air Force’s New B-21 Stealth Bomber Is Under Construction

David Axe

Security,

The U.S. Air Force’s new B-21 stealth bomber is scheduled to make its first public appearance in December 2021. But there’s a lot of work to do before the plane can debut.

The U.S. Air Force’s new B-21 stealth bomber is scheduled to make its first public appearance in December 2021. But there’s a lot of work to do before the plane can debut.

The U.S. Air Force in 2015 awarded Northrop Grumman a $23-billion contract to develop the new bomber as a partial replacement for the service’s existing fleet of around 160 B-1, B-2 and B-52 bombers.

More than four years later, work is well underway on the first B-21 test plane, John Tirpak reported at Air Force magazine. Northrop is building the bomber at a secretive facility in Palmdale, California that previously manufactured Global Hawk spy drones.

“We’re ready to start actually building parts,” Randall Walden, head of the U.S. Air Force’s Rapid Capabilities Office, which oversees B-21 development effort, told Tirpak.

Many aspects of the B-21’s design remain classified. The Air Force has released a crude artist’s impression of the plane that depicts a flying-wing design that’s similar to the B-2’s design but lacks the older bomber’s serrated “dogtooth” trailing edge.

Northrop added the dogtooth edge to improve the B-2’s low-level performance. The B-21, however, is designed to operate mostly at high altitude, so it doesn’t need the serration.

It’s unclear whether the B-21 has four engines like the B-2 does or just two, Tirpak pointed out. “The consensus among aerospace analysts is that the jet likely uses [Pratt & Whitney’s] F135 engine, which also equips the F-35 fighter,” Tirpak wrote.

Two F135s could generate 56,000 pounds of dry (non-afterburning) thrust, but would require a larger aperture to do so than the four General Electric F118 engines in the B-2, which combine to produce about 68,000 pounds of thrust.

The B-21 is believed to be somewhat smaller than the B-2, with a payload of around 30,000-pounds, just large enough to carry one GBU-57 Massive Ordnance Penetrator precision-guided conventional bomb, the largest in the Air Force inventory.

The Air Force has stated that the B-21, which will be capable of nuclear and conventional roles, would have a pilot-optional mode, effectively transforming it into a remotely-operated drone with the flip of a few switches.