The US Air Force's next strategic heavy bomber has passed a critical design review. On November 28 to 30, the US Defense Department carried out a multi-disciplined technical evaluation of the proposed B-21 Raider to see if its design was stable and mature enough to warrant moving on to manufacturing and flight testing, and the evaluation has determined that significant progress has been made on the three-year old project.

The United States is almost unique in the field of strategic bombers, where other air forces rely on tactical bombers to deliver ordnance, only the US and Russia still have heavy, long-range bombers as part of their active inventories. Currently, the US Air Force fields three heavies developed during the Cold War, the B-52 Stratofortress, the B-1 lancer, and the B-2 Spirit.

Though these aircraft have served well for decades and the B-52 is so over-engineered that the grandchildren of the original pilots are now flying them, the US strategic bomber wings are showing their age and their technological obsolescence. It's for this reason that the Air Force Rapid Capabilities Office set up the Long Range Strike Bomber program (LRS-B), which led to the B-21's development by Northrop Grumman.

The purpose of the B-21 will be to provide a long-range stealth platform with a high survival capability for penetrating enemy airspace to deliver conventional and thermonuclear weapons. It's also expected to handle, with the aid of long-range fighter cover, any future anti-access and area denial systems that might be fielded against it.

Though very few technical details have been released, it's expected to have a basic design similar to the B-2. If all goes according to plan, it's anticipated the B-21 will enter service by 2025, when it will operate alongside other strategic bombers before eventually replacing them.

"The Air Force is pleased with how the program is moving forward," says Air Force Secretary Heather Wilson. "The B-21 Raider program is on the right track to make continued progress over the next few years as it now transitions from the design phase into a robust manufacturing phase that will ultimately produce our first B-21 test aircraft."

Source: US Air Force