There has been great secrecy surrounding the project, which still has a secret price tag.
Last weekend, manufacturer Northrop Grumman showed off the B-21 Raider for the first time.
Each copy is estimated to cost around 650 to 675 million dollars, according to Hans Kristensen.
They must be able to carry both conventional bombs and cruise robots, but also weapons equipped with nuclear warheads.
The first examples should be operational in the mid-2020s, and the US Air Force has ordered at least 100 B-21s to replace the older B-1 and B-2 bombers that were developed during the Cold War and began to be used by the US air force in the 1980s and in the 1990s.
- B-2 is getting old and is very expensive to operate.
It was built to withstand fast, low-altitude attacks in the Soviet Union.
The B-21 is a much more versatile aircraft.
It can be used for several different purposes, including dropping bombs from a high altitude, says Hans Kristensen.
American B-21 Raider bomber unveiled at manufacturer Northrop Grumman's factory in Palmdale, California.
Photo: US Air Force/Joshua Carroll December 2, 2022
Bombers from the 50s are being modernized
However, the older B-52 bombers developed by Boeing in the 1950s are retained.
The lifespan of the B-52s is now set to be at least 80 years thanks to modernization, according to the US Congressional report on the project.
Hans Kristensen, who is one of the world's leading experts on US nuclear forces, believes that the new B-21 bombers will operate in Scandinavia in the same way as the B-52s have done in recent years.
- You often see them also flying over Sweden.
The past year has seen that northern Sweden has started to become an important operational area for strategic bombers on their way into Europe.
After all, it is on their path towards the large naval base in Murmansk, as well as towards St. Petersburg and further towards Moscow, but also when they fly in and support operations around, for example, the Baltics and operational areas around them.
So it is a crucial operational area for the strategic bombers.
Swedish Jas 39 Gripen fighter jet escorts American B-52H Stratofortress bomber as it makes a low-altitude overflight over Stockholm.
Photo: US Air Force September 1, 2022
More nuclear bases
The new bombers will be able to carry B-61 nuclear bombs stored in five NATO countries in Europe (Germany, Netherlands, Belgium, Italy and Turkey).
The B-61 bombs are currently undergoing an extensive modernization where in December they will begin to be replaced by a new version (B61-12) that has higher accuracy because they can be directed at targets.
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Hear William Alberque, director at the renowned International Institute for Strategic Studies, analyze how Sweden's participation in NATO's nuclear weapons management might look.
Photo: SVT/US Air Force
Here you can read about Russia's nuclear weapons development in Sweden's vicinity.