The US has announced its intention to create a new variant of the B61 nuclear free-fall bomb, which is the main type of nuclear munitions for the Air Force. And for the bomb, developed in 1963, this will already be the thirteenth version.
The decision to create a new bomb has already received a “green light” from the administration of the US president because it “reflects the changing security situation and growing threats from potential adversaries.” The very project of the new bomb with the B61-13 index will be based on the newly developed version of the B61-12 but will differ in significantly greater power.
If the B61-12 has a choice of 0.3-, 1.5-, 10- or 50 kilotons (the power is selected during the pre-flight preparation of the bomb), then the declared power for the B61-13, as for the B61-7, that is, up to 360 kilotons, as stated in the Pentagon’s message. Also, it is the B61-13 that is supposed to replace a certain number of B61-7s that are being decommissioned, and the new version is supposed to get a higher accuracy and safety level.
At the same time, the US Defense Ministry noted that the number of produced B61-13s will not change the total number of nuclear bombs in the arsenal. That is, their production will be at the expense of reducing the production of B61-12 and decommissioning B61-7, as well as one more nuclear bomb – B83-1 with a capacity of 1.2 megatons, which is the largest nuclear munition of the United States.
The cost and terms of work have not yet been announced, but for comparison, it is possible to cite the cost of the B61-12 program at $9.6 billion with the production, according to preliminary plans, of 400-500 units. The main feature of the B61-12 was the accuracy of +/- 30 meters compared to +/- 110-170 meters in the B61-11 version, which allowed, according to the Pentagon’s calculations, to limit the power of the charge to hit highly protected targets with a ground explosion.
But given the plans in the B61-13 to combine similar high accuracy and 7 times more power, we are talking about creating ammunition that is designed to hit even more fortified underground facilities. Suppose we are talking about a power of 360 kilotons. In that case, this will allow the formation of a crater up to 66 meters deep with a radius of up to 275 meters in the event of an explosion on the surface, which means the possibility of destroying much deeper objects.
In the event that the B61-13 will have the ability to sink into the ground, as in the B61-11 with a capacity of up to 400 kilotons, then the possibility of hitting the most protected strategic objects becomes available.
It is important that the B61-13 can be carried by virtually all aircraft, both tactical and strategic, due to its relatively low weight of approximately 320 kg (540 kg for the B61-11). At the same time, for the most important tasks, the doctrine of the use of free-falling bombs in the USA provides for the use of strategic bombers B-2 and later the B-21 Raider, which is already preparing for its first flight.