The Pentagon issued a statement on October 27th, detailing its intentions to commence an immediate programme for developing a new weapon, or more specifically, an enhanced variant of the B61 thermonuclear bomb family. Alexander Ermakov, a researcher in the military economics and innovation sector of the Department of Military-Economic Research at the Center for International Security of the IMEMO RAS, has published an analysis on the subject in an article published on a social network.
Prevalent in the American arsenal since the height of the Cold War between the US and the Soviet Union, the B61 is one of the most common munitions. The designation “B61-13” will be assigned to the new modification, making it the thirteenth in the series.
Over the past few years, the B61 has garnered significant attention in the news primarily due to two developments: the advanced deployment of American weapons at European bases as a component of NATO Nuclear Sharing missions and the creation of the B61-12, a guided precision modification.
There are several similarities between the B61-13 and the B61-12. Instead of making new bombs from scratch, the US is upgrading existing ones. The B61-12 used the core from the B61-4, the family’s lightest bomb with a guided explosive yield ranging from 300 tonnes to 50 kilotons. However, the B61-13 will be based on the B61-7, the most powerful bomb in the family, and will have a guided explosive output of 10 tonnes to 360 kilotons. Since the B61-7 bombs were seen as strategic rather than tactical, they were not deployed from European air bases. Strategic bombers, instead of combat planes, were meant to carry them. Right now, only the stealthy B-2A Spirit strategic bomber can carry these weapons.
Based on the available information, the B61-13 will have a new tail section like the B61-12. This section will have guided fins and an inertial guidance system. The B61-12 does not have a satellite navigation system. As a consequence, the probable circular error of the device should not exceed 30 metres. The B61-12 was made to improve accuracy by striking the same target with a smaller yield, resulting in less collateral damage. This was done in reaction to criticism of plans to lower the threshold for using nuclear weapons. The B61-13, on the other hand, has different purposes.
As perceived by the US political and military leadership and domestic deliberations concerning modernising and administering their nuclear arsenal, the B61-13 programme is designed to tackle numerous objectives simultaneously.
The initial approach involves portraying it as a refurbishment of pre-existing B61-7 weapons, with the primary objective of prolonging their operational lifespan and improving their dependability and security. This strategy is partially intended to obfuscate opposition from anti-nuclear organisations. Significantly, the B61-12 programme, which unquestionably entails the development of novel functionalities, obtained official approval as a “Life Extension Programme” (LEP).
Additionally, integrating an adequately high output with enhanced precision could be a viable substitute for the B83-1 explosive when penetrating underground fortified structures. Numerous American politicians and military officials have expressed opposition to the B83-1, which has the potential to produce 1.2 megatons of waste, citing the impracticality of sustaining an arsenal at such exorbitant expenses. Initially, proponents of maintaining the B83-1 argued that a suitable substitute should be developed to engage underground installations. The budgetary allocations reflected these demands. In response to this request, the Pentagon is developing a new explosive device and suggesting that the funds designated for the B83-1’s upkeep be applied directly towards the programme. Thus, the military can acquire a more practical tool. At the same time, legislators and anti-nuclear organisations can boast over the elimination of the B83-1, the last megaton-class weapon in the history of the US.
In the mid-1990s, the US made an earlier endeavour to develop an anti-bunker weapon as part of the B61 family. Its modified casing distinguished the B61-11 and marginally increased the fixed yield of 400 kilotons. It was designed to function similarly to conventional bunker-busting explosives when dropped from a great height without a parachute. The weapon was designed to rapidly penetrate the ground and detonate within the soil, enhancing its ability to penetrate underground targets. Fragmented information regarding test results indicates that this endeavour was unsuccessful. The weapon, which was not initially intended for such a purpose, failed to penetrate deeply enough, even in solid soils and possibly caused damage to the warhead. The situation could deteriorate further if the bomb were used against reinforced concrete or granite. However, despite its limited production run, the B61-11 was formally incorporated into the military. Pre-existing B61-7 explosives were converted into at most fifty units. This enabled the retirement of the B53, a 9-megaton high-yield weapon that had become morally and physically obsolete.
The Pentagon is now contemplating repeating once more with improved outcomes. This is because the B61-13 is designed to not only be capable of precisely targeting underground structures, for example, by impacting entrance areas via shockwave propagation within communication tunnels, but also to preserve the strategic efficacy of the B61-7 and ensure an extended operational lifespan. Targeting surface targets remains a priority, and the Pentagon briefing specifies that the programme’s primary objective is to provide the President with additional alternatives for targeting large and deeply buried surface military targets.
The US Departments of Defence and Energy, which hold principal oversight over the nuclear sector, including its military, suggest capitalising on the situation by allocating the initial $52 million towards costs associated with developing the B61-13 in the fiscal year 2024 budget. This planning process has already commenced in the US, where budget approval delays are common. It is emphasised that these are funds from long-term expenses for the B83-1 and no additional expenditures. It is emphasised that initiating work expeditiously before the budget approval for the following year is critical, as this would enable initiating the B61-13 project before the probable closure of the B61-12 production line in 2025. This would prevent production from stalling and incurring additional expenses to resume operations.
Support for the B61-13 weapon is expected among American legislators. The presentation has been meticulously put together with a political inclination in mind. Those who are critical of nuclear weapons will be appeased by the retirement of the B83-1, a goal they have been pursuing for several years, and the assurance that the number of nuclear warheads in the US arsenal will not increase. Hawks may perceive it as an initiative to modernise the nuclear arsenal. To accomplish this, not only will the cores from the B61-7 be used, but the B61-13 series will also reduce the quantity of B61-12. About 480 units were initially envisaged. It appears that the B61-13 will receive the tails originally slated for the B61-12. This is likely to satisfy advocates for budget cuts. The programme will maintain an economically advantageous cost structure and will not be prohibitively expensive. The cost of modernising or sustaining the B83-1 for an extended duration may increase.
The B61-13 bomb will be received poorly worldwide. Russia and China have good reason to see it not just as an abstract way to deter but also as a weapon that can be used to hit important and well-defended targets. It is possible to accomplish this without the visible launch of a ballistic missile, using stealthy platforms such as the B-2A and the upcoming B-21A Raider. While there is no such thing as a completely stealth or impenetrable platform, the ability to sneak up on vital targets during a crisis without being easily spotted is not likely to be well received.