B61 is an air-dropped battlefield/tactical nuclear weapon. It is the B-2’s primary strategic weapon equiping both the F-16 and F-15E in the forward-deployed, allied extended deterrent role, as well as the B-2.
The weapon was first delivered in 1966, and the B61 Mod 11 introduced in 1997 adds a ground-penetrating capability, enhancing its effect against buried and hardened targets. The weapon incorporates several preselectable yield options tailored to mission requirements.
Work is underway on the B61 Mod 12 Life Extension Program (LEP) begun in 2016 to consolidate the B61-3, -4, -7, and -10 into a single, standardized configuration. The LEP refurbishes the warhead to improve the safety, security, and reliability through 2040. B61-12 also adds a guided tail kit, making it the first precision guided weapon of its type, permitting higher effectiveness at lower yields.
USAF and the National Nuclear Security Administration finished qualification flight-testing on June 9, 2018. The 31 inert test drops greatly exceeded performance requirements, validating nonnuclear components such as arming/fire control, guidance, spin-rocket motors, and software. B61-12 was approved for production and completed operational flight testing on the F-15E and B-2A in 2019. Operational testing included 15 drops, certifying the F-15E as the first aircraft capable of delivering the B61-12 on June 8, 2020.
The Department of Energy conducted nine additional drops, culminating in a full-weapon system demo on the B-2A in July 2020. The F-35A dropped an inert B61-12 for the first time on Aug. 25, 2020, employing it in supersonic flight from its internal weapons bay.
Delivery of the first production example has been delayed two years to 2022 due to technical issues. Future integration is planned on the F-16 and F-35A.
Contractors: Los Alamos National Laboratory (weapon); Boeing (B61- 12 tail kit).
Delivered: 1966.
IOC: 1968.
Production: N/A.
Inventory: Approx. 500.
Operator: AFMC, USAFE.
Deployed Locations: Aviano AB, Italy; Büchel AB, Germany; Ghedi AB, Italy; Incirlik AB, Turkey; Kleine Brogel AB, Belgium; Volkel AB, Netherlands.
Active Variant: •B61. Supersonic-droppable free-fall thermonuclear weapon.
Dimensions: Length 11 ft 8 in., diameter 1 ft 1 in.
Weight: 700 lb; 825 lb (B61-12).
Performance: N/A.
Guidance: None (B61 Mod 1 to 11); unknown, likely INS (B61 Mod 12)
Warhead: One B61 -3, -4, -7, -10, or -11.
Estimated Yield: 0.3 kilotons, 1.5 kilotons, 10 kilotons, 50 kilotons (preselectable).
Integration: B-2A, F-15E, and F-16C/D; NATO: F-16A/B Mid-Life Upgrade (MLU), and Panavia Tornado IDS. Planned: B-21, F-35A.