The National Nuclear Security Administration (NNSA) made post-Cold War history in its 2021 budget request, which seeks funds to develop a new sea-based nuclear warhead designated Mk7 W93 — a weapon designed to be rapidly upgradeable and serviced outside of the civilian agency’s Pantex Plant in Amarillo, Texas.
This will be the first new warhead design in decades – specifically the first since the Cold War that is not a refurbished model of a weapon already in the field.
The NNSA had not released its detailed budget justification at deadline Monday for Weapons Complex Morning Briefing. That detailed document could include the cost and nature of the W93 work planned for the fiscal year that begins Oct. 1. The DOE budget in brief said the NNSA planned “concept and Assessment Refinement activities” for W93 in 2021.
The W93 was most recently known as the Next Navy Warhead in the agency’s declassified plans, and as the Interoperable Warhead-2 prior to that. The NNSA’s fiscal 2020 Stockpile Stewardship and Management Plan shows a notional 2034 first production date for W93, with early feasibility studies starting in the current 2020 federal budget year.
The weapon would be based on a design already test-fired underground at the Nevada National Security Site before yield tests ended in the 1990s, according to a source with knowledge of the proposal for the weapon. It would initially be suitable for use on submarine-launched intercontinental ballistic missiles, but could be tweaked for use on other sea-based weapons, this person said.
To begin, W93 would tip the eventual successor to the Navy’s Trident II D5 submarine-launched ballistic missile, which would be carried through the 2080s by the next-generation Columbia-class submarines. The first of 12 Columbia boats is slated to go on patrol in 2031. The United Kingdom’s nuclear weapons are also delivered via Trident missiles.
The 2020 Stockpile Stewardship and Management Plan notionally calculated the NNSA’s share of development at an inflation-adjusted $14 billion.
The proposed W93 notionally could be serviced by the military at Pentagon-controlled locations, the source said. Usually, nuclear weapons coming off deployment for maintenance head to Pantex. Creating an alternative to the plant would potentially shorten the weapon-servicing supply chain.
