The United States has reached the halfway point in the production phase of its W76-1 nuclear warhead life extension program (LEP) effort, according to the head of the National Nuclear Security Administration (NNSA).

Frank Klotz told reporters Oct. 29 the United States expects to complete the W76-1 LEP during fiscal year 2019. The goal of the W76-1 LEP is to extend the original warhead service life from 20 to 60 years.

Trident II missile being deployed. Photo: DoD.
Trident II missile being deployed. Photo: DoD.

The W76 is a 1970s-era submarine launched ballistic missile (SLBM) system first introduced into the stockpile by the Navy in 1978. It is deployed with the Trident II D-5 missile on the Ohio-class nuclear ballistic missile submarines.

The W76-1 LEP first unit was completed in September 2008, according to prime contractor Pantex. The Federation of American Scientists, a nuclear watchdog group, said the W76-1 LEP also involves changes to both the reentry body and the warhead package: replacing detonators; replacing chemical high explosives; refurbishing the secondary; adding a new arming, fuzing and firing (AF&F) system; adding a new gas reservoir and transfer support system; and a new lightning arrestor connector.

The NNSA this summer also performed the first flight and drop tests for the latest variant of the W88 nuclear warhead. The agency said on its website the two successful tests provided data for the W88 ALT 370 to move forward. The Critical Radar Arming and Fuzing Test (CRAFT) was the first flight test of a prototype radar for the W88 ALT 370.

CRAFT demonstrated how the radar performed during reentry through plasma generated by the hypersonic speeds at which the warhead travels. The drop test mimicked a crane accidentally dropping the re-entry body onto a concrete surface to develop evidence that it would remain safe during an accident. The W88 is also used on the Trident II SLBM.

Klotz’s remarks came at a Defense Writers Group breakfast in Washington.