Charles Verdon, the Deputy Administrator for Defense Programs at the National Nuclear Security Administration (NNSA), informed members of Congress of the issue during a hearing on Sept. 25, 2019. NNSA oversees the development, construction, and dismantlement of U.S. nuclear weapons. The W88 ALT 370 is an upgrade for existing W88 warheads that reportedly consists of improved arming, fuzing, and firing components. The B61-12 is a modernized variant of the B61 family of nuclear gravity bombs that leverages warheads from older B61-4 bombs and various components from those weapons, as well as from B61-3s, -7s, and -10s. It also adds a precision guidance tail kit. The B61-12s, which you can read about in much more detail in this past War Zone feature , will replace these older B61s, and potentially other nuclear bombs.

Concerns about the reliability of commercial-off-the-shelf capacitors, each of which cost just $5, the Department of Energy had been planning to use in two future nuclear warhead designs will delay both programs by at least a year and a half and could result in up to a whopping $850 million in additional costs. The W88 ALT 370 warheads for the U.S. Navy's Trident D5 submarine-launch ballistics missiles and the U.S. Air Force B61-12 nuclear gravity bombs , the latter of which are already set to be worth literally twice their weight in gold each, are seeing impacts from the decision to switch to a more robust piece of circuitry.

The W88 ALT 370 and B61-12 designs both used the same commercial capacitors in an effort to help control costs. Verdon insisted to legislators that there was no indication that these components would fail under normal circumstances.

"Early tests on the capacitors now in question and subsequent tests including component, major assembly, and full-up integrated system flight tests demonstrated that these components meet requirement today," Verdon told lawmakers. "Industry best practices were used to stress the components beyond their design planned usage as a way to establish confidence that they will continue to work over the necessary lifetime of the warhead. During stress testing, a few of these commercially available capacitors did not meet the reliability requirements."

This, in turn, shook NNSA's confidence that all of the capacitors would be able to work reliably across the expected life cycles of the W88 ALT 370s and B61-12s. These weapons are expected to remain in the active stockpile for at least between 20 and 30 years after they enter service. The U.S. Air Force had hoped to receive its first examples of the B61-12 next year. It's unclear when the Navy might have originally expected to start getting the W88 ALT 370s, but NNSA had planned to finish construction of the first of these upgraded warheads by the end of this year.

NNSA is now replacing the $5 capacitors with new, more robust ones that cost around $75 each. Verdon said that this could add between $120 and $150 million to the total cost of the W88 ALT 370 program and between $600 and $700 million to the B61-12 effort. He warned that the combined costs could potentially rise to more than a billion, depending on how the process goes. Each of these programs is now facing its own schedule delay of between 18 and 20 months, as a result.