New Sentinel nuclear warhead program is 81% over budget. But Pentagon says it must go forward

WASHINGTON — The new Sentinel warhead program is 81% over budget and is estimated to cost nearly $141 billion. Yet the Pentagon is pushing ahead with the program because, given the threats from China and Russia, it has no choice.

The Northrop Grumman sentry program is the first major upgrade of the ground-based component of the nuclear trinity in more than 60 years and will replace the aging Intercontinental ballistic missile Minuteman III.

It involves not only building a new missile, but also modernizing 450 missile launch sites in five states, their launch control centers, three nuclear missile bases and several other test facilities.

The size of the program has previously raised questions among government regulators about whether the Pentagon can handle it all.

Military budget officials said Monday that when they determined the estimated cost of the program, their full knowledge of the modernization needed “was, in retrospect, insufficient to be able to make a high-quality cost estimate,” Bill LaPlante, undersecretary of Defense for acquisition and sustainment, told reporters in a phone call.

The large cost overrun led to what is known as a Nunn-McCurdy violation, which occurs when the cost of developing a new program increases by 25 percent or more. Under the law, the undersecretary of defense for acquisition must then conduct a thorough review of the program to determine whether it should continue; otherwise, the program must be terminated.

“We fully understand the magnitude of the costs, but we also understand the risks of not modernizing our nuclear weapons and not addressing the very real threats that we face,” LaPlante said.

The Nunn-McCurdy study found that most of the cost growth stems from Sentinel’s command and launch segment. This segment includes the extensive communications and control infrastructure that allows missile launchers, which are on standby for 24 hours or more in underground launch centers, to connect to missiles in silos and fire them when commanded to do so.

The program will be restructured, La Plante said. Some of the modernization planned for the launch facilities will be scaled back, and part of the ambitious replacement of an entire network of underground cabling, known as Hicks cables, could be revised in favor of a number of more affordable alternatives.

The higher costs will also eventually be offset by cuts to other programs, said Gen. Jim Slife, vice chief of staff of the Air Force. However, the Air Force estimates that most of the cost increases for the Sentinel program will occur outside the next five fiscal years of budget planning, meaning that tough choices about program cuts won’t have to be made right away.