Sentinel ICBM Survives Pentagon Review, But Cost Jumps 81%

The cost overrun on the Air Force’s LGM-35A Sentinel intercontinental ballistic missile is more than twice what was anticipated early this year—81 percent compared to 37 percent—but Pentagon acquisition and sustainment chief William LaPlante has certified that the program must continue, the Department of Defense announced July 8.

The Pentagon also indicated the program will be delayed at least three years, instead of the two previously predicted, and the Air Force alone seemingly must bear the cost of the overrun.

If the program was to continue as it had been previously structured, it would cost $140.9 billion, LaPlante said in a press conference to announce the results of a six-month, statutorily mandated review of the Sentinel he conducted after the Air Force revealed it was in breach of the Nunn-McCurdy Act in January.

The Nunn-McCurdy Act requires the Pentagon to inform lawmakers if a program incurs a cost or schedule overrun of more than 15 percent. Any breach over 15 percent is considered “significant,” while a breach of 30 percent is considered “critical.” For critical breaches, the Secretary of Defense must either cancel the program or certify it to continue as necessary for national security. A Pentagon official said the certification function was delegated by Austin to LaPlante.

The Sentinel program will be “reasonably modified,” LaPlante said, to take out some of the cost overage, but Air Force acquisition chief Andrew Hunter said the final cost will still be similar to the new estimate for the existing program.

“Along with this certification to Congress, I am rescinding the program’s Milestone B and directing the Air Force to come back to me with a plan to restructure the program,” LaPlante said. “Preserving schedule will be a key consideration during this restructuring, but a delay of several years is currently estimated.” He offered no more specific prediction of the delay, previously estimated at two years.

It will take about 18 months to two years to restructure, Hunter said, but work on Sentinel will continue in the meantime.

Northrop Grumman is the prime contractor for designing, developing, integrating, and testing the Sentinel missile, as well as the basing infrastructure that goes with it.

LaPlante said he certified the program is necessary and should continue because it is:

  • Essential to national security
  • There are no alternative programs that can achieve the requirement at less cost
  • The director of Cost Assessment and Program Evaluation agrees that the new costs estimates are reasonable
  • The program is “a higher priority than programs whose funding must be reduced to accommodate the growth in cost”
  • The program’s management structure is adequate to manage and control the program acquisition unit cost

Asked about alternatives considered, LaPlante said the review team examined “about four to five different options,” including extending the aging Minuteman III missiles until 2070, “hybrid options of different ground facilities, mobile versus fixed,” and others.

In every case, either the cost was “prohibitive” versus restructuring the Sentinel “or it didn’t meet the operational requirements that the warfighter had levied on us,” he said.

As for the “root cause” of the problem and whether the program should have advanced to the engineering and manufacturing development phase in 2020, LaPlante said “it’s clear, certainly for the ground segment, that … the department was not at a Preliminary Design Review—PDR—level of maturity at the Milestone B, which was in September of 2020.” The plan for the “ground segment” and “launch element” was lacking key information because building a new ICBM is something the Pentagon hasn’t done in 50 years, he said.  

“The knowledge that we have today is much better than [we had] even have four years ago,” LaPlante asserted.

“It is important to note that this certification does not indicate business as usual,” he added. “The program will be restructured to address the root causes of the breach and ensure an appropriate management structure is in place to control costs.” He said there are “reasons” for the cost growth but “no excuses.”

“We fully appreciate the magnitude of the cost, but we also understand the risks of not modernizing our nuclear forces and of not addressing the very real threats we confront,” LaPlante said.

Hunter indicated the Air Force will be solely responsible for finding the roughly $45.3 billion in additional funds the Sentinel will require, but said the overages will not start kicking in for another five budget years. That means the Air Force has time to restructure its budget to adjust for the ICBM’s higher cost, he said.

Asked what might be cut to pay for the Sentinel, Hunter said “our current cost profile does not suggest that any of the cost growth in the Sentinel program will be realized over the course of the next five years or so—inside the Future Years Defense Program” and it will be “a decision far down the road to decide what trade-offs we’re going to need to make in order to be able to continue to pursue the Sentinel program.”

Those decisions won’t be made until the program reaches the Milestone B decision again, he added.

Hunter also said the cost growth on Sentinel is all still projected at this point.

“So this is future cost growth that we’re projecting and estimating,” he said. “And the reason why we now know about this projected cost growth is because we’ve dramatically accelerated the maturity of the design of the ground segment. That’s where the vast majority of this cost growth resides and is being driven by.”

While Sentinel is being restructured, “we’ll do what it takes to sustain Minuteman III to meet warfighter requirements,” Hunter said.

LaPlante noted that the plan that was reviewed is not the one which will govern the Sentinel from here on out.

“What is going forward in this certification is not that plan, but a modification of that plan, with some changes made to the launch facility to make it more cost effective, as well as less complex,” and to adjust the schedule.

He explained that the baseline launch facility “had a size and a complexity that when we looked at it carefully … could be scaled back.” By reducing the size and complexity, “it also reduces the timeline of doing the transition between the existing system—Minuteman III—and the new system. So both of those were where the changes that are being recommended for the modification.”

When the program is overhauled, Hunter said, “we will bring a new program baseline to Dr. LaPlante for approval, and those numbers may vary slightly from the numbers that we’re discussing today, but that’ll be the new program baseline, and we expect that process to take on the order of 18 to 24 months to complete.”

The Air Force has already taken “proactive steps” to correct the program while the review has been underway, Hunter said.

“Last fall, the Department of the Air Force established a Nuclear Oversight Committee, which is co-chaired by the most senior leaders of the Department of the Air Force,” he said. The committee is responsible for providing oversight of the Air Force’s nuclear enterprise, “including strategic bombers, land-based ICBMs, and nuclear command and control.” The Department of the Air Force also established “a dedicated program executive officer, or PEO, for ICBMs, and are in the process of elevating the commander of the Air Force nuclear weapons center to a three-star,” up from a two-star billet, and “established the Nuclear System Center.”

These steps “demonstrate our dedication to bringing the critically important Sentinel program to full mission capability,” he said.

Air Force Vice Chief of Staff Gen. James C. Slife said the ICBM leg of the nuclear triad is essential to complementing the air- and sea-based legs “amidst an increasingly complex and dynamic security environment, which for the first time includes the People’s Republic of China as a major nuclear armed power and strategic competitor.”

The land leg’s “geographic dispersal creates targeting problems for our adversaries,” Slife said. “Transitioning from the Minuteman III to the Sentinel system through a restructure program is the best way to continue providing these capabilities.” He said the Air Force will “continue working closely with the Department of Defense and other stakeholders to mitigate risk and minimize gaps as we field modernized systems for the future.” The service will continue to “sustain and defend the Minuteman III as [we] have for more than 50 years, while we field a new Sentinel ICBM weapon system.”

Sentinel is a massive program to replace the Minuteman III ICBM deterrent force. It will replace 400 missiles in silos, plus additional missiles for spares and test, and radically overhaul the silos themselves, as well as the launch capsules, communication systems, utilities and civil engineering for the ICBM enterprise.

The Air Force “fully supports the decision to restructure the Sentinel program and is committed to restructuring in a manner that provides robust nuclear deterrent into the future, promotes the most effective acquisition of this critical capability that controls cost and delivers weapons system on a schedule that ensures our ability to sustain the nuclear deterrent,” Hunter said.

The Department of the Air Force’s leaders are “acutely aware that we can and must do more to improve program management and oversight of this vital project. We do not take lightly the once-in-a-generation responsibility to modernize the ground leg of the nuclear triad, and are mindful of the scope and scale of this undertaking, which is unprecedented in contemporary times.”

LaPlante emphasized that the Sentinel is “a historic, multi-generational program to modernize this nation’s nuclear posture. The Nunn-McCurdy review we just completed was of the highest priority. It was detailed, comprehensive and objective. We’ve identified the root causes of the increased costs, and we are already working to . ..move forward. But most importantly, we believe we are on the right path, moving together and forward, and despite the historic scale and complexity, we can do this. We know we have to get this right, and we will.”