This story was updated Jan. 19 to clarify the source of a quote as assistant secretary of the Air Force for acquisition, technology, and logistics Andrew Hunter, not a Northrop official.
The new Sentinel intercontinental ballistic missile program being developed by the Air Force and Northrop Grumman will cost 37 percent more than expected and take at least two years longer than previous projections before achieving initial operational capability—compelling the service to extend the life of some of its Minuteman ICBMs, senior service and Northrop officials told Air & Space Forces Magazine.
Just before close of business Jan. 18, the Air Force sent Congress notification of a Nunn-McCurdy breach on the Sentinel program. 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.”
The Sentinel’s Program Acquisition Unit Cost—which includes development, acquisition, and construction costs—is increasing by 37 percent, making its Nunn-McCurdy breach “critical,” the senior official said. Its Average Unit Procurement Cost—which is focused on acquisition costs—will rise by 17 percent. The two figures are not additive.
An Air Force spokesperson said that when the program was baselined in 2020, the PAUC was $118 million. The 37 percent increase now puts that estimate at $162 million for the PAUC, the spokesperson said.
Under Nunn-McCurdy, programs in “critical” status are assumed to be headed for termination, unless the Secretary of Defense certifies there’s no alternative. Defense Secretary Lloyd Austin is expected to make that certification, given the time it would take to start over and the urgency with which the 50-year-old Minuteman missiles must be replaced.
The estimated cost of Sentinel before the “program deviation” was $95.3 billion, indicating its new cost could be more than $125 billion. The Air Force expects to have a new cost and schedule for Sentinel by summer 2024, assistant secretary of the Air Force for acquisition, technology, and logistics Andrew Hunter said. That assumes the Nunn-McCurdy process takes its full course and the program is allowed to continue.
The cost and schedule growth stems largely from the ground element of Sentinel. These include the command and launch segment—silos and launch control facilities, which will be “significantly bigger” than those for Minuteman—as well as the communications infrastructure the Air Force had hoped to reuse from the Minuteman, but which is too old and lacking in necessary bandwidth to do the job. A big element of that will be cabling and cable ducting which must be replaced, as well as land easements and other infrastructure expenses not well understood when the program baseline was set.
Inflation also played a role. Air Force Secretary Frank Kendall has also noted Sentinel has struggled with issues such as adequate labor and security clearances for workers.
While there is some escalation in the cost of the LGM-35A missile itself, it was not a major factor in the Nunn-McCurdy breach, Hunter said.
“There’s been a little bit of cost growth on the missile side, but comparatively much less than what you see with command and launch segment. (The missile) would not probably, on its own, have triggered any kind of a breach in terms of cost,” he said.
The schedule slip also adds cost to the program, since engineers and workers have to be kept on the project longer than expected. Moreover, some previously unexpected costs “were not included” in the Milestone B review of the program in 2020, a USAF official said.
Sentinel and Minuteman will also have to operate simultaneously for a time, creating challenges for the communications network.
In years to come, Hunter said, “there will be significant budgetary changes as a result of this cost growth, on both the Sentinel and Minuteman side.”
Work continues on the program while the Nunn-McCurdy process plays out; no stop-work order has been sent to Northrop Grumman or its subcontractor team.
While no Sentinel-related financial changes are expected to the fiscal 2025 budget request soon to go to Capitol Hill, the cost increases will be reflected in the five-year program objective memoranda (POM).
According to the Sentinel’s Selected Acquisition Report for 2022, procurement accounts for $61.6 billion of the program cost estimate, while research, development, test and evaluation is $25.5 billion and military construction is $8.7 billion.
In order for Sentinel to continue, Defense Secretary Lloyd J. Austin III must certify the program is crucially needed. The certification requires five conditions be met:
- The program must be deemed essential to national security.
- The root cause of the overrun must be clearly understood.
- New cost estimates must be validated by the Pentagon’s Cost Assessment and Program Evaluation shop as reasonable.
- There are no lower-cost alternatives to the program.
- The program is a higher priority than other programs that must be reduced or eliminated to pay for the overrun.
A Nunn-McCurdy breach must also be addressed by restructuring the program in a way that corrects the root cause of the overrun, and new program milestones must be set.
Programmatically, the Sentinel is expected to go through a series of “rolling” critical design reviews in the coming months, a Northrop official told Air & Space Forces Magazine.
There may be ways to mitigate the two-year delay, he said.
“There’s IOC and there’s FOC,” Hunter noted, referring to Initial Operational Capability and Full Operational Capability. “IOC is when you get started and FOC is when you are done. What really matters for Minuteman III is when are you done. … FOC is obviously farther out in time. So there will be options to really look at to how do we perhaps keep [the] FOC date from moving as much as other parts of the program.”
The Sentinel program calls for production of 634 missiles. Of those, 450 will replace Minuteman III missiles now in silos, 184 will be used to demonstrate periodically—to allies and potential adversaries alike—that the system works, and 25 will be developmental test vehicles.
The program also calls for dozens of launch control facilities; maintenance and management buildings; integrated control centers at F. E. Warren, Malmstrom, and Minot Air Force Bases; weapons storage facilities; 56 loading and transport vehicles, and some 7,500 miles of cabling, a Northrop official said. Collectively, the massive program is “like five MDAPs (Major Defense Acquisition Programs) combined,” he said.
In response to the Nunn-McCurdy notification, Northrop said it and the Air Force “continue to make significant progress on this highly complex program, achieving key milestones to mature the design and reduce risk.” As part of its engineering and manufacturing development contract, “our team is committed to supporting the Air Force as it assesses and updates acquisition cost forecasts for the future phases of the program, to include construction projects, production, and deployment of the weapon system.”
“We are focused on continuing to perform and meet our commitments under the EMD contract as we move toward delivery of this essential national security capability,” a spokesperson added.
Northrop CEO Kathy Warden will preside over the company’s fourth-quarter 2022 earnings call on Jan. 25.