Amid significant delays and cost overruns with the LGM-35A Sentinel program, the US Air Force has assessed that its decades-old fleet of Minuteman III (MMIII) ICBMs could be extended to 2050, according to a new Government Accountability Office (GAO) report. While feasible, such an extension would carry significant risks and complications.
MMIII Extension Feasible But Risky
The GAO report, published on Wednesday, found that prolonging the operations of the MMIII arsenal, maintained by Boeing, is „feasible,” and the Air Force is evaluating options for this extension. However, this approach faces challenges, including a limited supply of parts needed for flight tests crucial to ensuring the missile’s efficacy.
Sentinel Delays and Cost Overruns
The Air Force plans to gradually replace the MMIII arsenal with the new Sentinel. However, in July 2024, the Pentagon revealed that the Sentinel program is years behind schedule and 81 percent over budget, primarily due to unforeseen issues with ground infrastructure. Initial plans to reuse MMIII silos have been scrapped, requiring the construction of entirely new silos.
Senator Criticizes Sentinel Program
Sen. Elizabeth Warren, a Democrat from Massachusetts and a vocal critic of the Sentinel program, stated that „The Air Force repeatedly misled Congress about the need and real costs of the Sentinel program, and as a result, the Pentagon continues to burn billions. Today’s GAO report confirms that we desperately need an independent review to hold Pentagon officials accountable for wasting and mismanaging billions of taxpayer dollars.”
Importance of Test Flights
The Air Force conducts regular unarmed MMIII tests to ensure the fleet’s operational readiness and to signal its capabilities to allies and adversaries. While officials maintain the missile’s performance, a 2023 test was aborted early, resulting in the destruction of a missile due to an „anomaly.” Following this event, House Armed Services Committee Chair Mike Rogers stated that „further life extension is simply infeasible.”
Previous Assessments
A 2021 report by the Federation of American Scientists (FAS) concluded that extending MMIII to 2050 is „technologically feasible,” requiring the replacement of the missile’s solid rocket motors and guidance systems. The FAS report also suggested reducing the missile’s annual testing rate to maintain an adequate inventory of test assets. In 2020, the Defense Secretary granted the Air Force a waiver to conduct fewer annual flight tests to conserve parts, as noted by the GAO.
Challenges of MMIII Extension
If the Air Force proceeds with extending the Minuteman missiles’ operational life beyond its original plan, the GAO found that a „limited parts supply is a risk” to the test flight regimen and that „entire subsystems would need to be replaced to continue meeting operational requirements.”
Questioning the Rationale for Sentinel
Analyst Matt Korda argues that extending the life of the MMIII undermines the original justification for the Sentinel program.
„Now we’re being told that a life-extension campaign was possible all along, meaning that the primary justification for the Sentinel was inaccurate,” Korda, associate director of the Nuclear Information Project at FAS, told Breaking Defense. „So either we’re looking at a deliberate obfuscation to push through an unnecessary weapon system, or a case of multi-billion dollar mismanagement.”
He added, „Either way, everyday Americans will now be forced to pay the price for these skyrocketing costs unless this program gets scaled back.”
Lack of a Flight Testing Plan
Despite delays with Sentinel and the need for continued test flights, the „Air Force has not developed a plan for continued Minuteman III flight testing,” according to the GAO. Before the Pentagon announced the delay for Sentinel last year, the Air Force planned to retire MMIII in 2036, a timeline that is now being revised.
Other Issues with Sentinel
The GAO report identified additional issues with the Sentinel program, including the lack of a risk management plan and the absence of a Sentinel test facility for personnel training. This test facility, a mockup of a Sentinel silo, is planned for construction at Dugway Proving Grounds in Utah.
GAO Recommendations
The GAO issued six recommendations to the Pentagon, including creating a risk management plan, assessing personnel needs for the transition to Sentinel, and developing a strategy for MMIII test launches post-2030. The DoD has concurred with all six recommendations, according to the GAO.
