Artist’s rendition of the LGM-35A Sentinel intercontinental ballistic missile. (Image: Northrop Grumman)

WASHINGTON — While the Air Force struggles to construct a plan to cut back the Sentinel program’s skyrocketing costs, work has not stopped in the development of the new ICBM to replace the service’s aging arsenal of Minuteman III missiles, according to the service’s nuclear policy guru.

“[W]ork can still continue under the contract that exists today. So, we don’t want to slow down, come to a full stop on the program, but there does need to be a restructure to get after the cost growth has happened,” Lt. Gen Andrew J. Gebara, deputy chief of staff for Strategic Deterrence and Nuclear Integration, told the Mitchell Institute today.

“I was on the Hill multiple days last week as part of our team where [Air Force acquisition head William] LaPlante described the challenges that we’ve had and described his decision to certify. No one was happy with cost growth, and I think that absolutely in the Air Force, we’re not happy with that either. So, we do need to think about ways to get after that, but I don’t think we should think of it as a full stop to the program until we can get to a new Milestone B; so, there will be continued steps taken,” he added.

In particular, Gebara stressed that work on the Sentinel missile itself by prime contractor Northrop Grumman has been proceeding fairly well.

“It is important to remember the program that stage one, two and three of the missile have been successfully test fired already. I’m not going to say that retired every risk on the missile. But largely the issues of the missile are known issues that can be worked, and are largely okay,” he said.

The problems, he reiterated, surround the sprawling infrastructure requirements for Sentinel’s ground segment.

Sentinel has seen exploding costs related to those command and launch facilities, with Defense Department officials most recently estimating the program’s price tag could reach $141 billion unless significant changes are made. The cost projections broke the congressionally mandated tripwire, known as Nunn-McCurdy, for a high-level Pentagon review of whether a program should be cancelled — the upshot being LaPlant’s decision to certify Sentinel to continue, but to block its Milestone B decision pending a restructure to reduce costs.

Milestone B sets a program’s design in budgetary and scheduling stone by authorizing contractors to proceed with engineering and manufacturing development.

Gebara said there are two major components to the Air Force’s plan of action following that decision: “to ensure Minuteman III sustainment [is] unbroken;” and “roll up our sleeves” to “figure out the best program to get to a Milestone B decision of the future.”

While the Air Force now as “good funding” to support Minuteman III upkeep, there are “unknown unknowns” that may crop up due to the simple fact that those ICBMs are already well beyond their design lifetimes.

“I can show you charts and budget lines and the like that gets after every one of the challenges we see in Minuteman to keep it relevant, but we can only program and plan to what we can, what we know is going on and what we can predict is going on,” he said. “And and as we go to the right … there’s always the chance of an unknown unknown, and a lot of our suppliers don’t provide parts for these kind of systems anymore, so it’s long lead times to try and get these systems logistically taken care of.”

Despite the concerns, Gebara stressed that the “Air Force is absolutely committed to making sure Minuteman is sustained” no matter what it takes, and has made that pledge toCongress.

“If unknown unknowns happen on Minuteman, we will get after that and make sure that that’s covered until such time as Sentinel stands alert,” he said.