Several recent tests of the Air Force’s land-based, LGM-35A Sentinel intercontinental ballistic missile at Naval Air Weapons Station China Lake, Calif., reflect “significant progress” in the weapon’s engineering, manufacturing and development phase, missile prime Northrop Grumman said Tuesday.
“Forward and aft sections of a Sentinel ICBM [intercontinental ballistic missile ] missile were evaluated through a rigorous test campaign at the company’s Strategic Missile Test and Production Complex in Promontory, Utah,” the company said in a press release. “The tests lower risk for the program with important data about the missile’s inflight structural dynamics. Data from the tests help engineering teams mature models, lower risk and ensure flight success.”
Sarah Willoughby, Northrop Grumman’s vice president and program manager of Sentinel, said the “shroud fly-off test proved our modeling predictions are solid, while the missile stack test demonstrated inflight missile performance, helping validate assumptions and fine-tune models.”
Beside the most recent test, Northrop Grumman announced a stage-two solid rocket motor static fire test in January, a stage-one solid rocket motor static fire test a little less than a year ago and a hypersonic wind tunnel test about a year ago.
At the Exchange Monitor’s annual Nuclear Deterrence Summit in February, Air Force Gen. Anthony Cotton, the head of U.S. Strategic Command, has said that his entire portfolio is under review.
The Air Force has informed Congress of a 37% unit cost Nunn-McCurdy program breach on Sentinel, an increase in unit cost per missile to $162 million from $118 million in 2020 due to unpredicted military construction costs in what will be a massive civil works project to build Sentinel silos and roads able to accommodate missile transportation.
The total Sentinel program cost estimate is now more than $125 billion compared to more than $95 billion earlier.
Asked at the summit why he thought estimates for military construction costs for Sentinel fell far short and how to prevent such oversights in the future, Cotton replied, “I don’t know. I wish I knew the answer to that because, not only when it comes to Sentinel, but when it comes to all the modernization within my purview, all of that has to be taken into consideration.”
The pits, the fissile cores of nuclear-weapon first stages, are designed by the Lawrence Livermore National Laboratory in California for the W87-1 warheads that Sentinel will eventually carry. The first Sentinels will use existing W87 warheads from the fleet of Minuteman III ICBMs that the new missiles will replace starting around 2030.
A version of this story first appeared in Weapons Complex Morning Briefing affiliate publication Defense Daily.
