Anduril Industries unveiled its new Steelfin interceptor family on Oct. 12 at the Association of the U.S. Army’s annual meeting in Washington, positioning the modular missiles as a lower-cost alternative to the Patriot’s PAC-3 Missile Segment Enhancement (MSE). The company says it aims to produce Steelfin at roughly one-third the price of a PAC-3 MSE, which costs about $4 million per round, though it has not disclosed a specific unit price.
Steelfin is a two-stage, surface-to-air interceptor family designed to counter cruise missiles, ballistic missiles, hypersonic weapons, and one-way attack drones, according to Anduril. The first stage is a solid rocket booster that can be swapped for different motors; the second stage is a common terminal interceptor sharing airframe, avionics, software, and flight controls across variants. Both hit-to-kill and blast-fragmentation terminal stages will be offered.
“It is an open system, so the ability to fly it with different rocket motors, different seekers, to be able to swap these components out, to be able to reconfigure the system for a range of different threats is a feature that we built into this,” said Christian Brose, Anduril’s president and chief strategy officer, in a preview call with reporters.
Anduril says Steelfin is compatible with existing launchers, including the M903A2 used by Patriot, the U.S. Navy’s Mk 41 Vertical Launch System, the Army’s Typhon launcher, and containerized launchers. It also works with existing fire-control systems such as Aegis and the Army’s Integrated Battle Command System (IBCS).
The company plans to begin flight tests next year. It has completed ballistic testing with representative air vehicles but has not yet flown a Steelfin missile. Steve Milano, Anduril’s senior director of missiles, said he expects full-rate production by the end of 2028 or early 2029, targeting “multiple thousands” of missiles per year on the low end and “closer to hundreds of thousands” per year on the high end, depending on demand from the U.S. and allied customers.
Anduril is competing for the Army’s low-cost interceptor program and was among vendors selected to move forward in the service’s xTech Apex Intercept competition. The company declined to say whether Steelfin was selected for the Army’s separate Future Interceptor program, but Milano said it is a “natural fit” for that effort, which seeks a next-generation PAC-3 MSE replacement with a 7- to 10-inch terminal storage interceptor and a 10- to 13-inch booster.
Most Steelfin subassemblies will be built at Anduril’s Arsenal-1 facility in Ohio, with final integration done with a “handful of partners.” Solid rocket motors will come from Anduril and other companies.
The launch comes as U.S. air defense stocks have been drawn down by combat in the Middle East. This month alone, Raytheon received contracts worth up to $6.3 billion for SM-3 Block IB interceptors and up to $24.4 billion for SM-6 missiles to replenish U.S. Navy inventories, according to Defence Blog.
Sources: Breaking Defense · The War Zone