Anduril Industries has unveiled Steelfin, a configurable family of surface-to-air interceptor missiles designed to address ballistic, cruise, hypersonic and lower-cost drone threats. The US military is the principal prospective customer, including the Army’s Future Interceptor programme. Flight testing is planned for 2027, while much of the subassembly work is expected to take place at Anduril’s Arsenal-1 facility in Ohio.
Steelfin uses a common two-stage architecture. A selectable first-stage booster is intended to provide different ranges, performance levels and launch configurations, while a shared terminal-interceptor stage uses common airframe, avionics, software and flight-control elements. The upper stage can be fitted with different sensors, including radar and infrared seekers, and is designed to work with existing launchers and software. Reported compatibility includes Patriot, CAML and other launcher configurations.
Anduril has completed ballistic testing with representative air vehicles and plans to manufacture variants on a common production line. The company is targeting several thousand interceptors annually in the near term, with full-rate production potentially beginning in late 2028 or early 2029. Planned booster diameters include 10, 18 and 21 inches; the smallest variant appears aimed at the Army requirement between Patriot PAC-3 MSE and a THAAD-related interceptor. Anduril is targeting a price of about one-third of a Patriot PAC-3 MSE, although no final unit price, firm orders or operational deployment date has been disclosed.