The US Army has taken delivery of the first Sentinel A4 radar under Low-Rate Initial Production 2, part of a planned batch of 19 systems being built by Lockheed Martin. The LRIP phase, authorized in August 2023, is intended to transition the Army from the Sentinel A3 to the more capable Sentinel A4, while integrating the radar into the Integrated Air and Missile Defense Battle Command System and Indirect Fire Protection Capability.
This delivery follows completion of the first phase of Initial Operational Test and Evaluation, which demonstrated successful integration with the Forward Area Air Defense Command and Control system. The milestone brings the Sentinel A4 program closer to full-rate production.
Although many of the radar’s capabilities remain classified, it is known to provide high-fidelity tracking data to IBCS and FAAD-C2, supporting rapid command decisions on threat engagement. The radar uses an open-architecture design and a 360-degree gallium nitride AESA sensor to counter a broad spectrum of threats, including missiles, drones, aircraft, helicopters, rockets, artillery, and mortars.
Designed for flexibility, the Sentinel A4 can be employed from fixed positions or move with maneuver units and is optimized for operation in rugged terrain and contested electromagnetic environments. It is also capable of interfacing with non-Army systems such as NASAMS, the Aegis combat management system, and NORAD.
