The US Army has received the first of 19 Sentinel A4 radars being produced under Low-Rate Initial Production (LRIP) 2 by Lockheed Martin. The LRIP phase was approved in August 2023 and will see the Sentinel A4 replace the currently deployed Sentinel A3 radar while integrating with the Army’s Integrated Air and Missile Defense Battle Command System and Indirect Fire Protection Capability.
The delivery follows the successful completion of the first phase of Initial Operational Test and Evaluation, during which the radar was integrated with the Forward Area Air Defense Command and Control system. This milestone advances the program toward full-rate production.
Although many performance details remain classified, the Sentinel A4 is known to provide highly accurate tracking data to the Integrated Battle Command System and FAAD-C2, enabling commanders to rapidly determine engagement options. The radar employs an open-architecture design and a 360-degree gallium nitride-based active electronically scanned array to counter threats ranging from missiles and drones to aircraft, rockets, artillery, and mortars.
Designed for both fixed and maneuver operations, the Sentinel A4 can operate in challenging terrain and contested electromagnetic environments. It is also built to interoperate beyond US Army networks, including with systems such as NASAMS, the Aegis combat system, and NORAD.
