Lockheed Martin has delivered the first Sentinel A4 radar to the US Army as part of the service’s low-rate initial production 2 program, which includes a total of 19 systems. The delivery represents a major step forward in enhancing the Army’s air and missile defense network amid growing threats from missiles, unmanned systems, and indirect fire weapons.
The LRIP 2 decision, approved in August 2023, will see the Sentinel A4 replace the legacy Sentinel A3 radar currently in service. Designed for full integration with the Army’s Integrated Air and Missile Defense Battle Command System and Indirect Fire Protection Capability, the radar strengthens command-and-control connectivity across the service’s air defense formations.
This milestone follows the completion of the first phase of Initial Operational Test and Evaluation, during which the Sentinel A4 was successfully integrated with the Forward Area Air Defense Command and Control system. The progress moves the program closer to full-rate production while validating the radar’s ability to deliver precise tracking data that supports rapid engagement decisions. Although many technical details remain classified, the system is designed to enhance situational awareness across complex battlespaces.
Equipped with a 360-degree GaN-based active electronically scanned array and an open-architecture design, the Sentinel A4 can detect and track missiles, drones, aircraft, helicopters, rockets, artillery, and mortars. The radar is deployable in both fixed and mobile configurations, optimized for operations in rugged terrain and electronically contested environments. It is also built to interface beyond Army networks, including with NASAMS, the Aegis combat management system, and NORAD, expanding its role within joint and allied defense operations.
