Sentinel A4 Is the World’s Premier Air and Missile Defense Radar.

Sentinel A4 is a high-performance replacement of the legacy Sentinel A3 (AN/MPQ-64A3) air and missile defense radar that will provide significant improvements to the existing Sentinel capability against cruise missiles, unmanned aerial systems, rotary wing and fixed wing threats. The Sentinel A4 will add the ability to detect Rocket, Artillery, and Mortar (RAM) threats, providing RAM Point of Origin and Point of Impact locations, while also providing added protection against electronic threats.

Working with Integrated Air Defense Systems & Command & Control

Sentinel A4 can be easily integrated with existing defense systems, not only IFPC and NCR-IADS, but also with systems like NASAMS, the Aegis Combat Management System and NORAD, to name a few.

Integrates with Army’s current IBCS and FAADC2
Provides data to C2 systems to leverage critical information to determine the best course of action to address threats
IBCS will “talk” to the Army’s IFPC Increment 2, and as the primary sensor for IFPC, Sentinel A4 will be integral in supporting critical asset protection.

Flexibility and Connectivity When it’s Needed Most

Sentinel A4 provides the most current technology for short to medium-range air & missile defense.

Built with an open architecture, the Sentinel A4 adapts to challenging environments, which protects the soldier and supports the uninterrupted execution of the mission.
Can grow to increase capability using software-defined design to instantaneously combat a changing threat landscape – all without changing hardware or physically changing modes on the radar.
No other system in production can match its capability, adaptability or connectivity.

First Sentinel A4 Radars Delivered Ahead of Schedule

Sentinel A4 Capability Brochure

Delivering Transformative Capability

Sentinel A4 wastes no time bringing enhanced capability to the battlefield and homeland defense. Sentinel A4 leverages years of expertise and technology and provides an all-new platform that sees further and satisfies multiple missions simultaneously, including air defense and engagement support for point defense. The level to which it can perform simultaneous functions is unique to Lockheed Martin and Sentinel A4, ultimately providing the best-possible level of protection for the men and women who rely on it.

Sentinel A4 detects and tracks cruise missiles, fixed-wing adversary aircraft, helicopters and unmanned aircraft systems (UAS) – even rockets, artillery and mortar threats – precisely calculating the Point of Impact, which is imperative to protecting critical assets and those on the ground. Sentinel A4 provides both 360 degree and stop-and-stare capability, from the ground to zenith, with no cone of silence, while providing Fire Control Quality Track Data.
It does this through a digital Active Electronically Scanned Array (AESA) architecture that delivers greater than a 75% increase in range over the legacy system and full hemispheric coverage.
Sentinel A4 leverages gallium nitride, or GaN, which Lockheed Martin has been delivering in its radars since 2015, and is the standard in today’s capability sets, providing increased range, power efficiency and reliability to the warfighter.
The system also provides improved electronic protection. This translates to increased survivability on the battlefield. Because the system is adaptable in nature, users can “set it and forget it,” meaning the radar will meet all requirements without needing manual inputs or adjustments.
Sentinel A4 delivers enhanced combat identification (CID) for reduced engagement timelines. The improved CID supports the overall asset protection capability, while simultaneously performing the full search & track mission.
Sentinel A4 is mobile in its truest form. It can be operated from a fixed position or be transported by air, sea, helicopter, rail or organic off-road means to ensure protection wherever the mission calls. Applications like the NCR-IADS require this capability, and Sentinel A4 delivers.

All this high-level performance comes regardless of other external factors – including harsh environmental conditions, complex terrain, and contested environments involving jamming and electronic warfare – something unrivaled in the field.

Proven Performance & Commonality

We’ve continuously built on our successes and experience, growing our proven track record of high-performance radar systems. Our radars are designed with commonality across the portfolio, leveraging decades of performance, design enhancements, and end user feedback. As an example, we’re able to leverage commonality with battlefield superstars like the Q-53 radar, which has maintained >95% operability during its entire career. Lockheed Martin just delivered our 189th Q-53 system and counting. It is still fielded with the highest confidence for the U.S. Army today. In fact, these Q-53 radars are so reliable and modular that the Army has deemed the digitization (DDREX) of Q-53 a "key enabler" of their modernization strategy.

Ready for the Real World, Today

Sentinel A4 provides benefits across the spectrum of considerations, whether it’s exceptional capabilities, high availability, flexible mission performance, growth potential, or system integration. Lockheed Martin has already delivered the first five radars, with an additional five more on the horizon. Sentinel A4 isn’t just an upgrade, it’s a transformational change. The capability is needed. In a mission space where lives depend on it, Sentinel A4 delivers.