- Lockheed Martin received a $233 million contract to supply IRST21 Block II infrared tracking systems to the U.S. Navy and Air National Guard.
- The Block II variant includes upgraded optics, processors, and algorithms to enhance long-range, passive target detection.
Lockheed Martin has secured a $233 million contract to deliver its IRST21 Block II infrared search and track systems, along with initial spares, to the U.S. Navy and Air National Guard.
The award supports deployment across multiple fighter platforms and follows the Navy’s recent declaration of Initial Operational Capability for the sensor.
The IRST21 Block II is Lockheed Martin’s next-generation passive infrared tracking system designed to detect and track airborne threats at extended distances without emitting a radar signal.
According to the company, the system enhances situational awareness and accelerates targeting timelines for warfighters facing complex airspace threats.
In a statement, Lockheed Martin described IRST21 as a long-wave infrared system that “passively detects and tracks airborne targets at extended ranges.” The company says the Block II variant features updated optics, advanced processors, and algorithms aimed at supporting engagements beyond visual range.
The contract comes shortly after the U.S. Navy cleared IRST21 Block II for full-rate production. That decision was enabled by the service’s formal declaration of Initial Operational Capability for the system, which Lockheed Martin said now paves the way for broader fleet deployment.
“IRST21 Block II delivers a game-changing leap in passive warfighting capabilities across multiple platforms,” said Cristin Stengel, IRST21 program director for Lockheed Martin. “By significantly enhancing the range and accuracy to enable weapon employment in challenging environments, this system ensures pilots remain ahead of evolving adversaries and mission-ready at all times.”
The IRST21 Block II is designed to function across fourth-generation aircraft platforms, including the Navy’s F/A-18E/F Super Hornet and the Air Force’s F-15 and F-16 fighter fleets. On the Super Hornet, it is mounted on the nose of the centerline fuel tank, where it operates in coordination with the aircraft’s AN/APG-79 radar. This allows the platform to remain effective even in environments where radar is denied or heavily contested by electronic warfare systems.
For legacy fighters like the F-15 and F-16, the IRST21 is integrated into the Legion Pod—a modular, externally mounted system designed to rapidly deliver advanced targeting functionality without requiring major structural changes. Lockheed Martin says the pod-based design offers transportability and scalability, extending sixth-generation targeting capabilities to current airframes.
One of the system’s key features is its passive operation. Unlike radar systems that emit signals and can be detected or jammed, IRST21 operates silently, making it more survivable in complex threat environments. Company officials emphasize that this aspect is critical in modern combat scenarios, where the ability to detect without being detected can shape the outcome of air engagements.
Lockheed Martin says the system is engineered for sustained performance across missions where quick reaction time, sensor fusion, and reduced signal exposure are priorities. The company has previously highlighted IRST21’s role in enabling coordinated, multi-domain operations by giving pilots early detection and tracking capabilities that are independent of radar.

