Lockheed Martin has secured a $328.5 million FMS contract from the US government to deliver Legion-ES IRST21 sensor systems for Taiwan’s fighter aircraft.
The contract calls for the production of long-wave infrared search-and-track sensors designed to passively identify and track aerial targets at long ranges. Intended for Taiwan’s F-16 fleet, the IRST21 system operates without active radar emissions, reducing detectability while improving early threat detection for aircrews.
Notably, this marks the first time the Legion-ES variant will be supplied to an allied nation, highlighting a new level of technology sharing between the United States and Taiwan.
Manufacturing and integration work will take place in Orlando, Florida, with contract completion expected by mid-2031. At award, more than $157 million had already been committed under the FMS program.
Lockheed Martin’s IRST21 sensors draw on decades of infrared tracking development and operational use, with a cumulative record exceeding 300,000 flight hours. The system is expected to significantly enhance Taiwan’s air combat effectiveness amid evolving regional security dynamics.
The award comes amid a broader expansion of US defense support to Taiwan. In December 2025, the US announced an $11.1 billion arms notification featuring HIMARS rocket artillery, self-propelled howitzers, unmanned systems, anti-tank missiles, and advanced mission networking tools.
This followed a $330 million notification in November 2025 for spare parts and sustainment support across multiple Taiwanese aircraft fleets. Earlier, in October 2024, Washington approved the sale of NASAMS medium-range air defense systems equipped with AMRAAM-ER missiles, further strengthening Taiwan’s layered air defense posture.
