The United States has awarded Lockheed Martin a $328.5 million Foreign Military Sales (FMS) contract to supply Taiwan’s Air Force with advanced Legion-ES IRST21 infrared sensor systems.
Under the agreement, Lockheed Martin will manufacture long-wave infrared search-and-track (IRST21) systems capable of passively detecting and tracking airborne threats at extended distances. Designed for integration with Taiwan’s F-16 fighter fleet, the sensors operate without emitting radar signals, improving survivability while providing pilots with earlier threat awareness.
This deal represents the first international deployment of the Legion-ES configuration, underscoring the growing depth of defense cooperation between Washington and Taipei.
Contract work will be carried out in Orlando, Florida, and is scheduled to continue through mid-2031. More than $157 million in FMS funding had already been obligated at the time of contract award.
The IRST21 system builds on Lockheed Martin’s extensive infrared tracking heritage, which has logged over 300,000 flight hours, and is viewed as a significant force multiplier for Taiwan’s air combat capability amid increasingly complex regional air defense challenges.
Since 2023, US defense sales to Taiwan have expanded significantly. In December 2025, Washington notified Congress of a landmark $11.1 billion arms package that included 82 HIMARS launchers, 60 M109A7 self-propelled howitzers, ALTIUS loitering munitions, Javelin and TOW missiles, and tactical mission network systems.
Earlier, in November 2025, a separate $330 million FMS notification covered non-standard spares and repair support for Taiwan’s F-16, C-130, and Indigenous Defense Fighter fleets. In October 2024, the US also approved the sale of three NASAMS air defense batteries with 123 AMRAAM-ER missiles, deliveries of which are expected to continue through late 2025.
