The THAAD System the US Is Considering for Additional Deployment

[Monthly Defense Times Editor-in-Chief An Seung-beom] THAAD (Terminal High Altitude Area Defense) is a terminal high-altitude missile defense system. The 'T' in THAAD, Terminal, refers to the terminal flight phase of a ballistic missile, which means re-entry into the atmosphere. Since the practical boundary of the atmosphere is at an altitude of 100 km, THAAD is designed to intercept ballistic missiles re-entering the atmosphere at altitudes up to 150 km.

Because the engagement altitude is high (40 km to 150 km), the air density is low, making it impossible to control the missile's flight with aerodynamic fins. Instead of aerodynamic fins, THAAD's missile integrates an orbit correction and control system that controls the missile's attitude with lateral thrust independent of the main thrust. Also, since the engagement altitude is at the ionosphere level, ionospheric scattering occurs, which disrupts radar signals like those used by Patriot system missiles. Therefore, THAAD uses infrared sensors instead of radar sensors to detect and track targets. Infrared sensors have the advantage of providing more precise tracking angles than radar sensors.

In South Korea, one battery of the U.S. Army's THAAD is deployed in Seongju, Gyeongsangbuk-do. One THAAD battery consists of a fire control center, a fire control radar (AN/TPY-2), and six launchers. This is similar to one Patriot system battery, which consists of an Engagement Control Station (ECS), a fire control radar (AN/MPQ-53 or AN/MPQ-65), and six launchers. However, while one Patriot launcher can carry up to four missiles, one THAAD launcher carries eight missile canisters (4 x 2), which is a key difference.

In other words, one THAAD battery maintains a posture capable of launching up to 48 missiles (8 x 6). Since THAAD is a critical strategic asset for intercepting ballistic missiles, its fire control radar must not be disabled by enemy electronic jamming. For this reason, the AN/TPY-2 fire control radar system of THAAD is a high-power large AESA radar using more than 20,000 elements, designed to make it difficult for the enemy to jam its signals. The AN/TPY-2 radars deployed in Japan are located in Kyogamisaki and Shariki, where they operate as ballistic missile early warning systems rather than fire control radars. In contrast, the AN/TPY-2 radar deployed in South Korea is assigned to an engagement unit (the U.S. Army 2nd Air Defense Artillery Regiment Delta Battery) and operates as a fire control radar.

Thus, in South Korea, the Republic of Korea Air Force’s Green Pine radar operates as a ballistic missile early warning radar, while the THAAD battery’s AN/TPY-2 radar operates as a high-altitude ballistic missile interception fire control radar. Unlike the Patriot system, which intercepts both ballistic missiles and aircraft and integrates IFF (Identification Friend or Foe) systems into its radar set for aircraft identification, THAAD intercepts only ballistic missiles and therefore the AN/TPY-2 radar does not have an IFF device.

This content was produced with the assistance of AI translation services.