The U.S. Space Force this week issued a solicitation to sustain systems for the Raytheon Technologies [RTX] AN/FPS-108 Cobra Dane radar.

The chosen contractor will provide life-cycle management of systems for Cobra Dane, a ground-based missile defense and space situational awareness radar at Eareckson Air Station in Shemya, Alaska.

Cobra Dane “was operationally fielded in 1977 and later underwent a major system modernization program that was completed in 1993,” Space Force said, adding that the radar “is undergoing a number of modernization and mini service life extension program (SLEP) efforts” for its missions, which also comprise cataloging near-earth orbiting satellites, including space debris, and providing early observation of “new foreign launches.”

Space Force has said that Cobra Dane operations may last until 2030 and that the $1.6 billion Space Fence radar system by Lockheed Martin [LMT] is to take on many of Cobra Dane’s roles. Located on Kwajalein Atoll in the Marshall Islands, the solid-state S-band Space Fence radar system achieved initial operational capability on March 27, 2020.

Cobra Dane’s “mission equipment and associated sustainment suites consist of a mix of unique, custom-built components that are increasingly difficult to maintain on a 45-year-old radar due to non-availability of replacement parts,” Space Force said last year. “Subsystems are no longer supported by the original equipment manufacturers. In addition, transmitter groups, traveling wave tubes, time delay units and all associated components and spares require replacement. Due to the limited demand rates for spares, and indefinite system lifespan, life-of-type buys may be required to support this weapon system. Without these replacements, there is a high risk that equipment failures will cause unacceptable mission downtime. Funding may be used to address Diminishing Manufacturing Sources (DMS) issues.”

Sen. Dan Sullivan (R-Alaska) has pushed for extending the life of Cobra Dane, as the Pentagon considers radar modernization options for countering Russian and Chinese hypersonic missiles.