On April 28, South Korea announced that it had completed delivery of the Cheongung (Block I) medium-range surface-to-air missile system to the ROK Air Force. Also known as the KM-SAM, the system reached initial operating capability in 2011 and was first deployed in 2015. The KM-SAM can reportedly range up to 40 km with an altitude ceiling between 15-20 km. It is slated to replace South Korea’s MIM-23 Hawk SAM air defense systems.