The Yuanwang-class (远望; meaning "Long View") are used for tracking and support of satellite and intercontinental ballistic missiles by the People's Liberation Army Navy (PLAN) of the People's Republic of China (PRC). The detailed specifications of the ships are not released by the PLAN. They are thought to have a displacement tonnage of around 21,000 Long ton when fully loaded, with a crew of about 470 and a length of about 190 meters (620 ft). Their propulsion is from one Sulzer Ltd. diesel engine, with a top speed of 20 knots (37 km/h).