Cheonji-class fast combat support ship

After the Korean War, the Korean Navy purchased and operated small refueling ships from the 1960s to the 1980s. These ships were obsolete due to prolonged operation, which forced their retirement beginning in the late 1970s. As the demand for maritime operations increased day, the Navy required vessels to complete the missions.[1][5]

From the mid-1980s, based on ship drying experiences, the Korean Navy proposed building combat support ships domestically. From 1988 to 1990, the first combat support ship, later named Cheonji, was built and launched.[5] Daecheong and Hwacheon were built seven years later. At the time, the Korean Navy decided whether or not to build follow-up ships after finishing the operation test of the first ship.[1]

As the needs of support ships increased, the Navy designed the Soyang-class ships in 2016, based on the Cheonji class.[1]

Cheonji-class ships are about 133 metres (436 ft 4 in) long, 18 metres (59 ft 1 in) wide. It was the largest of the Korean Navy before the construction of Dokdo class.[5][4] They can load about 4,800 tons of cargo, excluding the ship's supply.[1]

They are armed with one 20 millimetres (0.79 in) gun, one 40 millimetres (1.6 in) gun, and Device Automatic Gurre Anti-missile Infrared Electromagnetic device, providing self-defence against enemy ships.[1]

Resupply systems are located both left and right, to supply two ships at once. At the stern, it is possible to resupply both Cheonji class and other ships by using UH-60 Black Hawk helicopters.[4] The most distinctive feature is that it is highly adaptable and can transport supplies to ports without cargo handling facilities.[6]

The names of fast combat support ships are taken from lakes that have large water volume in Korea.[2] For example, Cheonji, the first ship of the class, is the name of Cheonji lake.