Gumdoksuri-class patrol vessel

 Gumdoksuri class patrol vessel (Hangul: 검독수리급 고속함) also known as PKG class patrol vessel is a patrol ship of the Republic of Korea Navy. Two variants are planned. The first being PKG-A or  Yun Youngha class missile patrol ship (Hangul: 윤영하급 고속함), and the second being PKG-B class patrol boat.

Development
The Republic of Korea Navy began development of the PKG class in 2003 after a Chamsuri class (PKM class) patrol boat was sunk during a naval clash with North Korean patrol boats on June 29, 2002. The codenamed PKX (Patrol Killer eXperimental) program is the patrol boat modernization project of the ROK Navy.

The PKX consist of two main designs. The larger, missile armed PKG-A of approximately 500 tons and the smaller gun armed PKG-B of approximately 200 tons. PKG-A is planned to take up some of the operations done by Pohang class corvettes, and the PKG-B is planned to replace the aging Chamsuri-class patrol vessel fleet.

The first PKG-A vessel were ordered from Hanjin Heavy Industries. The lead ship of the class, Yoon Youngha (PKG 711), named after Lieutenant Commander Yoon Youngha who was killed during the second battle of Yeonpyeong, was launched on June 28, 2007 and commissioned on December 17, 2008. The production of the PKG-A are being divided between Hanjin Heavy Industries and STX in lots of four.