The ''Cheonghaejin''-class ASR (
Hangul
The Korean alphabet, known as Hangul, . Hangul may also be written as following South Korea's standard Romanization. ( ) in South Korea and Chosŏn'gŭl in North Korea, is the modern official writing system for the Korean language. The le ...
: ;
Hanja
Hanja (Hangul: ; Hanja: , ), alternatively known as Hancha, are Chinese characters () used in the writing of Korean. Hanja was used as early as the Gojoseon period, the first ever Korean kingdom.
(, ) refers to Sino-Korean vocabulary, ...
: ) is a
submarine rescue ship class of the
Republic of Korea Navy
The Republic of Korea Navy (ROKN; ko, 대한민국 해군), also known as the ROK Navy or South Korean Navy, is the naval warfare service branch of the South Korean armed forces, responsible for naval and amphibious operations. The ROK Navy i ...
. Only one ship has been built in her class, ROKS ''Cheonghaejin'' (ASR 21), in 1995. Its operations include rescuing trapped sailors in submarines, naval operation support for submarines, underwater research and mapping support, and recovery of sunk vessels. It is equipped with a
deep submergence rescue vehicle
A deep-submergence rescue vehicle (DSRV) is a type of deep-submergence vehicle used for rescue of downed submarines and clandestine missions. While DSRV is the term most often used by the United States Navy, other nations have different design ...
(DSRV) that operates up to , and a rescue chamber that holds up to nine people.
Once all nine
''Son Wonil''-class submarines are delivered to the Republic of Korea Navy, another ASR ship of the same class is planned to be built.
*Notable operations
**salvaged a North Korean submarine in 1998
**salvaged #357 that was sunk during the
naval clash in 2002 with North Korea
![ROKS Cheonghaejin (ASR 21)](https://upload.wikimedia.org/wikipedia/commons/6/66/ROKS_Cheonghaejin_%28ASR_21%29.jpg)
{{Republic of Korea Navy ships
Auxiliary ships of the Republic of Korea Navy
Submarine rescue ships
Auxiliary search and rescue ship classes