Type 646 hydrographic survey ship with NATO reporting name Kanyang (勘洋, meaning Surveying Oceans) class is a type of survey vessel currently in service with the People's Liberation Army Navy (PLAN). Type 646 Kanyang class survey ship is designed by the 4th Directorate of the 708th Institute of

China State Shipbuilding Corporation The China State Shipbuilding Corporation (CSSC) is a Chinese shipbuilding conglomerate. Description CSSC is one of the top 10 defence groups in China. It consists of various shipyards, equipment manufacturers, research institutes and shipbu ...

(CSSC), which is also more commonly known a
China Shipbuilding and Oceanic Engineering Design Academy (中国船舶及海洋工程设计研究)
nowadays. Construction of both ships begun simultaneously in December 1978 and both were launched in 1982, and both entered service with PLAN

South Sea Fleet The Southern Theater Command Navy (), or the South Sea Fleet (SSF; ) is one of the three fleets of the Chinese People's Liberation Army Navy, operating in the South China Sea under the Southern Theater Command. It is headquartered in Zhanjiang, ...

in 1978. In comparison to earlier shps converted from fishing and cargo vessels, these purposely designed ships carried more equipment and greatly improved efficiency. These ships are named as Nan-Ce (南测, meaning South Survey), followed by a three digit number. South means

and Survey means that these ships are survey vessels. Specification:Type 646
/ref> *Length (m): 60 *Displacement (t): 676 *Speed (kt): 15.51 *Survey speed (kt): 3 – 4

References

{{Ship classes of the Chinese Navy, state=uncollapsed Auxiliary ships of the People's Liberation Army Navy