Chinese sonar trials ship Beidiao 993
Beidiao 993 is an experimental ship chartered by the Chinese People's Liberation Army Navy, and operated by the 760th Research Institute of China Shipbuilding Industry Corporation. Beidiao 993 is specifically designed to carry out experiments of acoustic equipment, such as sonar, and its crew is often composed both naval and civilian staff. Constructed by the Tongfang Jiangxin Shipbuilding Company in Jiangxi, trials begun in December 2000 in Dalian and the ship entered service in the same month. The name Beidiao means North Investigation.