The Huangpu-class gunboat were gunboats of the People's Republic of China's People's Liberation Army Navy, with production first begun at Jiangnan Shipyard on January 20, 1953, after request was submitted in October 1952.. These boats were designated as Type 53A (53 Jia Xing, 53甲型), and a slightly modified version was designated as Type 54A (54 Jia Xing, 54甲型). They entered service in the 1950s and had been completely taken out of active service by the early 2000s and were transferred to law enforcement agencies. However, just like the Shantou, Beihai and Yulin classes that were transferred for law enforcement adaptation, these obsolete and aging boats are not satisfactory in their new roles due to their low maximum speed, sometime as low as 10 knots, which was not fast enough to catch the smugglers’ high speed motorboats. As a result, these boats were subsequently transferred again, this time to reserves, subordinated to naval militia in various Military Maritime Districts in China as training boats and port security / patrol boats within the confines of the harbors. The new design incorporated a low superstructure fore and aft, providing additional accommodations for police or troops. A lightly armed version with 25 mm main guns received NATO reporting name Beihai class. This advantage combined with their later completion time in comparison to Shantou, Beihai and Yulin classes have made this class more active in the reserve than the others in the naval militia, However, like the Shantou, Beihai and Yulin classes, as the new class of port security patrol boats entering service, the Huangpu class is increasingly being converted, mothballed and eventually scrapped. Just like the Shantou, Beihai and Yulin classes, many of the surviving units are being converted to naval range support boats and target drones and thus reactivated into active service as minor support auxiliaries. It can be either used as a target control boat to remotely control the converted drones, or as a drone itself. When the drone is in operation, the crew departs the boat. Most of the range support boats in the PLAN also shoulder the responsibility of inshore surveying and these converted boats are no exceptions, despite the little scientific instruments they carried. The reason is that originally, majority of the hydrographic surveys were conducted by civilian fishing vessels with the additional scientific equipment, naval and governmental crews on board. However, since the Chinese economic reform and the