A minesweeper is a small warship designed to remove or detonate naval mines. Using various mechanisms intended to counter the threat posed by naval mines, minesweepers keep waterways clear for safe shipping.
Technical research ships were used by the United States Navy during the 1960s to gather intelligence by monitoring, recording and analyzing wireless electronic communications of nations in various parts of the world. At the time these ships were active, the mission of the ships was covert and discussion of the true mission was prohibited. The mission of the ships was publicly given as conducting research into atmospheric and communications phenomena. However, the true mission was more or less an open secret and the ships were commonly referred to as "spy ships".
A spy ship or reconnaissance vessel is a dedicated ship intended to gather intelligence, usually by means of sophisticated electronic eavesdropping. In a wider sense, any ship intended to gather information could be considered a spy ship.
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, and a slightly modified version was designated as Type 54A. 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 Shantou-class gunboat was a Chinese-built gunboat of the People's Republic of China's People's Liberation Army Navy. Known in the United States as the "Swatow" class gunboat, it was based on the Soviet P-6 class torpedo boat. The boat is designated as Type 55A. Instead of being wooden hulled, and having torpedoes as the main armament, the Shantou class is steel-hulled, with guns as the main armament. The Shantou is the predecessor of the Type 062 gunboat, or more commonly known as the Shanghai-I & II class.
The Type 062 gunboat is a class of gunboat of the People's Liberation Army Navy first developed and constructed in the 1950s. This unsophisticated class is relatively well-armed for its size and is the most widely built and exported Chinese naval vessel in terms of numbers. A total of 30 were built, initial boats being known as the Shanghai I class and later slightly improved boats being known as the Shanghai II class. The Shanghai I class was slightly smaller than its successor, the Shanghai II class, displacing 125 tons instead of 135 tons, and had a twin Chinese Type 66 57 mm gun mount forward. All other specifications are identical to the Shanghai II class, which replaced the 57 mm with twin 37 mm gun mounts. Some boats remained in active service well into the early 1990s in the PLA navy and longer in the case of the Korean People's Navy.
Naval trawlers are vessels built along the lines of a fishing trawler but fitted out for naval purposes; they were widely used during the First and Second World Wars. Some—known in the Royal Navy as "Admiralty trawlers"— were purpose-built to naval specifications, others adapted from civilian use. Fishing trawlers were particularly suited for many naval requirements because they were robust vessels designed to work heavy trawls in all types of weather, and had large clear working decks. A minesweeper could be created by replacing the trawl with a mine sweep. Adding depth charge racks on the deck, ASDIC sonar below, and a 3-inch (76 mm) or 4-inch (102 mm) gun in the bow equipped the trawler for anti-submarine duties.
ORP Żuraw was a Jaskółka-class minesweeper of the Polish Navy at the outset of World War II. Her name is the Polish word for the common crane. Żuraw participated in the defense of Poland during the German invasion of 1939. The ship was surrendered to the Germans following the Polish capitulation and renamed Oxhöft as a naval trawler. Following the German surrender at the end of the war, the ship was returned to Poland under her old name. In 1947, Żuraw was modified for use as a hydrographical survey ship and renamed Kompas. She was broken up in 1981.
Type 912 degaussing/deperming ship (ADG) is a type of little known auxiliary ships built in the Republic of China (PRC) for the People's Liberation Army Navy (PLAN), and this class has several derivatives. As of 2022, Type 912 is the most numerous degaussing/deperming ship in PLAN, and the longest serving degaussing/deperming ships in PLAN, until its successor ype 911 finally begun to appear in early 2010s.
Type 210 icebreaker with NATO reporting name Yanbing (延冰) class is the second generation icebreaker indigenously developed by China for the People's Liberation Army Navy (PLAN) to replace Type 071/071A/071G Yanha class icebreakers, and itself has since been replaced by Chinese third generation Type 272 Yanrao class icebreaker.
Type 645 oceanographic research ship is an oceanographic ship developed by China for the People's Liberation Army Navy (PLAN) and other Chinese civilian establishments. Type 645 was an experimental program of the Fourth five-year plan of China and designed by the 2nd Directorate of 708th Institute of China State Shipbuilding Corporation, which is also more commonly known as China Shipbuilding and Oceanic Engineering Design Academy (中国船舶及海洋工程设计研究) nowadays. Construction begun in October 1977 and the ship was launched in October 1978, entering service with PLAN in December 1978. There are a total of twelve laboratories on board totaling 257 square meters. Deployment proved that the design was successful, and three more units were built for civilian use, named as Xiangyanghong 9, Xiangyanghong 14 and Xiangyanghong 16 respectively. However, on May 2, 1993, Xiangyanghong 16 was rammed and sunk by a Cypriot LNG carrier more than nine time of its size in the East China Sea near Jeju Island, with the loss of three crew members. The sister ships in civilian service are often tasked with military and paramilitary missions and thus frequently come under PLAN and Chinese Coast Guard control.
Type 646 hydrographic survey ship with NATO reporting name Kanyang classis a type of survey vessel currently in service with the People's Liberation Army Navy (PLAN).
Type 635 hydrographic survey ship is a series of hydrographic survey ships developed by China for its People's Liberation Army Navy (PLAN). More successful than Type 625 of the same era, Type 635 still remains active in PLAN after half a century of service, even after its successor Type 636 has entered service. Type 635 series in PLAN service are designated by a combination of two Chinese characters followed by three-digit number. The second Chinese character is Ce (测), meaning survey in Chinese, because these ships are classified as survey ship. The first Chinese character denotes which fleet the ship is service with, with East for East Sea Fleet, North for North Sea Fleet, and South for South Sea Fleet. However, pennant numbers may have changed due to the change of Chinese naval ships naming convention.
Type 8105 naval trawler is a Chinese auxiliary ship of the People's Liberation Army Navy (PLAN).Type 8105 along with Type 792 and Type 8154 naval trawlers have all received NATO reporting name FT-14 AIT class,meaning Fishing Trawler - 14 Auxiliary Intelligence-gathering Trawler. After retiring from their original role of a spy ship, Type 8105 naval trawlers have been converted to auxiliary minesweepers and survey vessels, and kept in operational reserve of the Chinese navy.
Yuzhou USVs are various USV developed by Chinese Zhuhai Yunzhou Intelligence Science & Technology Corporation (云洲智能科技), most of which have already entered service with Chinese military, paramilitary, police & governmental agencies:
Type 917 torpedo retriever (TR/TWR) / range support vessel / target ship is a type of little known auxiliary ship built in the People's Republic of China (PRC) for the People's Liberation Army Navy (PLAN).As a successor of earlier Type 803 torpedo retriever, Type 917 TR/TWR/AGT has received NATO reporting name Damen class, or 大门 in Chinese, meaning "big gate". As with its predecessors, once these have retired from their original torpedo retrieving duties, they are converted to range support vessels/target ships,until finally sunk as targets. Specification:
Ostar unmanned vehicles are uncrewed vehicles. They are developed in the People's Republic of China (PRC) by Ostar, most of which are in service with various Chinese governmental agencies/departments, and government-owned enterprises.
THLMT unmanned underwater vehicles (UUV)s are uncrewed vehicles developed in the People's Republic of China (PRC) by Tianjin Hanhai Lanfan Marine Technology Co. Ltd (天津瀚海蓝帆海洋科技有限公司), most of which are in service with various Chinese governmental agencies/departments, and government-owned enterprises.
Deepinfar unmanned underwater vehicles (UUV)s are uncrewed vehicles developed in the People's Republic of China (PRC) by Deepinfar, most of which are in service with various Chinese governmental agencies/departments, and government-owned enterprises.
People's Liberation Army Navy 
