source China Defense Blog
October 20, 2011: STRATEGY PAGE
China has completed two more Wozang class minesweepers. These 550 ton ships have a non-metallic hull and modifications to its engines and electrical gear to reduce noise and magnetic emissions. This reduces vulnerability to multi-sensor naval mines. The two latest Wozangs have improved minehunting gear and a new 25mm autocannon. This is the major weapon carried by the Wozangs, and is intended mainly for anti-aircraft protection, or for destroying any ancient moored mines. But minehunters can also be called out for patrol duty, and then the 25mm cannon would be used to deal with smugglers.
There are only six Wozangs, and the first of them entered service in 2005. These are the most capable mine hunters in Chinese service, using special sonar to detect bottom mines, and then sending a remote control mini-sub to confirm the type of mine, and plant an explosive to destroy it. The Wozangs carry a crew of about 30 and can stay at sea for about two weeks at a time.
But most Chinese minehunters are Type 6610s. These are based on a German World War II design (adapted by the Russians after the war as the Type 43, and passed on to China.) Only about a dozen of these are still in service, The Type 6610s are good ocean-going patrol boats, as are the Wozangs. But the Wozangs carry a lot of expensive mine hunting gear, and don't go on patrol much.