 However, since the Chinese economic reform and the depletion of the fishery resources, the civilian fishing vessels must venture much further out into open ocean and staying longer at the sea, thus could no longer afford to stay in home waters and performing the heavy inshore surveying duties previously assigned under the planned economy era in China prior to the Chinese economic reform.Consequently, the PLAN must come up with their own means to meet such huge demand, and converting former gunboats was one of the answers