Over the past 15 years, the Chinese navy's East Sea Fleet has been fortifying its military hardware in preparation for a fight against Taiwan. Along with the steady expansion of the fleet, huge investments have gone into modernizing and upgrading navy bases.

In particular, submarine bases and airport facilities have undergone major revamping. Satellite photos have confirmed that the Hainan Sanya Base of the No. 2 Submarine Flotilla of the navy's South Sea Fleet and the base of the No. 1 Submarine Flotilla of the North Sea Fleet all have gone underground.

Underground facilities are under construction for the East Sea Fleet as well, where additional 039A, Kilo 636 and Kilo 636-M diesel submarines are entering service.

Similar underground facilities also have been detected at Daxie Island in Zhejiang province, where 039A and 035G diesel submarines are based. At the Xiangshan Naval Base on the island, where Kilo 636 submarines are anchored, underground ammunition depots or fuel depots may have been constructed right in the middle of the hills.

Some Russian experts confirmed to the author that they helped China construct the first maintenance center for its Club-S submarine-launched missiles and repair facilities for Kilo diesel submarines in this area. The People's Liberation Army navy built its Kilo submarine base at Xiangshan because the island has a quiet harbor surrounded by mountains, making it easier for the submarine fleet to hide.

The Dinghai and Zhoushan naval bases, with four 956-E/EM DDGs and four 054/054-A FFGs entering service in the East Sea Fleet, also have undergone expansion. A new No. 3 Destroyer-Frigate Flotilla has been established, and two broad docks have been constructed specifically for the 956-E/EM DDGs.

The new flotilla also includes the newly commissioned No. 525 and No. 526 Type 054 class FFG and the last batch of Type 053-H3 class FFGs (No. 527 and No. 528).

This deployment is in line with the navy's principle of centralizing its crack forces and weapons. This new flotilla has become the most powerful frigate unit of the East Sea Fleet.

The Zhoushan and Dinghai bases are extremely large, with fuel depots, gigantic hoister cranes and dry berths already in place on site, indicating that basic repair services for surface warships and dock landing ships also can be done there.

At the Dinghai Base, five large dock bridges have been identified, which are used mainly to accommodate missile frigates and destroyers, each of which can anchor two to four surface warships. At this particular base, the port is at least 5 miles long.

The East Sea Fleet is armed mainly with 053-H3 FFGs and Luda class DDGs, and the expansion of its submarine fleet has been a top priority over the years. At Daxie Island, seven dock bridges are used to anchor the 039As and 035Gs. Each of them can accommodate two to four submarines.

Some of these submarines have been heard starting their diesel engines at around 7 a.m. to warm them up. When setting out on a voyage, if two submarines are anchored parallel at the dock, the one on the outer side will sail out first and return to position after the submarine on the inner side has left the dock.

(In Part 2: A shortage of submarine docks.)

(Andrei Chang is editor in chief of Kanwa Defense Review Monthly, registered in Toronto.)