The hardest working ships in the South China Sea are two Chinese two replenishment (“sustainment”) ships designed expressly tp support Chinese islands created or occupied in the South China Sea. Despite being less than ten years old, the two ships are scheduled for upgrades and eventually some major maintenance. The first of these ships entered service in 2015 and second in 2019. Named Sansha 1 and Sansha 2, they are kept busy supplying Sansha City island and many smaller islands to the south. The two Sansha ships are actually a smaller (7,800 ton) replenishment ship designed specifically for moving up to 2,200 tons of supplies and equipment per voyage to a lot of small island bases in the South China sea. They are RO/RO (Roll On/Roll Off) type ships so it is easier to drive vehicles off onto the docks being built on many of these tiny (some man-made) islands. The Sanshas have a helicopter pad for small (four ton) helicopters like the Z-9. They will replace most of the collection of commercial ships currently used to resupply these island bases.
One of the first upgrades for Chinese support ships is a DLS-16T Long-Distance Optoelectronic Monitoring System for each ship. These systems are designed to supply 24/7 omnidirectional search, observation, surveillance, and video evidence collection against maritime and aerial targets no matter what the weather conditions. Items recorded includes ships of all sizes, overboard people, objects floating in the sea, and aircraft. Similar systems are being installed on Woody Island and a dozen or more of the smaller occupied islands. All these surveillance systems send information back to a central system on the mainland where all the activity detected is merged to display a rather detailed picture of what manmade objects are in the South China Sea.
All Chinese activity and territorial claims got rolling in a big way after 2012, when China declared one of the Paracel islands (Woody Island) to be the center of a new Chinese municipality (city). Sansha is now one of 19 prefectures of Hainan province in southern China. Hainan is itself a large island off the Chinese coast with a population of ten million. Sansha City is the smallest prefecture in Hainan in terms of land area (13 square kilometers) and population (a few thousand). Sansha is actually Woody Island and dozens of smaller bits of land (some of them shoals that are under water all the time) in the Paracels and the Spratly Islands to the south. In fact, the new "city" lays claim to two million square kilometers of open sea (57 percent of the South China Sea). This is part of a strategy based on the ancient principle that, when it comes to real estate, "possession is 9/10ths of the law." It's the law of the jungle, because all the claimants are armed and making it clear that, at some point down the road, force will be used to enforce claims. Since 1975, there have been two naval battles, and dozens of minor clashes by the rival claimants to the Paracels. With the establishment of Sansha City, China is saying the next time it could be war, because a government has to defend its sovereign territory.
Currently Woody Island has a permanent population of nearly two thousand people who have to be supplied, even with water, at great expense from the Chinese mainland. Most island occupants are military and police personnel, who serve on the island for two years, and civilian officials, who serve six-month tours. There is a small fishing community and facilities for fishing boats to tie up and the crews to come ashore for some rest. There are also some tourist attractions. Woody Island is about 340 kilometers from Chinese territory (Hainan Island) and thus within China's exclusive economic zone (EEZ). The expense of maintaining Sansha is a minor cost when you consider that this move makes many disputed islands, atolls, and reefs officially part of China, at least as far as China is concerned.
At the time the first 7,800-ton Sansha ship entered service, China had already built eight of its larger (23,000 ton) Type 903A replenishment ships. Since 2013 there has been a massive acceleration in the production of these ships. The first two of these Type 903 tanker/cargo ships appeared in 2004. By 2008 these ships were regularly at sea supporting the task forces (each with at least two warships, plus the Type 903) sent to the anti-piracy patrol off Somalia for six-month tours. The replenishment ship did just that, supplying fuel, water, food, and other supplies as needed. The replenishment ship would go to local ports to restock its depleted stores and return to the task force. China needs more Type 903s to support its growing number of long-distance training operations into the Western Pacific, and the government has apparently ordered a lot more. One reason Chinese warships are now being seen all over the world (on official visits and to show off) is because there are enough replenishment ships to support this sort of thing.
The third and subsequent Type 903s built were called Type 903A because they were 12 percent larger than the first two (which displaced 20,500 tons each) but otherwise identical. The Type 903s are similar to the twelve American T-AKE replenishment ships. These 40,000-ton ships service a much larger fleet than the eight (so far) Type 903s and are part of a larger replenishment fleet required by American warships operating worldwide.
Meanwhile China has, since the 1990s, trained more and more of its sailors to resupply ships at sea. It’s now common to see a Chinese supply ship in the Western Pacific refueling two warships at once. This is a tricky maneuver and the Chinese did not learn to do it overnight. They have been doing this more and more over the last decade, first refueling one ship at a time with the receiving ship behind the supply ship and then the trickier side-by-side method. This enables skilled supply ship crews to refuel two ships at once.
China got a sharp reminder of how essential the replenishment ships are in April 2014 when they joined the international military effort to find missing flight MH370. China discovered it did not have enough Type 903s and, without access to foreign ports for resupply, the Chinese Navy could not sustain large numbers of ships far from China. Chinese naval planners have long warned of this and the political leaders are now paying more attention. China sent two dozen warships and support vessels into the southern Indian Ocean in April 2014, and it was obvious that without access to nearby Australian ports the Chinese ships would not have been able to remain in the area for long.
The classic solution to this problem is a large fleet of support ships to constantly deliver food, fuel and other supplies to ships at sea. China is rapidly building such ships, but not enough of them to maintain a large force for an extended period. China is unlikely to obtain the overseas ports it needs to support its current expansion plans because Chinese expansion plans have angered nearly all the nations in area. China does have a few allies, like Pakistan, Cambodia and Burma. This would not be enough if it came to outright hostilities and some of these friendly ports blocked by neighboring countries that are at odds with China.
This logistical weakness is no secret but the Chinese have long played it down. After the April 2014 MH370 operation it became a much more visible issue. Chinese naval threats are now a bit less intimidating, until there are reports that China is building more sustainment ships than it already is. That is apparently happening.
This is all part of a Chinese navy effort to enable its most modern ships to carry out long duration operations. In addition to the ships sent to Somalia, the Chinese have been sending flotillas (containing landing ships, destroyers, and frigates) on 10-20- day cruises into the East China Sea and beyond. The MH370 search off west Australia was the largest Chinese fleet deployment in modern times.
The Chinese have been working hard on how to use their new classes of supply ships. These are built to efficiently supply ships at sea. In addition to learning how to transfer these supplies at sea, the crews have also learned how to keep all the needed supplies in good shape and stocked in the required quantities. This requires the procurement officers learning how to arrange resupply at local ports in a timely basis. This was particularly important off Somalia, where warships often had to speed up (burning a lot of fuel in the process) or use their helicopters to deal with the pirates.
Modern at-sea replenishment methods were developed out of necessity by the United States during World War II because of a lack of sufficient forward bases in the vast Pacific. The resulting service squadrons (Servrons) became a permanent fixture in the U.S. Navy after the war. Ships frequently stay at sea for up to six months at a time, being resupplied at sea by a Servron. New technologies were developed to support the effective use of the seagoing supply service. Few other navies have been able to match this capability, mainly because of the expense of the Servron ships and the training required to do at sea replenishment. China is buying into this capability, which makes their fleet more effective because warships can remain at sea for longer periods.
China is one of the major producers of commercial ships and was able to begin construction of the first Sansha in 2012 and launch it in 2014. The design is unique and, to speed up the construction process, China bought the rights to an existing European design that had not been built yet.