Chinese Shipyard Looks to Build Giant Floating Islands

China, not just satisfied with turning South China Sea reefs into airports, is looking to expand its naval basing activities by building giant floating islands.

The Jidong Development Group (JDG), a construction company, and Hainan Hai Industrial Company (Hai is Mandarin for ocean) are proposing to build a floating sea base for multipurpose usage, such as tourism, shipping, power generation and offshore fossil fuel extraction. The floating sea base would be based in the South China Sea, for logistical support activities.

Currently, the largest offshore floating platforms are natural gas and oil production facilities, of which Australia Shell's Prelude is the world's largest. Built by Samsung Heavy Industries and Technip, the Prelude is 488 meters long, 74 meters wide and has a full displacement of 600,000 tons. The Prelude has a catamaran ship's double hull and is currently anchored off northwest Australia's eponymous gas field.

JDG's floating island designs are modular, being assembled from multiple semi-submersible hull sections. They would come in three sizes. The smaller island is 300 meters long and 90 meters wide, the medium sized island is 120 meters wide and 600 meters lond, while the larger island is 900 meters long and 120 meters wide. Assuming a hull draft of around 16 meters, full displacement of the islands could likely be around 400,000 and 1.5 million tons, respectively.

The design though would allow the islands to scale much larger, by attaching more semi-submersible hull modules, just like Lego bricks. Despite the large size of the individual modules, the floating islands could be easily assembled in deep offshore waters by linking together modules transported by semi-submersible heavy lift ships from landbased shipyards.

The technical description of the JDG floating island is a "deep sea support base." That is, unlike an actual island, they will be mobile. JDG General Manager Wang Yandong said that the islands can move at speeds of up to 18 kilometers an hour. The floating islands could serve as an offshore wind farm, oil production and as a rapidly deployable offshore port. While JDG has mentioned the island's potential as sea mobile resorts to move between northern Bohai Bay in the summer and tropical Hainan during winter, the presence of a PLA officer at the JDG press conference raises interesting questions about future military interests in the JDG's floating islands.

Floating island plans in war have ranged from the Royal Navy's Project Habbukak, a massive ice and concrete aircraft carrier built in prototype in World War II, to US Navy's Joint Mobile Offshore Base plan in the early 2000s, of which studies called for being able to accommodate a 1.5 mile long airstrip. The goal of such programs is that a mobile floating island could carry many times more aircraft and soldiers than a carrier or amphibious assault group. An additional military advantage to China's modular floating island design is that its large size and compartmentalized construction would make it very difficult to sink (an opponent would have to strike a large number of the modules to compromise the island's seaworthiness).

For China, a floating island airbase, besides obvious deployments to disputed islands, could be a new kind of tool for global military projection, notably addressing one of China's strategic weaknesses compared to the US, its dearth of foreign military bases. In the near future, China could stage anti-piracy missions and humanitarian relief from well stocked floating islands. More forceful uses of floating islands could be temporary or permanent deployments off the waters of potential battlefields.

Thanks to: Hongjian, Jeff Head and Henri K.