MELBOURNE, Australia — It appears China has put at least one other semi-submersible transport ship into service with the People’s Liberation Army Navy, according to photos published by state media showing the ship transporting an amphibious hovercraft.

The official China Military Online website showed the semi-submersible heavy ship Yinmahu transporting a Type 958 air-cushioned landing craft.

The Yinmahu is similar in layout to the semi-submersible expeditionary transfer dock of the U.S. Navy’s Military Sealift Command. It is also externally similar to the Donghaidao, the first-of-class ship commissioned into China’s PLAN in July 2015.

According to China Military Online, the Yinmahu transported the Type 958 while the former was “attached to a landing ship group with the navy under the PLA Southern Theater Command.” This suggests the Yinmahu was assigned to that command like most of the PLAN’s modern amphibious fleet units.

The PLAN’s designation of the ship type is unknown, but the U.S. Navy’s Office of Naval Intelligence calls it the “Modified Hansa Sonderberg class” because its design originates from the civilian ship class of a similar name. The intel office’s most recent public report on China’s maritime forces did not mention a second ship in the class.

According to figures published at the commissioning of the Donghaidao, that ship measures 175.5 meters (575.8 feet) long with a beam of 32.4 meters and has a displacement of roughly 20,000 tons.

This is substantially smaller than its counterpart in the U.S. Navy — the Montford Point-class expeditionary transfer dock, which is 785 feet long with a beam of 164 feet and a displacement of 78,000 tons.

Both designs are meant for air-cushioned landing craft or possibly other amphibious vehicles to launch or dock off its sides in order to conduct amphibious and landing operations when port facilities are unavailable.

The Type 958 is the Ukrainian designation of the Russian Zubr class, otherwise known as Project 1232.2. China had bought two such vessels from Ukraine with plans to build more locally, only to switch the contract to Russia in 2014 when Moscow annexed Crimea, where they were undergoing construction.

China subsequently built at least four more of the landing craft, which measure 57 meters in length with a beam of 25.6 meters and a displacement of 555 tons when full loaded to its capacity of three main battle tanks or 500 troops.

In addition, China has a similar civilian-owned, semi-submersible heavy transport ship with a 50,000-ton displacement. It’s likely that ship would come under the PLAN’s command during a contingency.

Mike Yeo is the Asia correspondent for Defense News.

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