China claims to have successfully tested a new sea plane, purportedly the largest in the world, and while its primary purposes are firefighting and water rescue, this new aircraft could be used to advance the country’s ambitions in the disputed South China Sea.

The AG600 Kunlong, a domestically-built Chinese aircraft roughly the size of a Boeing 737, recently completed several on-water tests on a lake in central China, the Hong Kong-based South China Morning Post, citing China Aviation News, reported Sunday. It can reportedly even land in choppy seas with its hull-like fuselage.

During the testing in Hubei province, the aircraft was put through a series of water manoeuvring and low-speed flight tests, according to the Associated Press.

The aircraft made its maiden flight in December last year. Military experts reportedly believe that the latest tests indicate the plane could soon be ready for service.

The AG600 Kunlong, powered by four turboprop engines, has a significant carrying capacity. In a rescue situation, it could carry up to 50 people, and were it to be deployed for firefighting purposes, it could carry around a dozen metric tons of water.

Experts suggest that it could be used to move troops and equipment into the disputed South China Sea, where China has built militarised outposts armed with various point defence systems, jamming technology, anti-ship cruise missiles, and surface-to-air missiles. China even landed a heavy bomber at an outpost earlier this year.

“The AG600 would be suitable for the quick transport of troops and materials, and could also provide other support such as evacuating garrisons in the South China Sea or even out to the Spratlys,” Collin Coh, a research fellow in Singapore’s Nanyang Technological University’s Maritime Security Program, told SCMP.

“Beijing will also use it to justify any further build-up in the region, saying the aircraft can be used for the common good, such as providing support to foreign vessels in the area and for search and rescue,” he added.

A Beijing-based military expert suggested that the the AG600 Kunlong, the work of China Aviation Industry General Aircraft Co., can link countless islands in the South China Sea and play a big role in law enforcement, emergency rescue and even reconnaissance.” Ching Chang, a research fellow at Taiwan’s ROC Society for Strategic Studies, argued three years ago that the aircraft could play a role in “all the government functions that may signify its substantial governance in the South China Sea,” thus bolstering its previously discredited claims to the highly-contested region.

The South China Sea, which briefly took a back seat to the nuclear war crisis on the Korean Peninsula, has once again emerged as a hot-button issue. Not only has the Chinese military been threatening foreign ships and planes that venture too close to Chinese-occupied territories, but the Chinese military recently got into a standoff with a British amphibious assault ship that approached its South China Sea holdings.

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