Satellite photos show Chinese nuclear sub entering mysterious undersea cave base

Military observers across social media are abuzz after a satellite photo emerged that appears to show a Chinese submarine entering an underground base on the southernmost island of Hainan on the South China Sea.

The rare satellite image, which was captured Aug. 19 by Planet Labs and released on social media by the U.S. government-funded Radio Free Asia, shows a Type 093 nuclear-powered attack submarine belonging to the the Chinese People’s Liberation Army Navy (PLAN) Submarine Force entering a subterranean tunnel to an underground berth at the important Yulin Naval Base.

The image is also causing interest because other submarines aren’t visible in the image of the strategic base. The other docks in the image are completely empty, raising questions among online users as to where China’s nuclear-powered vessels might be.

Yulin Naval Base, Hainan, #China is home to a large underground facility with covered tram from magazine to loading areas pic.twitter.com/cIv9MPC0cy

— Sentinel (@StratSentinel) February 18, 2017

The images quickly drew comparisons to spy films such as James Bond, as well as a reference to the fictional Nautilus, from Jules Verne’s novel “20,000 Leagues Under the Sea.”

The Yulin Naval Base on Hainan Island is a strategic location for myriad reasons. The base lies nearly 300 miles southwest of Hong Kong and is home to China’s nuclear ballistic missile submarine fleet, which is crucial to China’s second-strike abilities. The base also lies on the northern edge of the disputed South China Sea, which has been the source of friction with neighboring Brunei, Indonesia, Malaysia, the Philippines, Taiwan, Vietnam, and a U.S. keen on maintaining its hegemony in the Asia-Pacific region.

As China has grown richer and more powerful militarily, the country has also grown more assertive in establishing and defending its sovereignty in the strategic South China Sea, drawing contentious reactions from the East Asian giant’s regional and geopolitical rivals.

And with Washington and Beijing remain embroiled in bitter trade talks and growing tensions, the U.S. Navy – as well as private imaging companies – are turning more attention to the disputed waters, as was the case when a P-8 maritime patrol aircraft flew over the South China Sea last week.

Submarine was exiting stern first, and was pushed towards the piers outside the bunker. All of China's other submarines normally stationed here are nowhere to be seen – wonder where they went… pic.twitter.com/ZFERRGeHQI

— Drake Long (@DRM_Long) August 20, 2020

The Chinese People’s Liberation Army is known to hide many of its strategic assets underground, which comes naturally for a military with historical roots as a guerilla force that often relied on subterfuge and tunnel warfare tactics during the 1937-1945 war against Japanese occupation and the country’s communist revolution. The country’s long martial history is also rich with stories of underground military facilities.

China is also known to have a so-called “Underground Great Wall” in the form of a labyrinthine tunnel network meant to conceal, mobilize and deploy intercontinental ballistic missiles.

Any move by China to conceal its submarine fleet from rivals’ surveillance systems by hiding them in underground tunnels robs potential adversaries from accurately assessing the country’s military strength and also from ensuring that the strategic vessels, as well as Chinese military preparations, remain elusive.

“You have no evidence of (the submarine’s) combat readiness, operational response times and availability,” said Carl Schuster, a former director of operations at U.S. Pacific Command’s Joint Intelligence Center, to CNN. “Tunnels blind potential opponents to the submarines’ operating status and patterns, denying them the ability to determine the state of China’s military preparations, knowledge critical to assessing China’s intentions and plans.”