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What was the US P-8 spy plane doing off China’s Hainan Island?

By Timothy Liu on August 29, 2014 • ( 1 )

A comparison of satellite images of Yulin Naval Base from 2004 (left) and 2013 (right)

By now, half the world is aware of the reckless manner in which an armed PLA Navy fighter jet performed a ‘dangerous intercept’ of a USN P-8 Poseidon Maritime Patrol Aircraft (MPA) while it was performing what apparently was routine surveillance on… something. The media has been terming the P-8 as a spy plane and indeed it was as it was performing reconnaissance in the vicinity of Hainan Island, also the site of the 2001 EP-3 collision incident.

While the public diplomatic firestorm has been over the conduct of the Chinese pilot, more subtle questions have been left mostly unanswered. What was the P-8 doing off Hainan Island, and does it warrant the Chinese pilot’s dangerous actions? I personally find it hard to believe that any pilot would willingly perform such a dangerous intercept had there not been something greater at stake.

Yulin (Sanya) Naval Base

2013 satellite image of Yulin Naval Base. The underground facility and demagnetisation facility has been marked.

Hainan Island appears to house China’s newest (known) naval facility, the Yulin Naval Base. It also appears to house an underground facility to hide submarines from spy satellites, allowing China, to some extent, to be able to disguise or mask the extent of its submarine force and to inhibit determination of how many subs are not berthed and thus are at sea.

This is of strategic importance because the whole reason for submarines’ operational effectiveness is stealth: the less “they” know, the better off you are. The more China can hide about her submarine fleet to the outside world, the more effective the fleet is as a deterrent to any potential aggressors.

2004 Image: The majority of the base infrastructure, along with breakwaters, are almost completed. Piers have not been constructed.

2013 Image: Land facilities have visibly become more developed. Piers have been constructed: two 950m piers capable of accommodating aircraft carriers and 4 smaller 250m piers. What appears to be a demagnetisation facility has also been constructed, and the presence of an underground facility becomes clear.

Entrances and inroads cut into the hill. Also under construction appears to be a path to the top of the hill which leads to a clearing (far right of the image), which could be a base for a radar station.

The demagnetisation facility, also known as a degaussing facility, is a first for the PLA Navy. Its purpose is to remove any magnetisation or electrical charges from the hull of a submarine in order to make it more stealthy. It also prevents the submarine from triggering magnetic mines.

An unsubstantiated claim on Wikipedia states that the underground facility, consisting of caverns under the hills marked, is estimated to be capable of hiding up to 20 nuclear submarines from spy satellites. The source of that claim appears to be a 2008 Telegraph article, which also claims that the US Department of Defense has estimated that China will have five Type 094 nuclear submarines operational by 2010 with each capable of carrying 12 JL-2 intercontinental ballistic missiles, likely to be based at Yulin. Still, the picture is clear: this naval base is huge and of strategic importance. More images below.

Now we know the probable target of the P-8 surveillance. Next question, just what was it doing?

It is postulated that the P-8 actually dropped some kind of sonar buoy into the sea with the aim of keeping a watch on naval activity around the Hainan Island, thus threatening the submarine operations at the Yulin Naval Base. This most likely was the source of provocation that led to the aggressive intercept of the P-8 to deter further spying in every sense of the word. We can only be glad that unlike the 2001 incident, no one was hurt.

Sea-based entrance into underground facility

Chinese ships berthed at the 950m piers. Note the size of the piers relative to the ships.

Two 90-odd metre submarines and one approximately 130 metre submarine berthed at the smaller piers. The two submarines are possibly Type 091 SSNs and the larger one is most likely the Jin-class, Type 094 SSBN. The VLS on the 094 are visible.

This article first appeared on Temasek Thunderbolt, written by this author