By JANE PERLEZ SEPT. 15, 2015 From NY Times: 

BEIJING — New satellite images show that China has started construction of an airstrip on a third artificial island in the South China Sea that will strengthen Beijing’s military capacity in the contested waters, Western analysts say.

The photographs, released by the Center for Strategic and International Studies in Washington, show preparation for airfields on Mischief Reef and Subi Reef, submerged reefs in the contested Spratly Islands that China has transformed into islands, according to the center.

The airstrip on Mischief Reef is about 20 miles from a small Philippine military garrison on an existing tiny island and will put the installation under great pressure, said James Hardy, Asia-Pacific editor of IHS Jane’s Defense Weekly.

That airstrip will most likely be used for turboprop patrol, but it could easily be equipped for “full military action” if needed, Mr. Hardy said. The most important function of the strip, he said, will be as yet another site for Chinese listening devices and early warning radar, much like the technology being installed on Woody Island in the Paracel Islands of the South China Sea, which are also contested. Evidence of that will probably appear soon on Mischief Reef, he said.

China completed a 10,000-foot runway several months ago on Fiery Cross Island, one of five artificial islands it has created in a large reclamation project in the South China Sea this year.

The South China Sea is one of the top areas of disagreement between China and the United States that will be discussed during a state visit by President Xi Jinping to Washington next week.

The Obama administration has called on China to stop land reclamation, construction and militarization of South China Sea outposts, a policy that Washington calls the “three noes.”

Washington has expressed concern that the military capacity on the reclaimed islands will interfere with freedom of navigation in the area, one of the world’s busiest waterways. With these military runways, the zone of competition between the United States and China across the South China Sea has expanded significantly, experts say.

But China has rebuffed Washington, repeatedly saying that it has “indisputable sovereignty” over about 80 percent of the South China Sea and the right to build what it wants on the Spratly and Paracel archipelagoes.

In June, China’s Foreign Ministry said Beijing would stop reclamation on the five artificial islands but would continue to build facilities on them. At the time of the statement, Beijing appeared to have finished much of the reclamation carried out by large flotillas of dredges.

After a speech to Chinese and Western journalists in Beijing on Tuesday,Yang Xiyu, a senior fellow at the China Institute of International Studies, said “difficulties between the United States and China on the South China Sea will continue for a long time.”

There is little chance, he said, that the sharp differences will be resolved at the meeting between Mr. Xi and President Obama. The best that can be expected is a “consensus” to manage the differences, he said.

In April, when satellite images showed that China was building the 10,000-foot runway on Fiery Cross, 170 miles west of Mischief Reef, American military analysts called the installation a strategic game changer. The size of the runway meant a fighter jet could land on the island, they said.