The US Navy P-8A Poseidon jet was flying at 16,500 feet to get a view of low-lying coral reefs that have been turned into garrisons with five-storey buildings, large radar installations, power plants and runways sturdy enough to carry large military aircraft.
During the flight that was giving journalists from CNN a rare look at the islands, the crew was warned six times by the Chinese military to get out of their territory.
A voice said: “US military aircraft, this is China … leave immediately and keep out to avoid any misunderstanding.”
Each time the aircraft was challenged by the Chinese military, the US Navy crew’s response was the same.
The response was: “I am a sovereign immune United States naval aircraft conducting lawful military activities beyond the national airspace of any coastal state.
“In exercising these rights as guaranteed by international law, I am operating with due regard for the rights and duties of all states.”
CNN was granted the chance to see how the Chinese government is rapidly expanding its militarisation efforts from a US reconnaissance plane when the harsh threat was issued.
The US Navy jet had flown over four key artificial islands in the Spratly chain where China has built up fortifications: Subi Reef, Fiery Cross Reef, Johnson Reef and Mischief Reef.
Before the crew were warned, the jet’s sensors picked on 86 vessels on the Subi Reef that included Chinese coast guard ships. On the Fiery Cross Reefs, rows of hangars stood alongside a lengthy runway.
LT. Lauren Callen who lead the air combat crew on the Navy flight said: “It was surprising to see airports in the middle of the ocean.”
Subi Reef in 2016. Now there’s a runway and hangars.