After two hours of nothing but the vast expanse of the East China Sea, a steel structure topped by a streak of flame and a helicopter pad appears on the horizon, growing rapidly in the window of a Maritime Self-Defense Force P-3C patrol plane.
The Chinese have built this production platform atop the Pinghu oil and natural gas field, which lies half-way between Japan and China, about 430 km northwest of Naha, Okinawa Prefecture.
In recent years, China has been increasingly active in marine research in the area, including waters that Japan claims are within its exclusive economic zone.