China Shuts 73,000 sq km of Shanghai Airspace for 40 Days, Gives No Reason

China has banned civil aviation from a 73,000-square-kilometre zone off Shanghai for 40 days, with no official explanation for a restriction that is geographically unprecedented in its scale, duration, and opacity. The Notice to Air Missions (NOTAM) was posted online on March 27 at 11:50 GMT and took effect a few hours later, remaining in force until May 6, 2026.

It covers an area twice the size of Taiwan's main island, a few hundred kilometres north of the island itself. As reported by AFP and published by Gulf Times, the closure covers five separate zones spanning the Yellow Sea and East China Sea. These corridors lie between China and South Korea to the north and between China and Japan to the east, with no altitude ceiling, meaning the restriction applies to all aerial activity, including spacecraft trajectories.

What the NOTAM Covers and What It Does Not

The five restricted zones stretch approximately 340 miles from the Yellow Sea southward to the East China Sea near Shanghai. However, crucially, these are offshore military zones, not the flight corridors used by commercial airlines flying into or out of China's major airports.

International flights to Shanghai Pudong, Beijing Capital, Guangzhou Baiyun, and Chengdu Tianfu are not restricted, and they still run. The closed space is divided by an air corridor about 100 kilometres, but it allows access from Shanghai to the Yellow Sea by commercial traffic. Long-haul flights by Inkl Airlines over the East China Sea are being re-planned to avoid the areas with slight fuel consumption and route deviation, but no major overhaul of schedules.

The Reason Experts are Alarmed

What is unusual about this NOTAM is not its size but its duration, and overall lack of any altitude restrictions; a profile that has no civilian or routine explanation. Maritime security analyst Benjamin Blandin of the Institute of National Defense and Security Research in Taiwan said:

Gulf Times Aviation advisor Xavier Tytelman observed that

The Bigger Signal: Aviation as Geopolitical Indicator

Such airspace closures have become a dependable leading indicator of military intent, including the closure of airspace to Indian carriers in response to the Pahalgam attack, Iran-related disruptions causing Gulf carrier rerouting, and the recent unexplained 40-day reservation by China. Retired US Navy captain Jim Fanell evaluated the closure areas as possibly connected with a large-scale exercise like the previous exercises of Justice Missions. Moreover, the senior security officials of Taiwan have reported that China is taking advantage of the American focus on the Middle East to increase its Indo-Pacific military positioning. As the closure will be complete on May 6, just days before President Trump is scheduled to visit China May 14-15, the timing is, again, unto itself another layer of the picture that remains incompletely clear.