Chinese aviation authorities are investigating how the cockpit windshield of a Sichuan Airlines Airbus A319 jetliner blew out in midair, endangering the plane and those on board.

The plane was flying at 32,000 feet to the Tibetan capital Lhasa from the western city of Chongqing on Monday when its front right windshield became detached, exposing the cockpit to the freezing, low-pressure atmosphere outside.

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