The Wall Street Journal reports that a stewardess may have "mistakenly" pressed a switch in the pilot's seat while serving food. This triggered a function that gave the pilot back control of the aircraft, which immediately began to sink.
The incident occurred last Monday when the device, a Boeing 787 Dreamliner, rapidly lost altitude while flying over the Tasman Sea between Australia and New Zealand. Several passengers were ejected and hit the roofs, and a baby even flew a few meters.