The co-pilots of the All Nippon Airways did not come to know for about 17 seconds that the aircraft was almost turned upside down during a flight last year. The incident was reported by the Japan Transport Safety Board on August 31, 2012.

The incident happened on September 6, 2011, when an ANA flight was carrying 117 passengers and crew on board. The flight had dived 1,900 meters within 30 seconds off the southern Shizuoka district.

The incident happened when the co-pilot was trying to unlock the cockpit door for the captain who was returning from the toilet and mistook the command button for the cockpit door lock switch nearby. The reports also said that the co-pilot only noticed something went wrong 17 seconds after the rudder was operated.

The aircraft had took off from Naha in Okinawa in south. But fortunately the flight managed to land safely at Tokyo’s Haneda airport. Two of the crew members were slightly injured while four of the passengers reported health problems after the incident. Some of the images from the flight recorder on the Boeing 737-700 showed the plane veered to the right and then sharply to the left before it dropped backwards. The aircraft had also tipped almost more than 130 degrees to the left at one point.