Safety Board: Switch Mistake Nearly Flips ANA 737

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On Sept. 6, an ANA 737-700 with 117 aboard rolled through 130 degrees of bank and lost more than 6,000 feet of altitude partly due to poorly placed switches, according to Japan's Transport Safety Board's (JTSB's) preliminary report. No serious injuries were reported. Flight NH140 was cruising at 41,000 feet out of Okinawa for Tokyo when the captain left the cockpit. Upon his return, the co-pilot reached for what he thought was the control that unlocks the cockpit door and moved it to the left. The preliminary report states that the pilot instead grabbed and moved to the left the rudder trim control, which on the incident aircraft shares a similar position at the rear of the control pedestal. The four-year old jet then reacted to that control input as it should.

In response to the control input, the jet rolled left past 130 degrees and pitched 35 degrees nose-down. It lost 6,300 feet and pulled 2.68G during recovery. Be the time the aircraft had stabilized it was flying more than 200 degrees off course at an altitude of 34,700 feet. The aircraft had entered the maneuver while flying on autopilot, according to JTSB, but was upset by a left turn input recorded at the rudder trim control. Two flight attendants suffered minor injuries. ANA apologized Wednesday for the incident and said that it had not reported the incident until the following day. ANA said it will take measures to ensure that pilots double-check the location of the controls whenever anyone leaves or enters the cockpit. Additional measures may follow. The event may have overshadowed the Wednesday arrival of ANA's first Boeing 787 Dreamliner jet at Tokyo's Haneda Airport. The company is the launch customer for the aircraft.