An All Nippon Airways (ANA) Boeing 737 carrying 117 people nose-dived and went almost belly-up over the Pacific on September 6, 2011.
The co-pilot wanted to open the cockpit door for the captain returning from a restroom break. However, he mistook the rudder trim knob for the cockpit door lock.
The rudder knob and the door lock switch are no more than 3.9 inches (10 cm) apart. As the picture shows, unlocking the door (the small