The Asiana Flight 214 crash last year at San Francisco International Airport killed three people and injured more than 180. Since that time, federal officials have been investigating how and why the crash occurred. Today, they came to the conclusion that "mismanagement" by the pilots caused the plane to hit the edge of the runway and spiral out of control. 

The National Transportation Safety Board looked at the skill and experience of the pilots involved, the computerized flight systems, and the throttle system on board, which is meant to adjust automatically the plane's speed. Investigators say the pilots accidentally turned that system off during approach.

The authorities determined that of all these factors, the pilots seemed to be the issue. There was confusion in the cockpit about the key controls of the Boeing 777. The controls are complex, and it seems the pilots lacked the training needed to manage them. They often relied on automated controls without fully understanding how they worked. Because of this, the pilots landed at too slow a speed, and too low to the ground to be able to touch down as intended, instead hitting a sea wall. 

During the investigation, federal authorities interviewed other Asiana pilots, reviewed Asiana policies, and studied training procedures. They also looked into the contents of the black box. Since the crash, Asiana has overhauled their safety policies and training program. They focused on adding more flight simulation training for landings, specifically.