Pilots of fatal Asiana Airlines crash knew speed was low

WASHINGTON - Pilots of an Asiana Airlines plane that crash-landed in San Francisco in July were aware that the plane was traveling too slowly and tried to correct it in the final seconds before impact, documents released on Wednesday by US aviation safety investigators show.

The crash on July 6 killed three people and injured more than 180, the first fatal commercial airplane crash in the US since February 2009. The co-pilot of the jet, who was training the pilot flying the plane, thought the autothrottle on the Boeing Co 777 plane might not have been operating, the documents show.

The pilot who was flying the plane said he wasn't sure whether autothrottle was maintaining speed, documents show.

The low, slow landing caused the plane's tail to hit a seawall short of the runway. The plane spun 330 degrees as it broke apart and caught fire, strewing wreckage along the runway.

The National Transportation Safety Board released dozens of detailed documents related to the crash as it opened an investigative hearing into its causes.