The footage was released by the
Investigators warned the audience before airing the video at the hearing the footage was "potentially disturbing."
The new footage was taken from a fixed security camera and captures the moments before and after Asiana Flight 214 struck a seawall on approach. The jetliner then slammed into the runway, severing its tail section and scattering wreckage across the pavement. The July 6 crash killed three passengers and injured 180.
The initial investigation indicated the pilots failed to maintain the minimum speed and altitude required for a safe landing.
Lee Kang Kuk, 46, who was landing at the airport for the first time, told NTSB officials in an interview the visual approach was difficult to perform in the large
Though Lee said he thought the automatic throttles were working, investigators found the device had been shifted from "thrust" mode to "hold" mode during the approach and no longer controlled the airspeed.
As a result, the required landing velocity of 137 knots fell to 103 knots, 34 knots below the necessary landing speed.
According to the report, Kuk's ground school instructor had instructed his students that when the automatic throttle is put in hold mode, it would not automatically re-engage in a descent.
Before the crash, Lee said he was not that confident about operating the Boeing 777s automated flights systems and felt he needed more study, according to the report.
The investigation has focused on whether the automatic throttles were working properly and how closely the Asiana pilots were monitoring their altitude and speed during the landing.
During Wednesday's hearing, representatives of the Boeing Co. stressed that safety is ultimately the responsibility of the pilots, not automated flight systems.