The pilot flying the Asiana Airlines jet that crashed in San Francisco, killing three people, was worried about landing successfully because a system used to guide planes down to the runway had been turned off during a construction project.
Testimony at a National Transportation Safety Board hearing on Wednesday offered many new details about Mr Lee Kang Kuk, an experienced 46-year-old pilot who was being trained on the 777 when the tail of the plane slammed into a seawall at the edge of San Francisco Bay.
Before the flight, Mr Lee was asked about his knowledge of the 777's autoflight system. He said he wasn't so confident and believed he needed to study it more.
The pilot said that he was concerned about arriving without help from an instrument-landing system. Controlling the descent, he said, "is very stressful."
Mr Lee said he had flown into San Francisco many times as a co-pilot on Boeing 747s but landed only a couple of cargo flights because Asiana captains were reluctant to turn over the controls to a first officer at "a special airport."
As the plane drew close to the runway, Mr Lee told investigators, he was momentarily blinded by a light "like a beam ... right in front of me." He couldn't say what color the light was or whether it was above or below the horizon. The instructor pilot sitting next to him did not notice it.
If an approach goes awry, pilots sometimes abort a landing, pull up and circle again before coming back to the runway. Mr Lee told NTSB investigators that he didn't do a "go-around" because he believed that only the instructor pilot who was in the cockpit had the authority to make that emergency decision. Instructor pilot Lee Jung Min said he began a go-around just before the tail slammed into the seawall.
The instructor told investigators that he didn't notice anything wrong with Mr Lee's ability during the takeoff in Seoul and the high-altitude cruise across the Pacific. When the approach to San Francisco started, the pilot's response seemed late for the conditions, but the instructor thought that Mr Lee "was okay and aware" of the landing procedure, investigators reported.