The pilots of an Asiana Airlines Inc. plane that crashed in San Francisco, new to their roles and to working together, struggled to line up the jet for landing while realizing it was going too slowly, they told investigators.
The pilots thought they had set the correct speed in the Boeing Co. 777 and didn’t realize they were going too slowly until seconds before impact, U.S. National Transportation Safety Board Chairman Debbie Hersman said today in the first description of interviews with the crew.
The instructor monitoring the pilot at the controls realized the plane wasn’t making a proper approach at an altitude of about 500 feet, Hersman said.
“He told the pilot to pull back,” Hersman said.
In addition to the flight marking the first time the pilot at the controls had tried to land a 777 in San Francisco, it was the first time the instructor had flown in that role and the first time the two had flown together, she said.
Hersman’s briefing provided the most detail so far of the final minutes of Flight 214, showing the pilots realized they were in coming in too low and slow before someone in the cockpit ordered evasive action seven seconds before impact. By that point, the plane was moving so slowly it was on the verge of losing lift.
All but two of the 307 people on board survived, with at least 23 still hospitalized. It was the first fatal crash in the U.S. of a large jet since 2001, and Seoul-based Asiana’s first such accident since a Boeing 747 cargo plane went down at sea in July 2011.
Hersman described other details of the flight’s final moments and impact for the first time, confirming some passenger accounts that at least one emergency chute went off inside the plane after impact, trapping a flight attendant.
Two other flight attendants were ejected from the rear of the plane on impact and landed near the runway, she said. Both survived with unspecified injuries.
Lee Kang Kuk, a veteran pilot with 43 hours’ experience in the 777, was at the controls of Flight 214 on approach under the supervision of a senior management pilot, according to the airline.
Lee had flown 10 legs on the 777 and was about halfway through his training period on the new aircraft type, Hersman said. The 46-year-old has flown 9,793 hours, according to South Korea’s Transport Ministry. The pilot had flown to San Francisco 29 times as a co-pilot on Boeing 747s and other aircraft, Asiana Chief Executive Officer Yoon Young Doo said today.
Lee Jung Min, 49, who has 3,220 hours’ experience on Boeing’s biggest twin-engine plane, was in command. He received his trainer license for the 777 last month and, according to Hersman, was making his first flight as an instructor.
It’s not unusual for a pilot to conduct training after holding a trainer license for almost a month, Chang Man Heui, an aviation policy official at South Korea’s transport ministry.
“It’s ridiculous to doubt his experience based on how long he’s held a trainer license,” Chang said. Earning the license is “recognition of experience,” he said.
Investigators are trying to determine how the pilots set the auto-throttle and whether it was worked properly. The device flies the plane at a speed selected by pilots and has built-in functions to keep the plane from slowing too much.
The plane had slowed to almost 40 miles (64 kilometers) per hour below its target speed before hitting the seawall short of the runway, Hersman said yesterday.
The auto-throttle was “armed,” meaning it was capable of being engaged, Hersman said today. Investigators are attempting to determine how it was being used and how the pilots programmed it, she said.
Cockpit automation has played a role in several recent accidents by confusing pilots, particularly when they became startled or the equipment acted in unusual ways, Rory Kay, the former air safety chairman of the Air Line Pilots Association, said in an interview. ALPA is the largest pilots’ union in North America.
“How well trained are we to handle departure from the norm?” said Kay, who declined to discuss the Asiana accident.
The automation in the 777 and similar models from Airbus SAS is so good that pilots have come to depend on it, said David Woods, an Ohio State University engineering professor who has studied the issue.
“It is making things go smoothly and effectively. When it doesn’t, it’s kind of a surprise,” he said.
The pilots had difficulty lining up the plane for the proper landing position without a so-called glide-slope indicator, a radio beam that gives pilots a steady descent path. The indicator on the runway being used by the Asiana flight hadn’t been working since June due to construction, which the U.S. Federal Aviation Administration had told pilots in a bulletin.
According to previous NTSB briefings, the pilot flying the plane turned off the autopilot at 1,600 feet of altitude 82 seconds before the crash. At 1,400 feet a few seconds later, the plane was flying at 196 mph.
The speed fell as the aircraft neared the runway, dropping below the target landing speed of 158 mph. It got as low as 119 mph three seconds before impact.
The jet slowed so much that a cockpit warning of an impending aerodynamic stall sounded four seconds before it crash-landed.