SAN FRANCISCO The pilots involved in the Asiana Airlines flight 214 crash in San Francisco told federal investigators that they set the automatic throttle controls on the plane for a proper landing speed and then discovered to their surprise that at the last moment, the plane had slowed far beyond that setting.
In an afternoon press conference on Tuesday, National Transportation Safety Board Chairman Deborah Hersman spoke of the four pilots on board the plane and what they were doing leading up to the crash. Three of them were on the flight deck at the time of the landing.
Of the supervising pilot on the flight deck, Hersman said:"He reported that this was his first trip as an instructor pilot. This was the first time that he and the flying pilot that he was instructing had flown together."
As CBS News correspondent John Blackstone reported, teams of NTSB investigators are examining the plane inside and out, locating and recording every piece of debris from landing gear ripped from the jet to the smallest piece of fuselage.
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The cockpit could hold clues to verify statements given by the pilots. The pilot in control of the plane was sitting in the left-hand seat. it was his first landing at San Francisco in a Boeing 777.
He was being trained by the captain sitting in the right-hand seat. The senior pilot had 3,000 hours flying experience in a 777. But the airline says he was certified as a trainer just last month.
The supervising pilot typically is responsible for taking control of the plane if something should go wrong.
"At about 500 feet," said Hersman, "he realized that they were low. He told the pilot to pull back."
The flight data recorder indicates the plane was traveling 40 mph slower than it should have been for landing--so slow it triggered a warning system that shook the flight controls in the pilots' hands -- an alert the plane was losing lift and about to stall.
Just 1.5 seconds before the crash, the pilot attempted to abort the landing. The engine started speeding up, but it was too late to get them to full power.
In the interviews, the pilots said that they had set the auto throttle at 137 knots. That's the typical landing speed for the 777. What the NTSB has to confirm now is whether or not those controls were working.
Also, two flight attendants working in the back of the plane were ejected and survived, according to the NTSB.
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The plane's airspeed has emerged as a key question mark in the investigation. All aircraft have minimum safe flying speeds that must be maintained or pilots risk a stall, which robs a plane of the lift it needs to stay airborne. Below those speeds, planes become unmaneuverable.
Because pilots, not the control tower, are responsible for the approach and landing, former NTSB Chairman James Hall said, the cockpit communications will be key to figuring out what went wrong.
"Good communication with the flight crew as well as the flight attendants is something I'm sure they're going to look at closely with this event," he said Tuesday. "Who was making decisions?"
Hall was on the transportation board when a Korean Airlines Boeing 747 crashed in Guam in 1997, an accident investigators blamed in part on an authoritarian cockpit culture that made newer pilots reluctant to challenge captains.
Since then, the industry has adopted broad training and requirements for crew resource management, a communications system or philosophy airline pilots are taught in part so that pilots who not at the controls feel free to voice any safety concerns or correct any unsafe behavior, even if it means challenging a more senior pilot or saying something that might give offense.
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If any of the Asiana pilots "saw something out of parameters for a safe landing," they were obligated to speak up, said Cass Howell, an associate dean at the Embry-Riddle Aeronautical University in Daytona Beach, Fla.
"There are dozens and dozens of accidents that were preventable had someone been able to speak up when they should have, but they were reluctant to do so for any number of reasons, including looking stupid or offending the captain," said Howell, a former Marine Corps pilot.
There's been no indication, from verbal calls or mechanical issues, that an emergency was ever declared by pilots. Most airlines would require all four pilots to be present for the landing, the time when something is most likely to go wrong, experienced pilots said.
"If there are four pilots there, even if you are sitting on a jump seat, that's something you watch, the airspeed and the descent profile," said John Cox, a former US Airways pilot and former Air Line Pilots Association accident investigator.
Investigators want to nail down exactly what all four pilots were doing at all times.
"We're looking at what they were doing, and we want to understand why they were doing it,." Hersman said Monday. "We want to understand what they knew and what they understood."
It's unlikely there was a lot of chatter as the plane came in. The Federal Aviation Administration's "sterile cockpit" rules require pilots to refrain from any unnecessary conversation while the plane is below 10,000 feet so that their attention is focused on taking off or landing. What little conversation takes places is supposed to be necessary to safely completing the task at hand.
Choi Jeong-ho, a senior official for South Korea's Ministry of Land, Infrastructure and Transport, told reporters in a briefing Tuesday in South Korea that investigators from both countries questioned two of the four Asiana pilots, Lee Gang-guk and Lee Jeong-min, on Monday. They planned to question the other two pilots and air controllers Tuesday.
Choi said recorded conversation between the pilots and air controllers at the San Francisco airport would be investigated, too.
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Asiana Airlines crash in San Francisco
In addition, authorities were reviewing the initial rescue efforts after fire officials acknowledged that one of their trucks might have run over one of the two Chinese teenagers killed in the crash. The students, Wang Linjia and Ye Mengyuan, were part of a larger group headed for a Christian summer camp with dozens of classmates.
Asiana President Yoon Young-doo arrived in San Francisco from South Korea on Tuesday morning, fighting his way through a pack of journalists outside customs.
He said he will look at the efforts of airline employees to help injured passengers and their family members, visit with the NTSB and other organizations to apologize for the crash and try to meet injured passengers.
Yoon said he can't meet with the Asiana pilots because no outside contact with them is allowed until the investigation is completed.
More than 180 people aboard the plane went to hospitals with injuries. But remarkably, more than a third didn't even require hospitalization.
The passengers included 141 Chinese, 77 South Koreans, 64 Americans, three Canadians, three Indians, one Japanese, one Vietnamese and one person from France.
South Korea officials said 39 people remained hospitalized in seven different hospitals in San Francisco.
The flight originated in Shanghai, China, and stopped over in Seoul, South Korea, before making the nearly 11-hour trip to San Francisco.
