Two flight attendants at the back of Asiana Airlines Flight 214 were ejected but survived when the plane slammed into a seawall and lost its tail during a crash landing at San Francisco's airport, according to officials from the National Transportation Safety Board.
Both women were found on the runway, amid debris.
In a news conference Tuesday, NTSB officials didn't explain fully why the plane approached the notoriously difficult landing strip too low and slow, likely causing the crash, although they did quote testimony from one of the pilots that explained more about what occurred moments before Flight 214 crash landed.
NTSB Chairwoman Deborah Hersman said the pilot at the controls was only about halfway through his training on the Boeing 777 and was landing at the San Francisco airport for the first time.
Hersman also said his co-pilot was on his first trip as a flight instructor.
The NTSB hasn't ruled anyone at fault in the crash, with Hersman saying that probable cause will not be determined on scene.
Audio recordings show the pilots tried to correct the plane's speed and elevation until only seconds before hitting the seawall at the end of the runway, an impact that sent the fuselage bouncing and skidding across the airfield.
The pilots told the National Transportation Safety Board that the auto-throttles were set to maintain 137 knots, which is faster than the plane was travelling at its approach.
Here is what is known: Seven seconds before impact, someone in the cockpit asked for more speed after apparently noticing that the jet was flying far slower than its recommended landing speed. A few seconds later, the yoke began to vibrate violently, an automatic warning telling the pilot the plane was losing lift and in imminent danger of an aerodynamic stall. One and a half seconds before impact came a command to abort the landing.
Hersman said at the news conference that the instructor realized the craft was coming in too low by the time the plane went below 500 feet. This was indicated by the Precision Approach Path Indicators (or PAPIs) situated on the runway, which were showing three red lights out of four. A normal approach would show two red lights and two white, with more reds than white indicating the plane is too low, while more whites than red indicate a plane is coming in too high.
By the time Flight 214 reached 200 feet, the PAPI’s were all red, indicating that the aircraft was perilously low, according to the instructor’s reported testimony. He also stated that the auto-throttle had not maintained the necessary speed.
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.
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 has 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.
Investigators want to nail down exactly what all four pilots were doing at all times.
On Tuesday, Hersman said that at the time of the crash, three pilots were in the cockpit, while the fourth was in the cabin. Hersman added it was not necessary for all four pilots to be in the cockpit during landing.
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 and try to meet injured passengers.
Coroner Robert Foucrault told The San Francisco Chronicle on Tuesday that investigators told the parents of 16-year-old Ye Meng Yuan that she was the girl who may have been been struck and killed accidentally on the runway by a fire truck racing to the scene of the crashed plane.
Ye's parents flew into San Francisco International Airport late Monday along with the parents of the other girl killed in Saturday's crash, Ye's close friend Wang Lin Jia, also 16.
The police department's hit-and-run unit is investigating Ye's death.
The Associated Press contributed to this report.