LIVE VIDEO ? The National Transportation Safety Board holds a media briefing on its investigation into the crash of Asiana Flight 214 in San Francisco.
By M. Alex Johnson, Staff Writer, NBC News
Crew members twice called to abort the landing of Asiana Flight 214 in the last 5 seconds before it crash-landed at the San Francisco airport last weekend, federal investigators said Thursday.
It was previously reported that the crew tried to abort the landing in the last few seconds before the crash Saturday at San Francisco International Airport. But Deborah Hersman, chairman of the National Transportation Safety Board, revealed in a briefing for reporters Thursday that there was also a second call for a "go-around" ? abandoning the landing attempt.
Why the plane clipped a seawall at the airport remains a mystery. Hersman said reviews of the automated pilot system, the automated throttles and the flight director systems all showed "no anomalous behavior."
Officials said debris from the airliner has been cleared from the runway, which could reopen as soon as Sunday.
Hersman said the NTSB has returned the runway to the jurisdiction of officials at San Francisco International Airport, but she said a grassy area where the fuselage of Asiana Airlines Flight 214 remained under NTSB control.
Doug Yakel, a spokesman for the airport, told NBC News it would probably take a few days before Runway 28 Left was operational again, which could be late Sunday or early Monday.
Two Chinese teenagers were killed and about 180 other passengers were injured when the Boeing 777 crashed. Seventeen people remained in area hospitals Thursday, three of them ? two adults and a child ? in critical condition.
Hersman was briefing reporters Thursday afternoon on the NTSB investigation, which is trying to answer several questions. She previously answered one of those Thursday ? telling NBC Bay Area that a flash of light the pilot reported having seen about 34 seconds before the crash wasn't a laser.
Hersman said at the briefing that the light, which could have been a reflection of the sun, didn't affect the pilot's vision.
Lasers pointers have become a significant problem for pilots, said the Federal Aviation Administration, whose records reflect an 800 percent rise in the number of such incidents from 2006 to 2012, the last year for which full figures are available. Pointing them at airplanes "can completely incapacitate pilots," it said, and it's a federal crime.?
Another mystery is why the plane wasn't immediately evacuated. Hersman said Wednesday that the doors weren't opened until about 90 seconds after the plane had come to a full stop. The standard is to have the plane fully evacuated within 90 seconds.
It also remains unclear why the plane's evacuation chutes prematurely opened inside the cabin on the plane's second impact ? they're supposed to open outward.?
Audio of 911 calls from passengers and witnesses after Asiana Airlines Flight 214 crashed Saturday in San Francisco.
And investigators also want to know why flight data indicated that the plane's automated systems recorded multiple "autopilot and autothrottle modes" as it approached San Francisco.
"There is automation there to support the pilots, but pilots also have to fly the airplane," Hersman told NBC News on Wednesday. "They have to monitor, and they have to fly."
Separately, emergency agencies were defending their response to the crash after recordings of passengers' and witnesses' calls to 911 reflected frantic concern that there weren't enough emergency crews on the scene.
Related: 'We're trying to keep her alive': 911 calls reveal drama of Asiana crash
Fire officials told NBC's TODAY that ambulances responded within 13 minutes and that private ambulances were already on the scene. The incident commander initially told them to keep away from the plane because of fears it could explode, they said.
A spokesman for American Medical Response, which provides ambulance services in 42 states, said ambulances had gone to a staging area before continuing to the wreckage in groups of five in accordance with a crash response plan.
Tom Costello and Ami Schmitz of NBC News contributed to this report.
Related:
Why don't planes have safer seat belts? Cost and comfort
Pilot in charge of Asiana flight was on his first trip as an instructor: NTSB
This story was originally published on Thu Jul 11, 2013 4:51 PM EDT
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