Asiana Flight 214 made no distress calls and appeared to be operating smoothly moments before it slowed to a near-stall, crashed into a seawall near the runway and broke apart, a federal official said Sunday.
“There is no discussion of any aircraft anomalies or concern with the approach,” Deborah Hersman, chairwoman of the National Transportation Safety Board, said at an afternoon news conference that included reporters from all over the world.
Then, at seven seconds prior to impact, a call is heard from one crew member “to increase speed,” Hersman said. At four seconds before impact, the sound of the “stick shaker” – which noisily vibrates to warn pilots of an impending stall – can be heard, she said. Then, one and a half seconds before impact, the cockpit crew sought to initiate a “go-around,” hoping to power back up and circle back to the runway.
Asked if pilot error may have been a factor, Hersman stressed that the investigation would probably take more than a year and that “everything is on the table right now. It is too early to rule anything out.”
The cockpit voice recorder offered two clear hours of good quality and indicated that the Boeing 777 was cleared for visual approach to the 2-mile runway 28L. The flaps were configured at 30 degrees and the landing gear was down. Target speed was 137 knots and the approach “proceeds normally as they descend,” Hersman said.
But then Hersman said that during the approach, “the data indicate that the throttles were at idle and airspeed was slowed below the target airspeed.”
“The speed was significantly below 137 knots,” she said. When questioned further, Hersman said, “we’re not talking about a few knots,” but she declined to give exact speeds.
The engines appeared to be working properly. Throttles were advanced “a few seconds prior to impact and the engines appear to respond normally,” she said.
Hersman confirmed that part of the so-called glide path system that assists pilots with instrument based landings had been out of commission since June 1. The glide slope – which “can give you a constant approach to the airport on an approach down” has been sidelined until Aug. 22 due to runway construction, and all pilots had been notified.
Another part of that system – known as a localizer – that lines up an aircraft horizontally around the runway’s center line, was working correctly, a test flight revealed, she said. So were precision approach indicator lights, which were then “significantly damaged” during the crash.
Hersman said the aircraft may have also had GPS-based technology that offers vertical guidance to pilots.
The unavailability of the glide scope is part of the investigation, as is a detailed look at all the technologies the aircraft had deployed, Hersman said. But she stressed that “this was a visual approach.”
The skies were clear and wind was blowing at 7 knots, with a visibility of 10 miles. “What a visual approach means is that you can fly it visually,” she said. “You do not need instruments. It was a clear day. They were cleared for a visual approach.”
Handling of the aircraft “appeared routine until the controller noticed that the aircraft hit the seawall,” she said.
The aircraft’s engine is manufactured by Pratt & Whitney. About 168 other Boeing 777s use the same model of engine.
Hersman offered a glimpse at the far-reaching scope of the investigation and said crews should be on scene for at least a week. Korean airline safety investigators as well as Asiana’s own investigators arrived Sunday and have joined the team, and FBI evidence response and hazardous materials teams are also assisting.
The investigation includes an operations group, which will evaluate the airport geography, the cockpit instruments, seats, windshields, flight plans, training and experience of the crew, whom investigators hope to interview “in the next few days.”
“They can tell from examinations whether the engine was rotating at the time of the crash, so they will look at that, and whether any fires originated in the engines,” Hersman said.
A site survey will locate the “four corners of the wreckage” and search for key parts. Investigators are also probing the seating positions of those killed and injured, deployment of the chutes, and use of seat belts and child safety seats. They will soon interview survivors.
A separate “human performance investigator” will perform drug and alcohol testing, and probe fatigue, medication use, sleep disorders and what Hersman called “crew resource management -- how they work together and communicate.”
The NTSB is seeking video footage and photographs from eyewitnesses, which can be uploaded on its website, she said.
Speaking at a news conference in Seoul earlier Sunday, Yoon Young-doo, Asiana’s president, described the pilots involved as “skilled” and said it could take time to determine what went wrong.
The twin-engine 777 is one of the world’s most popular long-distance planes, often used for flights of at least a dozen hours.
By Saturday night, all 307 on board the Asiana flight had been accounted for, authorities said. A total of 182 people had been transported to hospitals, including 49 in serious condition. Among the passengers were 77 Korean citizens, 141 Chinese, 61 Americans and one Japanese, according to South Korea-based Asiana.
The two passengers who died were 16-year-old students from China. Asiana Flight 214 originated in Shanghai and stopped in Seoul before flying to San Francisco.
The bodies of the teens were found on the runway, said San Francisco Fire Chief Joanne Hayes-White. It was not clear whether they had been pulled from the plane or ejected.
Hospital officials said Sunday afternoon that the crash had left at least two people paralyzed with spinal injuries. Eight people remained in critical condition.
Of the 53 patients treated at San Francisco General Hospital, 34 have been discharged and 19 remained hospitalized, hospital spokeswoman Rachael Kagan said. Six of them, including one minor girl, were in critical condition, she said.
Stanford Hospital said Sunday that it treated 55 patients from the Asiana crash, admitting 11 of them. Two of those patients were listed in critical condition at noon Sunday.
An additional seven patients were taken to Packard Children’s Hospital at Stanford, officials said, and were listed in good condition Sunday.
Thousands of passengers were stranded at San Francisco International Airport after Saturday’s crash which shut down the airport’s four runways. SFO’s restaurants stayed open all night Saturday to cater to stranded travelers whose stood for hours in long lines to change their tickets.
Two runways reopened about three hours after the crash. Some international flights began leaving again Saturday night.
About 1 p.m. Sunday, a third runway, 28R, reopened, officials said on Twitter.
“Some good news!” @FlySFO tweeted. “28R is now open!”