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Crashed SF jet flying too slow, NTSB reveals


An Air Canada jet passes the wreckage of Asiana Airlines Flight 214 as it lands at San Francisco International Airport on Sunday, July 7, 2013, in San Francisco, California. Asiana Airlines Flight 214 crashed as it was landing at the airport on Saturday killing two passengers and injuring hundreds. 

By JASON DEAREN and JOAN LOWY - The Associated Press

SAN FRANCISCO (AP) - Pilots of Asiana Flight 214 were flying too slowly as they approached the airport, triggering a warning that the jet could stall, and they tried to abort the landing but crashed just a second later, the head of the National Transportation Safety Board said Sunday. The airline said the pilot at the controls had little experience flying that type of plane.

While investigators began piecing together what led to the crash, San Mateo County Coroner Robert Foucrault disclosed that he was looking into the possibility that one of the two teen passengers who died Saturday survived the crash but was run over by a rescue vehicle.

Foucrault said one of the bodies was found on the tarmac near where the plane's tail broke off. The other was found on the left side of the plane about 30 feet from where the jet came to rest.

Remarkably, 305 of 307 passengers survived the crash and more than a third didn't require hospitalization. Only a small number were critically injured.

Investigators are trying to determine whether pilot error, mechanical problems or something else was to blame for the crash. At a news conference, NTSB chief Deborah Hersman disclosed that the Boeing 777 was traveling at speeds well less than the target landing speed of 137 knots per hour, or 157 mph.

"We're not talking about a few knots," she said.

Hersman described the frantic final seconds of the flight.

Seven seconds before the crash, pilots recognized the need to increase speed, she said, basing her comments on an evaluation of the cockpit voice and flight data recorders. Three seconds later, the aircraft's stick shaker - safety equipment that warns pilots of an impending stall - went off. The normal response is to boost speed, and Hersman said the throttles were fired and the engines appeared to respond normally.

At 1.5 seconds before impact, there was a call from the crew to abort the landing.

The details confirmed what survivors and other witnesses reported: an aircraft that seemed to be flying too slowly just before its tail clipped a seawall at the start of the runway and the nose slammed down.

Pilots normally try to land at the target speed, in this case 137 knots, plus an additional 5 knots, said Bob Coffman, an American Airlines captain who has flown 777s. He said the briefing raises an important question: "Why was the plane going so slow?"



Normal procedures
The engines were on idle and the pilots were flying under visual flight rules, Hersman said. Under visual flight procedures in the Boeing 777, the autopilot typically would have been turned off while the automatic throttle, which regulates speed, would been on until the plane had descended to 500 feet, Coffman said. At that point, pilots normally would check airspeed before switching off the autothrottle to continue a "hand fly" approach, he said.
There was no indication in the discussions between the pilots and tower that there were problems with the jet.

The airline said Monday in Seoul that the pilot at the controls had little experience flying that type of plane and was landing one for the first time at that airport.

Asiana spokeswoman Lee Hyomin said that Lee Gang-guk was trying to get used to the 777 on Saturday. She said the pilot had nearly 10,000 hours flying other planes but only 43 hours on the 777.

Among the questions investigators are trying to answer was what, if any, role was played by the deactivation of a ground-based landing guidance system because of airport construction. Conditions Saturday were nearly perfect, with a sunny sky and light wind.

The flight originated in Shanghai, China, then stopped in Seoul before making the nearly 11-hour trip to San Francisco. The South Korea-based airline said four South Korean pilots were on board, three of whom were described as "skilled."

Among the travelers were citizens of China, South Korean, the United States, Canada, India, Japan, Vietnam and France. There were at least 70 Chinese students and teachers heading to summer camps, according to Chinese authorities.

Fei Xiong, a Chinese passenger, was traveling to California so she could take her 8-year-old son to Disneyland. The pair was sitting in the back half of the plane. Xiong said her son sensed something was wrong.

"My son told me: 'The plane will fall down, it's too close to the sea,' " she said. "I told him: 'Baby, it's OK, we'll be fine.' "

When the plane hit the ground, oxygen masks dropped, said Xu Da, a product manager at an Internet company in Hangzhou, China, who was sitting with his wife and teen son near the back. He said he could see sparking, perhaps from exposed wires.

He turned and could see the tail where the galley was torn away, leaving a hole through which they could see the runway. Once on the tarmac, they watched the plane catch fire, and firefighters hose it down.

"I just feel lucky," said Xu, whose family suffered some cuts and neck and back pain.

Eager to escape
In the chaotic moments after the landing, when baggage was tumbling from the overhead bins and people all around her were screaming, Wen Zhang grabbed her 4-year-old son, who hit the seat in front of him and broke his leg.
Spotting a hole at the back of the jumbo jet where the bathroom had been, she carried her boy to safety.

"I had no time to be scared," she said.

Authorities closed the airport and rescuers rushed in. A United Airlines pilot radioed the tower, saying: "We see people ... that need immediate attention. They are alive and walking around."

"Think you said people are just walking outside the airplane right now?" the controller replied.

"Yes," answered the pilot. "Some people, it looks like, are struggling."

At the crash scene, police officers tossed knives to crew members in the burning wreckage so they could cut away passenger seat belts. Passengers jumped down emergency slides, escaping the smoke. Some passengers who escaped doused themselves with water from the bay.

By the time the flames were out, much of the top of the fuselage had burned away. The tail section was gone, with pieces of it scattered across the runway.