A day after Asiana Airlines flight 214 crashed upon landing at San Francisco International Airport, stranded travellers are experiencing long lines and cancelled flights as the airport continues to operate with only two runways for departures and arrivals.

Reuters/San Francisco

US officials examined flight information recorders and began investigating the crash of an Asiana Airlines Boeing 777 that burst into flames upon landing in San Francisco, killing two teenaged Chinese students and injuring more than 180 people, officials said yesterday.

There was no immediate indication of the cause of Saturday’s accident but Asiana said mechanical failure did not appear to be a factor. The airline declined to blame either the pilot or the San Francisco control tower.

Eric Weiss, a spokesman for the National Transportation Safety Board, said the plane’s “black boxes” - the cockpit voice recorder and flight data recorder - had been recovered and were sent to Washington for analysis. The Federal Aviation Administration also was investigating and Asiana Airlines said yesterday that Korean accident investigators were on their way to San Francisco.

A component of the airport’s instrument landing system that tracks an incoming airplane’s glide path has been out of service in recent weeks due to scheduled construction and was not working on Saturday, an airport spokesman confirmed.

Pilots and air safety experts said the glide path technology was far from essential for a safe landing in good weather, but would likely be a subject of the inquiry.

NTSB Chairman Deborah Hersman said yesterday there was no indication of a criminal act but it was too early to determine what went wrong.

“Everything is still on the table,” she said on NBC’s Meet the Press.

Six people remained in critical condition at San Francisco General Hospital yesterday, including one girl, a hospital spokeswoman said, and 13 others were in less serious condition. Stanford Hospital said late Saturday that three people were in critical condition and 10 in serious condition there.

At least five people were still being treated at other area hospitals yesterday morning.

Some of the injured at San Francisco General suffered spinal fractures, including paralysis, and others had head trauma and abdominal injuries, according to Margaret Knudson, chief of surgery at the hospital.

At least two patients also suffered “severe road rash suggesting they were dragged,” Knudson said. The injured patients who were able to talk said they were all sitting in the back of the plane, Knudson said.

The plane was coming in from Seoul when witnesses said its tail appeared to hit the approach area of a runway that juts into San Francisco Bay. One witness said the plane appeared to be coming in too low and too fast.

The impact knocked off the plane’s tail and the aircraft appeared to bounce violently, scattering a trail of debris and spinning before coming to rest on the tarmac.

Benjamin Levy, a 39-year old venture capitalist from San Francisco who sat in a window seat near one of the wings, said the flight crew gave “no indication whatsoever” that there was any problem with the landing moments before the aircraft struck the runway.

Following the initial collision, “we’re going back up and I’m thinking maybe we’re taking off again. We didn’t and we went back pretty hard and bounced,” he told reporters after being released from San Francisco General.

“It’s like a Six Flags show,” he said. “We were skipping on the runway.”

Thomas O’Connor, president of the San Francisco Fire Fighters union, said he was told the first crews on the scene encountered the plane already in flames. “They pulled up and ran onto the plane, and they unbuckled and pulled out at least 7 people,” O’Connor said.

Pictures taken by survivors showed passengers hurrying out of the wrecked plane, some on evacuation slides. Thick smoke billowed from the fuselage and TV footage later showed the aircraft gutted and blackened by fire. Much of its roof was gone.

Interior damage to the plane also was extreme, Hersman said on CNN.

“You can see the devastation from the outside of the aircraft, the burn-through, the damage to the external fuselage,” she said. “But what you can’t see is the damage internally. That is really striking.”

The dead were identified as Ye Meng Yuan and Wang Lin Jia, both 16-year-old girls and described as Chinese nationals who are students, Asiana Airlines said. They had been seated at the rear of the aircraft, according to government officials in Seoul and Asiana, and were found outside the airplane.

The crash was the first fatal accident involving the Boeing 777, a popular long-range jet that has been in service since 1995. It was the first fatal commercial airline accident in the US since a regional plane operated by Colgan Air crashed in New York in 2009.

“For now, we acknowledge that there were no problems caused by the 777-200 plane or (its) engines,” Yoon Young-doo, the president and CEO of the airline, told reporters yesterday at the company headquarters on the outskirts of Seoul.

Asiana said the flight, which had originated in Shanghai, had carried 291 passengers and 16 crew members. The passengers included 141 Chinese, 77 South Koreans, 64 US citizens, three Indians, three Canadians, one French, one Vietnamese and one Japanese citizen.

Many injured paralysed; suffer head, internal wounds

Doctors at a San Franscisco hospital said yesterday the most severely injured from a Asiana Airlines plane crash a day earlier are paralysed, unconscious or dealing with serious abdominal bleeding.

Many of the most critical cases were taken to San Francisco General Hospital, where doctors saw “large amounts of abdominal injuries, a huge amount of spine fracture, some of which include paralysis, and head trauma and multiple type of orthopedic injuries,” Margaret Knudson, interim surgery chief at the hospital, said.

Two patients “had severe road rash, suggesting they were dragged. Not sure if those patients were outside of the plane and this is what happened to them but both of those patients are alive,” she told reporters at a press conference.

All of the patients who were able to speak told doctors they had been sitting in the back of the jet, where the tail broke off, as the plane smashed into the end of the runway, Knudson said.

Not everyone has regained consciousness, she added.

“Of the patients in the hospital, 15, 16,” are still unconscious, she said, saying the most critical cases are the ones with head trauma or with major abdominal bleeding.

“Some of our patients have been operated on twice already, and there’s going to be many many more surgeries to come still.”

But the surgeon said the hospital had expected to see major burn injuries, which did not appear.