The pilots of the Boeing 777 jet that crashed as it was coming in to land at San Francisco’s airport on Saturday, killing two teenagers, tried to abort the landing moments before the plane clipped a sea wall in front of the runway.

Drawing on data from the aircraft’s cockpit voice and flight data recorders, the head of the US National Transportation Board Deborah Hersman said on Sunday night that the pilots of Asiana Airlines flight 214 “called to initiate a go-around,” where a plane aborts a landing attempt during its final approach to the runway, just 1.5 seconds before the crash. That was after a stall warning sounded four seconds before impact.

Ms Hersman said the plane was travelling “significantly below” its target landing speed of 137 knots, or 157 miles, per hour. “We’re not talking about a few knots,” she said.

However, officials warned against drawing any firm conclusions from the preliminary findings. Earlier, Asiana Airlines appeared to rule out any mechanical failures, saying there were no problems with the Boeing 777 or its engines.

Speaking in San Francisco on Sunday, Ms Hersman said it was too early to pinpoint the cause of the crash. “What I will tell you is that the NTSB conducts very thorough investigations. We will not reach a determination of probable cause in the first few days that we’re on an accident scene,” she told reporters.

A total of 182 people were injured when the flight carrying more than 300 people crashed and burst into flames while coming into land at about 11.30am local time on Saturday, following a journey from Seoul in South Korea. At least six people remained in critical condition on Sunday.

The plane came down short of the runway, striking a sea wall as it attempted to land. The impact tore off the aircraft’s tail section and sent the fuselage spinning across the tarmac. Passengers and crew escaped down emergency slides as it burst into flames.

The two passengers who died in the crash have been identified as Chinese students Ye Meng Yuan and Wang Lin Jia, both 16. Chinese state media identified the girls as middle school students from the country’s eastern Zhejiang province.

Asiana also confirmed that, of the injured, 49 were in serious condition. Margaret Knudson, the chief of surgery at San Francisco General Hospital, where many of the injured were transported following the crash, told reporters on Sunday that at least two patients were suffering from paralysis. 19 patients were still at the hospital on Sunday.

On Saturday, pictures taken shortly after the crash showed people sliding down the aircraft’s inflatable emergency slides to safety.

Speaking to NBC, passenger Benjamin Levy said he was feeling “extremely lucky”.

Describing what happened, he said: “We were approaching perfectly well, but we were too low. When the pilot realised it, he put some more gas to correct it, but it was too late. We hit the runway pretty bad, and we started going up in the air again, and we landed pretty hard.”

Asiana is South Korea’s second-largest airline, and one of dozens of major firms with Boeing 777s in their fleets. The twin-engine aircraft has had an impeccable safety record in its 18-year history, though in 2008 a Boeing 777 landed short of the runway at London’s Heathrow. It had lost power due to icing in the fuel system – a flaw since resolved by the manufacturer. Nobody was injured.

The last major fatal crash in the US was in 2001, when American Airlines Flight 587 – an Airbus A300 – came down in Queens, New York, shortly after take-off from JFK airport, killing all 260 people on board and five people on the ground.

Crash stories

“I just crash landed at SFO. Tail ripped off. Most everyone seems fine. I’m ok. Surreal.”“Fire and rescue people all over the place. They’re evacuating the injured. Haven’t felt this way since 9/11…” - David Eun @Eunner Samsung executive, survivor

“I know the airport pretty well, so I realised the guy was a bit too low, too fast, and somehow he was not going to hit the runway on time, so he was too low… He put some gas and tried to go up again … but it was too late so we hit the runway pretty bad…” - Benjamin Levy, survivor

“The plane came in at a bad angle, the tail clipped the runway… It went through quite a few acrobatics on the runway… The tail was too low. Instead of coming in flat, it was coming in at I’d say a 45 degree angle.” - Stephanie Turner, witness

“It got unsteady and one wing caught on the runway and just crashed.” - Danielle Wells @DanielleLWells, witness

“There was a fireball that came out from underneath the plane. Then the plane started to lift and cartwheel.” - Anthony Castorani, witness

“Our flight was scheduled to come in at the same time, but we were early and landed about 20 minutes before the crash.” - Sheryl Sandberg, Facebook chief operating officer