As visual evidence accumulated showing signs of a runway under-shoot, the US National Transportation Safety Board says it will dispatch a team to investigate.
Flight 214 was arriving on Runway 28 Left from a 10.5h flight from Incheon International Airport near Seoul when the incident that killed at least two people aboard began to unfold.
The seven-year-old, Pratt & Whitney PW4090-powered aircraft entered final approach at an abnormally low speed of 98kt (181km/h), according to Flightaware.com. In an audio clip retrieved from LiveATC.net, the pilot reported nothing unusual as he was cleared to land on the runway that borders the San Francisco Bay.
Noah Berger/AP/Press Association Images
A self-described eyewitness identified only as "Andre" told KCBS radio in San Francisco said he watched Flight 214 approach from inside the terminal, and remarked to the person next to him that the aircraft's tail seemed unusually low as it approached the seawall in front of the runway.
"What touched the ground was not any type of landing gear. It was all plane," Andre told the radio station. "I'm not a pilot, but I'm pretty sure that shouldn't happen."
The impact caught the attention of Kelly Thompson who was nearby. She told the radio station there was a "horrible thud".
The aircraft tail separated from the aircraft aft of the pressure bulkhead as the nose of the 777-200ER bounced twice, then spun around and departed from the left side of Runway 28.
The incident created a debris field that extended from the edge of the runway apron to the remains of the main fuselage and wings lying several hundred feet ahead.
Portions of the aircraft's tail fin and horizonal stabilisers are strewn on the runway apron.
The aircraft, registered as HL7742, was delivered on 7 March 2006, and had accumulated 35,700h on 5,185 cycles as of 31 March, Flightglobal Pro online database shows. The 777-200ER, one of 12 in the Asiana fleet, was powered by the Pratt & Whitney PW4090 engines.
Early social media updates by California firefighting agencies indicated that all 303 aboard survived the crash, but local news outlets later reported two confirmed fatalities. It was not immediately clear if the fatalities involved the passengers or crew.
[Updated at 17:47 ET to reflect new information on fatalities.]