SAN FRANCISCO (REUTERS) - The pilots aboard the Asiana Airlines Boeing 777 that crashed in San Francisco relied on automatic equipment - an auto-throttle system - to maintain airspeed and did not realize the plane was flying too slowly until it was just 60 metres above the ground, the head of the U.S. National Transportation Safety Board said on Tuesday.
In her third detailed briefing on Saturday's crash that killed two Chinese passengers and injured more than 180 other people, NTSB Chairwoman Deborah Hersman also said two flight attendants were ejected from the plane after its tail hit a seawall in front of the runway and was torn off. Both were found injured but alive on the side of the runway.
Ms Hersman said many questions remained about the incident. The South Korean airline's flight crew members were not tested for drugs or alcohol after the crash, a requirement for pilots of U.S.-based carriers involved in accidents, she said.
The accounts given to investigators by the pilots, as relayed by Ms Hersman, confirmed information from the plane's flight data recorder that showed the plane was travelling 25 percent below its target airspeed as it came in for landing.
While she has declined to speculate on the cause of the crash, much of the information released by the NTSB suggests pilot error as a main focus of the investigation.
The pilot in charge of landing the plane on Saturday was in training on the 777 and was roughly halfway through the process, while seated next to him was a co-pilot on his first flight as an instructor. Both were experienced pilots, although they had not flown together before, Ms Hersman said.
Hersman did not comment on whether anyone in addition to the two flight attendants was ejected from the plane, though the two teenage Chinese students who died were found outside the aircraft. One of them may have been run over by an emergency vehicle, San Francisco fire department officials have said, but the local coroner has not yet released autopsy results showing the cause of death.
Hersman also confirmed witness accounts that at least one emergency escape chute had deployed inside the aircraft, trapping a flight attendant. The pilot who was sitting in the cabin worked to free her, Ms Hersman said.
"I saw a leg sticking out between the slide and the wall. It kept moving," passenger Eugene Rah said in an interview on Monday. He said he and a man he believed was a crew member struggled to free her, adding: "He was asking me if I had anything sharp, but these days nobody can be on board with anything sharp." She was eventually freed and hospitalized with serious injuries, Mr Rah said.