Investigators from the National Transportation Safety Board have talked to all four of the pilots who were on board Asiana flight 214 that crashed Saturday in San Francisco.
Investigators will use that testimony along with pictures, eye witness accounts and other evidence to help determine why the plane crashed.
"We are talking to the cabin crew and the flight crew as well as the surviving passengers to understand what was going on," said NTSB Chairman Debbie Hersman.
Key to their investigation is interviewing the pilot who was at the controls when the plane crashed.
"He had completed about 10 legs and 35 hours flying the triple seven, so he was half way through his operating orientation," said Hersman.
Early on NTSB investigators determined low airspeed was a major factor behind the crash.
The plane was traveling at 103 knots. This is much lower than the minimum 137 knots needed to make a safe landing.
"They had set speed at 137 knots and he assumed the auto throttles were maintaining speed. We will not determine probable cause while we are on scene that will come after we have collected all of the evidence and analyzed it," said Hersman.
The CEO of Asiana Airlines' arrived in San Francisco this afternoon.
He will work with investigators to learn more about what may have led to the crash.
And meet with survivors and their families.
The NTSB chairwoman tells us the salvage crew is working quickly to get the runway cleared the airport back to 100 percent.