Investigators in the Bronx train derailment are poring over engineer William Rockefeller's every move before the crash -- from his breakfast choice that morning to his actions seconds before the cars left the track.
Among the many mysteries investigators hope to solve is a crucial question: Why was the train barreling down the tracks at 82 mph -- almost triple the 30-mph speed limit in that area -- before it left the curved stretch of track?
Investigators interviewed Rockefeller Monday and will continue speaking with him over the next few days as they pursue answers.
A law enforcement source said Rockefeller's statements would be compared with information from the train's data recorders.
"The data tells the story of how this happened," said the source. "It corroborates or debunks."
Investigators are looking at the 20-year MTA veteran's training and his safety record. They want to know how much sleep he got and the last time he had used his cellphone, which they are examining.
Rockefeller, 46, was tested for drugs and alcohol after the accident, but results are not yet available, said National Transportation Safety Board member Earl Weener.
To his friends and colleagues, Rockefeller is known as someone who loves his work driving trains. He has a passion for railroads, their history and the safest way to operate them, said Donald Stone, a friend and neighbor of Rockefeller in upstate Germantown.