WASHINGTON -- The nation's worst train wreck in decades occurred just seconds after a towboat pilot, lost in a predawn fog, mistook a railroad bridge for another towboat with barges.
The pilot inadvertently rammed the bridge as Amtrak's Sunset Limited was bearing down on the damaged span, federal investigators believe.
The bridge collapsed as the train sped onto it, the investigators said, causing three engines and four cars to plunge into Big Bayou Canot near Mobile, Ala., at 2:50 a.m. on Sept. 22, killing 47 people.
The sequence of events, included in a report issued by the National Transportation Safety Board, occupied a much narrower time period than previously disclosed.
Earlier accounts suggested that 12 minutes elapsed from the time the bridge was struck until the crash occurred.
According to the report, the towboat pilot, Willie Odom, told investigators "he felt a thud" and then "heard a 'swoosh' sound from left to right, and saw fire seconds later."
Recreating the events leading up to the Amtrak crash, the towboat pilot told the federal safety officials that he believed he was operating on the Mobile River in heavy fog when radar picked up an object across the waterway that he thought was another towboat and barges.
He said he headed slowly toward the object, intending to pull alongside, when one of the six barges his boat was pushing struck the object.
The impact awakened the towboat's captain, Andrew Stabler, who was then summoned by a deckhand.
The captain took control of the vessel, saw fire erupt ahead, secured his barges and rescued seven people in the water.
Earlier reports suggested that the captain had been at the helm at the time of the collision.
Contradicting his company's version of the events surrounding the worst train wreck in Amtrak's history, Mr. Odom told the safety officials that he was lost in the fog when he entered the bayou.
Andrew Harris, general manager of Warrior and Gulf Navigation Co., the company that owns the towboat, had said that "because of the fog the vessel traveled a short distance up the Bayou Canot while attempting to tie off to the bank until the fog lifted."