The towboat pilot whose barge struck an interstate highway bridge, killing 14 people, had slept a total of less than 10 hours in the two days before the accident, a federal investigator said Thursday.
But investigator Ken Suydam said the National Transportation Safety Board has not concluded that lack of sleep contributed to the crash Sunday morning.
A barge that was being pushed by the towboat hit the Interstate 40 bridge over the Arkansas River and knocked out a 500-foot section of the span, sending several vehicles into the water.
The towboat captain, Joe Dedmon, told authorities he blacked out just before the crash.
Dedmon had slept a total of just 9 hours after waking Friday afternoon, Suydam said. That included six hours the night before the crash, he said.
"He did not describe feelings of fatigue" during an interview Wednesday afternoon with investigators, Suydam said.
Greg Beuerman, spokesman for barge owner Magnolia Marine Transport Co., said that kind of sleep schedule was typical for Dedmon, a 61-year-old veteran captain with no previous violations.
"We clearly feel that he was rested enough," Beuerman said.
Dedmon's health records did not reveal "anything remarkable," Suydam said. The captain remained hospitalized Thursday.
Authorities awaited the results of blood tests for alcohol or drugs, Suydam said. A urinalysis conducted Sunday by Magnolia was negative for drugs but did not test for alcohol.
Meanwhile, engineers tried to figure out how to remove an 800-ton chunk of concrete hanging from the bridge without damaging the remaining roadway.
The chunk was hanging at about a 30-degree angle, clogging the navigational channel. Two engineers from California with experience repairing earthquake-damaged bridges arrived to consult.
The Coast Guard does not dictate the amount of sleep a towboat captain should have before a shift, said Lt. j.g. Natalie Magnino.
Dedmon told investigators the last thing he remembers before the crash was passing green channel buoys about a half-mile south of the bridge, Suydam said. Traveling at 6 to 7 mph, the towboat would have taken five minutes to reach the bridge, the investigator said.