Driver Fatigue and Speed Caused Fatal Bus Crash, Investigators Say

Except for a few naps, the driver of the bus that crashed last year in the Bronx, killing 15 passengers, had gotten no significant sleep in the three days leading to the wreck, federal investigators concluded on Tuesday.

In its final hearing on the crash, the National Transportation Safety Board attributed the accident to the sleep-deprived driver’s fatigue. Investigators said records from his cellphone and a car rental agency showed that the driver, Ophadell Williams, had been driving around the New York City area and talking almost continuously on his phone when he should have been resting.

The crash could have been avoided if Mr. Williams had not been so sleepy and had not been driving so fast, investigators said. They determined that the bus had been traveling as fast as it could go — 78 miles per hour — just before the crash and was going 64 m.p.h. when it veered into a guardrail on Interstate 95.

“Together, fatigue and speed are an especially lethal combination,” Deborah A. P. Hersman, the chairwoman of the safety board, said during the hearing in Washington. “This deadly accident did not have to happen.”

The board also found that the company based in Brooklyn that employed Mr. Williams — World Wide Travel of Greater New York — had not kept track of logs of his driving or maintained adequate safety controls.

Mr. Williams, who suffered minor injuries during the crash, was indicted last fall on charges of manslaughter and negligent homicide. He pleaded not guilty and has been jailed at Rikers Island on $250,000 bail since then.