With scott pelley. Pelley good evening. Late today, federal investigators said there was nothing wrong with the brakes on that metro north commuter train that derailed in new york city sunday morning killing four passengers and injuring dozens of others. They said that the brakes had been tested before and during the trains run. Yet to be answered is why the train was going nearly three times the speed limit. Its coming down to the actions of the engineer and jeff pegues, our transportation correspondent has the latest. Jeff . Reporter scott, in addition to that information about the brakes, the n. T. S. B. Revealed late today that there was no sign that any of the crew members including the engineer had used alcohol. This is n. T. S. B. Board member earle wainer earlier today. Reporter increasingly, the focus of the investigation appears to be human error. Sources say that william rockefeller, jr. , the engineer, told First Responders on sunday that before the train went off the track