Nathan Ansley heard the rumbling, but it wasn’t until he and other members of the Sigma Phi Epsilon fraternity heard the sound of the dying motor of the Topeka Police Department’s Robinson R-44 helicopter that they ran outside.”At first it sounded like a car backfiring,” said Ansley, a junior accounting major at Washburn University, who added that the crash brought nearby residents streaming out of their residences to see the commotion.Initially obscured by the flashing lights of police cars, Ansley noted that at first it was difficult to make-out exactly what had happened. John Warren, member of the Delta Chi fraternity, had a similar experience.”They didn’t have any lights on [the crash site], so you could just barely see the helicopter on its side,” said Warren.While Ansley said he heard from other bystanders that the pilots were able to walk away from the accident, he did not make it out in time to see the occupants of the helicopter.Todd Roberts, also a member of the Sigma Phi Epsilon fraternity was highly skeptical when he was first informed of the incident.”I was pretty reluctant to believe it was a helicopter at first,” said Roberts.Official investigation of the crash has been handed over to the Federal Aviation Administration. Wreckage from the helicopter was cleared by Saturday afternoon.