The National Transportation Safety Board is investigating a fatal Sunday afternoon helicopter wreck in Cottle County, said County Emergency Management Coordinator Randy Detwiler. “NTSB had (conducted) a preliminary investigation but they didn’t make an official determination” on the cause of the wreck, Detwiler said by phone Monday evening. NTSB public affairs employees have been furloughed due to the government shutdown and could not be reached for comment. read more