The cause of a February plane crash in Dawson County has been released in a preliminary report by the National Transportation Safety Board. According to the report, the pilot of the Ercoupe 415 had recently purchased the single engine aircraft and was reportedly flying it out of Jefferson Feb. 9 back to his home airport in LaFayette when, 30 minutes after departure, the oil pressure began dropping. The pilot attempted to turn the airplane toward Lee Gilmer Memorial Airport in Gainesville when the oil pressure decreased to zero.