On June 23, 1994, at 1155 central daylight time, a Hiller HU-12E, N330CW, registered to Emerald Helicopters, Inc., of Olivia, Minnesota, and piloted by a commercial helicopter pilot, experienced a wire strike and impact with the terrain while maneuvering during aerial application. The helicopter was destroyed and the pilot sustained fatal injuries. The 14 CFR Part 137 flight was operating in visual meteorological conditions. No flight plan was on file. The exact location of the departure and time of departure are unknown. The helicopter was involved in aerial application. A witness described hearing a "snap" followed by a noise that sounded like "thunder" and saw flames 30 feet high. An examination of the wreckage area revealed small pieces identified as being from the helicopter under nearby electrical transmission wires. No pre-existent mechanical anomalies were found on examination of the helicopter. There was no evidence of fire prior to impact with the terrain. A post mortem examination completed by the Department of Pathology, Prairie Lakes Health Care Center, Watertown, South Dakota, of the pilot revealed no pre-existing anomalies. The toxicological examination of specimens from the pilot were negative for ethanol and the drugs screened.