The pilot who, literally, wrote the book on mountain flying has died in the March 17 crash of his Cessna 180. Sparky Imeson's Mountain Flying Bible is considered the best of several books on the subject by the veteran pilot, who was flying solo when he crashed. Investigators are still trying to determine what caused the accident about 18 miles from his departure point, Bozeman, Montana. Imeson was headed for Helena, Montana, about an hour's flying time away from Bozeman. When he did not arrive, a search was launched. The burnt wreckage of his Cessna was discovered on March 19 with his body inside. The crash site was near the location of a June 2007 crash in the Elkhorn Mountains that Imeson survived along with another pilot.