A man who died in a plane crash in Calaveras County last week was on his third test flight in the self-built plane when it went into a tail spin, the Calaveras County Sheriff's Office reported Wednesday.
Russell Hackler, 68, was test flying the single-engine amphibious plane at the Calaveras County-Maury Rasmussen Field with his 38-year-old son on Nov. 23. Hackler's son was on the ground when he saw his father's plane start to spin toward the ground and then saw the right wing start to tear away from the fuselage.
The plane went out of his sight when it crashed in a field east of Highway 49 and about ¾ of a mile south of the airport.
The exact cause of the crash has not been determined and is under investigation by the Federal Aviation Administration and the National Transportation Safety Board.
It is expected that it will take several weeks before a cause of the crash is determined. Hackler was reportedly an experienced pilot.