Accident Summary
During cruise flight at 27,000 feet, the airplane encountered unforecasted severe turbulence. The pilot transmitted a "mayday" call on the airplane radio to Jacksonville Center. Within seconds, the airplane accelerated from 175 knots to over 300 knots ground speed and descended from 27,000 feet to 16,500 feet. The aircraft then disappeared from radar coverage.
Wreckage Location
Sheriff Department personnel located the airplane 15 miles north of Homerville, Georgia, in a swampy area.
Examination Findings
Recovered airframe components were submitted to the NTSB Materials laboratory for examination. The examinations determined that all failures were due to overload. Further examination of the airframe indicated that the airframe design limits were exceeded.
Weather Briefing
The pilot did not obtain a weather briefing before the flight departed.
Probable Cause
The probable cause, as stated in the official findings, is an in-flight encounter with unforecasted severe turbulence in cruise flight resulting in the design limits of the airplane being exceeded due to an overload failure of the airframe, and collision with a swampy area.