Accident Overview
On April 7, 2008, at 1701 eastern daylight time, a Czech Aircraft Works SPOL SRO CH 601 XL RTF, registration N357DT, was substantially damaged after impacting trees and terrain following an uncontrolled descent near Polk City, Florida. The certificated private pilot, who was the owner, sustained a fatal injury. Visual meteorological conditions prevailed, and no flight plan was filed for the personal flight conducted under 14 Code of Federal Regulations Part 91. The flight originated from Williston Municipal Airport (X60), Williston, Florida, and was destined for Lakeland Linder Regional Airport (LAL), Lakeland, Florida.
Witness Observations
A friend of the accident pilot, who shared a hangar at Lumpkin County Airport (9A0) in Dahlonega, Georgia, reported that both planned to fly to an air show in Lakeland. The accident pilot departed 9A0 about 1240, and the friend departed about 1300. The friend landed at X60 for a fuel stop and later spoke with the accident pilot around 1500 as he approached X60, noting the airplane was "running fine." Fuel receipts indicate the pilot purchased fuel at X60 at 1607.
FAA radar data showed a target correlated to the accident airplane departing Williston at 1614, proceeding southeast with a transponder code of 1200 but no altitude data. Transponder transmissions ceased about 1620, leaving only primary radar returns. The final radar target was observed at 1701 near where the wreckage came to rest.
A witness about half a mile southeast of the accident site observed the airplane approaching from the north at a noticeably lower altitude. The airplane exhibited a series of shallow banks before the right wing "folded up" and the airplane entered a nose dive. The engine sound changed, indicating overspeed. Another witness about a third of a mile west heard a "pop" and saw the right wing folded back as the airplane spun down.
Aircraft and Pilot Information
The pilot held a private pilot certificate with a single-engine land rating. His most recent FAA second-class medical certificate was issued on February 29, 1980. Logbook records showed 514 total flight hours, with 71 hours in the accident airplane make and model. The pilot had recently resumed flying after purchasing the airplane in October 2007.
The accident airplane, manufactured in 2005, was classified by the FAA as a Special Light Sport Aircraft. Its most recent annual conditional inspection was completed on September 1, 2007, at 142 total hours of operation.
Wreckage Examination
The wreckage came to rest in a heavily wooded area. No evidence of pre- or post-impact fire was found. The fuselage was buried in a 6-foot-deep crater, with the forward section destroyed by impact forces. The left wing was bent upward 90 degrees at the side of the body, with the lower spar chord fractured and deformed. The right wing remained intact but showed impact damage. All movable control surfaces were identified, and control cable continuity was confirmed from the cockpit to the rudder, elevator, and ailerons. The aileron trim tab was found at the full trailing edge down position. Both fuel tanks were ruptured and absent of fuel, with the fuel selector in the "left" position. The engine exhibited crankshaft and valvetrain continuity; all three composite propeller blades were separated near the hub.
Additional Information
Toxicological testing by the FAA detected no ethanol or drugs. An autopsy determined the cause of death as blunt impact.
The left wing spar was examined at the Safety Board Materials Laboratory. The spar components were consistent with 6061-T6 aluminum alloy. Fracture surfaces showed overstress separation with no evidence of fatigue cracking. The design and analysis documentation for the CH 601 XL indicated that the airplane met ASTM requirements for limit loads but may not have fully met the 6g ultimate load requirements.