Amateur-built RV4 accident near Chattahoochee, Florida, October 31, 2021

The NTSB's narrative final · quoted from the NTSB record

The pilot departed the airport for a cross country flight. Shortly after departure, radar services were terminated by air traffic control and the pilot was cleared for a radio frequency change. Seventeen minutes later, radar contact was lost. Automatic dependent surveillance-broadcast data obtained from the Federal Aviation Administration revealed the airplane climbed to about 2,500 ft mean sea level and made a few turns to the north and northeast before heading northwest. The airplane began to lose groundspeed, turned to the left and descended, then gained groundspeed as it continued to descend. The last data track showed the airplane at 650 ft and a groundspeed of 172 knots. A witness was outside at his house when the canopy from the airplane fell in his yard. The canopy was about 1.5 miles away from the main wreckage. The accident site was in a wooded area and the wreckage path was about 550 ft long. The airplane was heavily fragmented and scattered along a debris path. The canopy handle was found in the open position with the looking pin damaged and bent at its tip. It is likely that the canopy was not locked correctly before takeoff and that it opened in flight and departed the airplane. The airplane then made a gradual slow left descending turn and continued to gain airspeed until it contacted trees and the ground at a high rate of speed. Based on the available evidence, it could not be determined if the canopy contacted and incapacitated the pilot when it separated from the airplane, which then resulted in a loss of control.

The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.