Accident Overview
A flight instructor and a private pilot/owner departed from their home airport to conduct a biennial flight review. According to radar data, the airplane climbed to 3,400 feet mean sea level (msl) and began maneuvering between 3,500 and 3,800 feet at groundspeeds of 109 to 131 knots. As the maneuver continued, the speed gradually decreased from 101 knots to 65 knots while the altitude descended from 3,700 to 2,800 feet. During this descent, the airplane entered a spin and continued spinning until it impacted the ground.
Pilot Experience and Medical History
The private pilot had approximately 1,207 total flight hours, all of which within the previous six years were accumulated in the accident airplane. The flight instructor reported over 10,800 total flight hours. The private pilot had experienced a heart attack three years prior to the accident and had received Special Issuance Medical Certificates from the FAA on three occasions afterward. Approximately ten months before the accident, the pilot developed intermittent atrial fibrillation and began taking warfarin, a blood thinner, to reduce stroke risk. The pilot's FAA medical records did not note any symptoms associated with the atrial fibrillation or its frequency. Information submitted to the FAA indicated the pilot was on an inadequate dose of warfarin to effectively reduce stroke risk. Nevertheless, the FAA most recently authorized a Special Issuance medical certificate two months before the accident.
Aircraft Examination
Examination of the airplane and engine revealed no preimpact mechanical anomalies.