Incident Overview
A private pilot reported to a fixed base operator (FBO) that the green landing gear light had not illuminated, though the mechanical indicator showed the nose gear extended. To verify the landing gear position, the pilot flew the twin-engine airplane over the runway, passing by the FBO where two pilot-rated witnesses could observe the aircraft.
Witness Observations
The two witnesses stated that the airplane flew by at a "very slow airspeed" and that the landing gear appeared to be in the extended position. They then observed the airplane initiate a climb and a gradual turn to the left. The witnesses reported hearing "a small amount of power being added to the engines, but not full power." Both witnesses remarked that the "engines sounded good and the airplane appeared to be under control."
Other witnesses south of the accident site reported seeing the airplane climbing and then turning to the left. The airplane was described as making a steep turn to the left, followed by a spin to the ground.
Aircraft Configuration
The airplane was equipped with vortex generators, which lower the aircraft's stall speed. These had been installed nine days before the accident. No pre-accident anomalies were identified during the examination of the airplane and its engines. The landing gear actuator was found in the extended position, consistent with the witnesses' observations.
Pilot Training
The pilot's flight instructor noted that the pilot "had not practiced stalls recently" and had not practiced stalls in the airplane since the vortex generators were installed. The instructor added that the pilot had never practiced full stalls in the airplane.