Incident Sequence
On December 5, 2005, at approximately 16:45 local time, a Beechcraft F33A aircraft, registration EC-FXZ, operated by Centro de Formación Aeronáutica AEROFAN, S. L., was conducting a visual navigation training flight from Cuatro Vientos Airport to Robledillo de Mohernando aerodrome in Guadalajara. The aircraft was crewed by an instructor pilot (pilot in command) and a student pilot. The flight included practice touch-and-go landings at Robledillo.
According to the instructor's report, the fourth landing was planned as a full-stop landing. The student initiated the approach after confirming three green landing gear indicator lights. The landing itself was normal, with no floating after touchdown. However, when the student began braking, a metallic scraping noise was heard. The aircraft continued a few meters before the landing gear collapsed, causing the propeller to contact the runway surface. The engine stopped, and the aircraft slid further before coming to rest. The crew shut off fuel and electrical power and exited the aircraft unassisted.
Damage Assessment
The three propeller blades were bent backward at their tips, with evidence of ground contact. Both flaps showed slight deformation, particularly the left flap. The main landing gear doors had significant damage to their outer edges, likely from scraping. Several retraction system rods were buckled, and the electric motor's winding was burned. The damage to the lower fuselage was minor, and the nose gear doors were only slightly affected.
Weather Conditions
At the time of the incident, there were scattered clouds, full visibility, and no wind gusts.
Investigation Findings
Examination of the landing gear system revealed that the electric motor's winding was burned, suggesting that electrical current was not interrupted and the motor was subjected to overload. This could occur if the torque link lever did not reach the limit switch, preventing the motor from stopping. Such a condition might arise if the wheels contacted the runway before the gear was fully extended, halting the cruciform's rotation before the switch was actuated. The resulting stress from braking could then cause rod failure and gear collapse. The gear actuator components showed no breakage except for buckled rods and a burned motor. The three green lights had been illuminated, indicating that normally the gear would be down and locked, but the damage suggests the gear may not have completed its full extension cycle.