Cessna 172 RG EC-HYT Runway Excursion at Seguntino Aerodrome

Incident Overview and Flight Details On Saturday, May 14, 2005, at 16:35, a Cessna 172 RG with registration EC-HYT, operated by American Flyers, departed Cuatro Vientos Airport for a local dual-instruction flight. The aircraft was powered by a single Lycoming O-360 F46 engine. Aboard were a 24-year-old commercial pilot instructor with 696 total flight hours and 82 hours on type, a student pilot, and one passenger. ## Unplanned Landing and Fuel Imbalance During the flight, the crew observed a significant fuel consumption imbalance, with the left tank depleting much faster than the right. This caused noticeable aircraft destabilization due to weight differences. The crew decided to land at a nearby ultralight aircraft runway near Sigüenza, Guadalajara. The landing was uneventful. ## Takeoff Attempt and Runway Excursion After transferring fuel to the right tank, the crew attempted to resume the flight. The runway was approximately 400 meters long, paved, and had a noticeable downhill slope. During the takeoff roll, at approximately 40 knots and past the halfway point of the runway, the instructor, who was at the controls, noticed the nose of the aircraft descending toward the runway. The aircraft subsequently veered to the right and came to a stop at the right edge of the runway. All occupants evacuated the aircraft unassisted. ## Damage and Investigation Findings The aircraft sustained minor damage, primarily to the nose wheel compartment door, and the propeller was deformed backward at its tips after striking the runway. The nose wheel was found retracted. Post-accident functional tests showed the landing gear mechanism operated correctly, and the fuel system had no issues. A total of 110 liters of fuel was recovered, with similar quantities in both tanks. ## Contributing Factors The investigation indicated the abnormal fuel consumption in the left tank was likely due to excessive ventilation, possibly caused by improper assembly or displacement of the ventilation tube at the wing joint. Regarding the nose gear retraction, the mechanism functioned properly, but the takeoff was marginal given the short runway length and elevation of 1,070 meters. The investigation concluded that an inadvertent movement of the landing gear lever was a possible cause, as the gear warning lights indicated the gear was in transit (amber) when the master switch was connected during post-accident checks.