What happened
On February 19, 2004, at approximately 12:55 local time, a Bucker/CASA 1131, registration EC-FSI, departed from Reus Airport for a private local flight. The aircraft was operated for general aviation purposes, specifically for instruction and familiarization. After 30 minutes of flight, the pilot attempted to land on runway 25 under favorable weather conditions and calm winds.
During the landing roll, the aircraft initially appeared to be on a normal trajectory; however, upon contact with the runway, the aircraft veered to the left. The pilot attempted to correct the deviation using engine and aerodynamic controls, but the aircraft exited the paved surface. As the aircraft traveled across the grass area, it crossed a fire access road and entered a section of tall grass measuring between 40 and 50 cm. The aircraft then encountered a ground depression or step of more than 10 cm in height. The right landing gear struck this uneven terrain, causing the right wing to strike the ground and resulting in the aircraft overturning. The pilot and one passenger sustained minor injuries, while the aircraft suffered significant damage to the propeller, right landing gear, rudder, right wing underside, and nose.
The investigation
The investigation examined the runway conditions and the physical characteristics of the area surrounding the paved surface. It was noted that the asphalt surface at the touchdown zone exhibited undulations. Furthermore, the area immediately adjacent to the runway lights consists of mowed grass, followed by a fire access path and then a zone of much taller, uncut grass. The investigators also identified a significant unevenness in the terrain, specifically a 10 cm vertical drop, which the right gear encountered.
Findings
- The aircraft's deviation from the runway centerline may have been triggered by the undulations in the asphalt surface or the specific nature of the tailwheel contact during touchdown.
- The aircraft's excursion into the tall grass and its subsequent overturn were facilitated by the slope of the terrain and the impact with a ground depression.
- The incorrect execution of the landing maneuver was identified as the primary factor in the loss of ground control.