What happened
On September 24, 2022, a Piper PA-18-150, registration CX-BOT, was performing glider towing instruction and training at the La Alameda Aerodrome (SUSC) in Maldonado, Uruguay. The aircraft had just completed its second towing flight of the day and had landed on runway 06.
As the pilot attempted to taxi toward the parking area, the aircraft performed a standard right-hand turn. For a conventional gear aircraft, this maneuver involves applying a small amount of power and adjusting the elevator to manage aerodynamic pressure. During this turn, a tailwind gust lifted the tail of the aircraft, causing the pilot to lose control. The aircraft subsequently struck the ground on its nose with the engine running at idle. The impact caused the propeller blades to bend and the lower cowling to sustain minor damage. The pilot, who was the sole occupant, was uninjured and able to exit the aircraft independently.
The investigation
The CIAIA investigation examined the environmental conditions, the aircraft's mechanical state, and the regulatory framework governing the operation. Investigators noted that the aerodrome is located in a natural depression in the terrain, which can create orographic turbulence and microclimates. This was confirmed by observations that wind conditions at the site differed from the official METAR reports from the nearby Laguna del Sauce Airport.
Technical analysis of the aircraft showed that all documentation was up to date, though the aircraft lacked an identification plate at the time of the event. The investigation also reviewed the pilot's credentials, noting they held a valid commercial license and sufficient experience for the task, though the specific regulatory requirements for glider towing instructors were found to be lacking in the local framework.
Findings
- A tailwind gust acted as a contributing factor by lifting the tail and inducing a loss of control during the ground maneuver.
- The local topography at La Alameda creates a microclimate prone to sudden changes in wind direction and intensity.
- The operator was providing flight instruction without being formally structured as a Civil Aviation Training Center (CIAC), meaning they were not required to implement a Safety Management System (SMS).
- There was a lack of written procedures for the towing operations performed by the operator.
- The existing regulatory framework did not specifically provide for a dedicated glider tow pilot or instructor rating.