What happened
On October 12, 2023, at approximately 19:40 UTC, a Piper PA-11, registration LV-YPF, was involved in a ground loss of control accident at Aeródromo Juárez, Buenos Aires. The aircraft, operated by Aeroclub Benito Juárez, was conducting a general aviation training flight.
After 50 minutes of flight under visual meteorological conditions, the pilot completed a successful touchdown on runway 18. While decelerating at a very low speed and preparing to initiate a 180-degree turn to clear the runway, an uncommanded movement caused the tail of the aircraft to lift. This motion resulted in the propeller striking the ground, causing an immediate engine stoppage and damage to the propeller, cowling, oil pan, and air filter. The pilot was uninjured and exited the aircraft safely.
The investigation
The investigation conducted by the JST examined the mechanical state of the aircraft, the pilot's credentials, and the environmental conditions. Investigators found that the aircraft was maintained according to manufacturer standards and that the braking system was functional with no mechanical failures detected.
The pilot held a valid Private Pilot License and medical certificate. While the pilot had significant total flight time, experience specifically in this type of aircraft was limited to approximately 14 hours. Notably, the pilot had undergone a recent flight adaptation following a period of inactivity, but the investigation noted that the pilot's experience was more heavily weighted toward tricycle-gear aircraft rather than conventional gear models.
Weather conditions at the time of the accident were favorable, with light winds and high visibility, ruling out meteorological factors as a cause.
Findings
- The aircraft experienced an uncommanded longitudinal movement during the final stages of the landing roll.
- The pilot's limited experience with conventional landing gear aircraft may have been a contributing factor.
- The aircraft's design, featuring a conventional gear configuration and a sensitive braking system operated by the heels, makes it susceptible to instability during low-speed maneuvers.
- A forward center of gravity, potentially caused by the pilot occupying the front seat alone, may have increased the tendency for the tail to lift.