What happened
On June 17, 2018, a Piper PA-34-220T, registration PP-MEY, was operating a private flight from Coxim (SSCI) to the Córrego Azul Farm airstrip (SSZL) in Brasilândia, Mato Grosso do Sul. The flight, which included a pilot and two passengers, proceeded normally under visual flight rules (VFR) with favorable weather conditions.
Following a successful landing, the pilot attempted a 180-degree turn on the runway to taxi toward the parking area. During this maneuver, the right main landing gear encountered a hole in the grass runway caused by an anthill. The sudden sinkage caused the right gear strut to break, leading the propeller to strike the ground and resulting in structural damage to the right wing and fuselage. All three occupants escaped the incident without injury.
The investigation
The CENIPA investigation confirmed that the pilot was properly licensed and rated for multi-engine land operations, with a valid medical certificate. The aircraft's airworthiness documentation and maintenance logs were up to date. While the investigation noted that the aircraft's takeoff weight from the origin was approximately 54kg above the maximum allowable limit, the aircraft was within weight and balance limits at the time of the landing.
Investigators examined the runway surface at the Córrego Azul airstrip and identified several other anthills along the landing strip. These colonies had weakened the soil structure, reducing its load-bearing capacity below the official specifications. The investigation also noted that under Brazilian aeronautical law, the responsibility for maintaining private aerodromes in safe operating condition rests with the owner.
Findings
- The primary cause of the accident was the unstable runway surface caused by anthills that created localized points of soil failure.
- The right main landing gear was subjected to structural loads beyond its design limits when the gear sank into the hole.
- Inadequate maintenance of the aerodrome infrastructure allowed the presence of anthills to compromise the runway's integrity.