What happened
On June 17, 2022, an AKB-18 experimental aircraft, registration PP-ZZK, was performing a private flight from Americana, SP, to the Clemente Verillo Aerodrome (SJEH) in Ribeirão Bonito, SP. The flight was operated by Clube de Voo Magnolia Cubs and carried a pilot and one passenger.
Upon landing at SJEH, the aircraft experienced a loss of control during the landing roll. The aircraft veered to the left side of the runway, approximately 430 meters from the threshold, and exited the paved surface. During the excursion, the aircraft struck ground obstacles, specifically lighting pylons mounted on concrete bases. The impact caused substantial damage to the aircraft, including broken main landing gear legs, damage to the right wingtip, fuselage dents, and propeller damage. Both occupants of the aircraft were uninjured.
The investigation
CENIPA's investigation confirmed that the pilot was properly licensed and medically certified, with sufficient flight experience for the operation. The aircraft, a single-engine amateur-built design, was in compliance with airworthiness requirements, including valid experimental certificates and up-to-date maintenance logs. Meteorological conditions at the time of the accident were favorable, with visibility and ceilings well above minimums.
The investigation focused on the landing technique and the airfield infrastructure. The pilot elected to perform a "wheel landing" (landing on the main gear first) without the use of flaps. This configuration resulted in a higher approach speed and a tendency to float during the flare, which increased the landing distance. Due to the nature of the wheel landing, the pilot avoided heavy braking to prevent a potential ground loop or capsize. Consequently, the aircraft traveled further down the runway than intended, leaving insufficient distance to decelerate before reaching the taxiway area.
Furthermore, the investigation examined the airfield's lighting pylons. It was determined that the lighting markers were not sufficiently frangible, in violation of RBAC 154 regulations, and that a drainage element was positioned above the ground level, creating an additional obstacle.
Findings
- The pilot performed a landing without flaps, leading to an increased approach speed and a floating effect during the flare.
- The landing roll distance was extended due to the limited use of brakes to avoid loss of directional control.
- Non-frangible airfield lighting pylons and elevated drainage structures acted as obstacles during the excursion.
- The pilot's piloting judgment regarding the landing configuration and braking contributed to the event.