What happened
On February 22, 2000, a Cessna A188B, registration PT-WVK, was engaged in agricultural spraying operations at Fazenda Mumbuca in Pejuçara, Rio Grande do Sul. The aircraft was carrying 360 kg of pesticides and nearly 100 liters of fuel, a configuration that reduced its maneuverability.
After completing a second spraying pass, the pilot executed a right-hand reversal turn, immediately followed by a level left-hand turn. During this sequence, the pilot lost visual contact with the spray markers and focused his attention on the spray pattern rather than the flight path. This loss of focus led to a collision with the treetops of several eucalyptus trees. The impact caused the pilot to lose control, resulting in a subsequent impact with the ground. The aircraft sustained severe structural damage and was declared a total loss.
The investigation
CENIPA's investigation examined the flight dynamics, the pilot's experience, and the operational planning. The investigation established that the pilot was fully qualified, with valid commercial and agricultural licenses, and possessed sufficient experience for the mission. The aircraft's maintenance records were up to date, and the weather conditions were favorable, characterized by sunny skies and temperatures around 34°C.
Investigators analyzed the aerodynamic state of the aircraft during the turns. They determined that the aircraft was operating at a low energy state. The high cockpit temperature and the repetitive, monotonous nature of the spraying task were also considered as factors that could have impacted the pilot's concentration.
Findings
- Excessive G-load: The pilot applied an excessive positive load factor during a tight turn to decrease the turning radius, which caused a significant loss of airspeed and kinetic energy.
- Loss of situational awareness: The pilot's attention was fixated on the alignment of the spray pattern (the work area) rather than maintaining monitoring of the flight path and altitude.
- Inadequate flight planning: The mission planning failed to account for the specific challenges of the terrain and the aircraft's heavy weight and reduced maneuverability during the turns.
- Pilot attitude: A combination of overconfidence and the pilot's tendency to fly at the minimum safety limits contributed to the decision-making errors during the maneuver.