What happened
On May 7, 2018, an agricultural spraying operation involving a Neiva EMB-201A, registration PT-UCP, resulted in a significant accident near Chapadão do Céu, Goiás. The aircraft was performing routine pesticide application over a cornfield, operating from a private landing strip at Fazenda RS.
After approximately ninety minutes of flight, the pilot attempted a maneuver intended to position the aircraft for landing. During this sequence, the aircraft entered a circular climb resembling a loop, at one point appearing upside down to a ground observer. The aircraft subsequently lost control and struck the ground at a steep angle, impacting with the left wing and landing gear before the nose dug into the soil. The impact caused substantial damage to the airframe, including the separation of both wings and the propeller assembly. The pilot sustained serious injuries.
The investigation
CENIPA investigators examined the wreckage and analyzed flight data from a Differential GPS (DGPS) installed on the aircraft. The investigation confirmed that the aircraft was airworthy, properly weighted, and maintained according to regulations. Mechanical failure was ruled out, as both the ground crew and the wreckage analysis showed no evidence of engine or system malfunction.
Data from the DGPS revealed that while the aircraft typically operated at low altitudes (around 20 feet) and high speeds (120 MPH), it had been performing turns with high bank angles between 45° and 60°. Crucially, the investigation found that the stall warning system had been intentionally deactivated by the pilot, as the circuit breaker for the stall detector had been pulled. The pilot had previously stated that the warning system was more of a hindrance than a help during flight.
Findings
- The pilot executed a maneuver outside the aircraft's certified flight envelope, specifically an unauthorized acrobatic maneuver.
- The pilot's improper use of flight controls led to a loss of control, likely preceded by an aerodynamic stall.
- The deactivation of the stall warning system prevented the pilot from recognizing the onset of the stall condition.
- Inadequate pilot judgment regarding the aircraft's performance limits contributed to the accident.
- A lack of effective managerial supervision allowed for the persistence of unsafe operational habits, such as high-bank turns and the disabling of safety equipment.