What happened
On June 3, 2003, an EMB-721 C, registration PT-EGL, departed Votuporanga, São Paulo, bound for Criciúma, Santa Catarina. The flight, which was intended to be a visual flight rules (VFR) operation, was carrying one pilot and five passengers. As the aircraft approached the municipality of Aurora, it encountered a powerful cold front characterized by thunderstorms, heavy winds, and low ceilings.
While navigating through these adverse conditions, the aircraft entered instrument meteorological conditions (IMC). During the flight, the left wing detached from the fuselage. This structural failure caused the aircraft to lose control, leading to a collision with the ground. The impact and subsequent fire resulted in the deaths of all 6 occupants.
The investigation
CENIPA investigators examined the wreckage and determined that the left wing separated from the fuselage due to excessive aerodynamic loads. Evidence from the propeller indicated that the engine shut down because the wing separation severed the fuel lines. The investigation also found that the right wing showed signs of upward bending due to overload, and parts of the horizontal and vertical stabilizers were lost or damaged following the impact of the detached wing against the fuselage.
Regarding the pilot, the investigation noted that while the pilot was experienced in the aircraft type, he did not hold an instrument rating (IFR). The investigation also explored the decision-making process, noting that the pilot had been under significant pressure from the passengers to complete the trip for a family funeral, which may have influenced his judgment regarding the deteriorating weather.
Findings
- Structural failure due to aerodynamic overload: The aircraft likely exceeded its structural limits (3.8 G) during an attempt to recover from an abnormal attitude or turbulence.
- Spatial disorientation: The pilot, lacking IFR certification, likely experienced spatial disorientation while flying in IMC, leading to abrupt control inputs.
- Adverse meteorological conditions: The presence of a cold front with thunderstorms and severe turbulence acted as a primary environmental trigger.
- Impaired decision-making: The pilot's decision to proceed despite known weather threats was influenced by psychological factors, including passenger pressure and a high degree of complacency.
Safety action
CENIPA issued several safety recommendations to address the human and operational factors identified:
- Integration of psychological factor studies into aviation seminars to improve crew decision-making.
- Emphasis on the necessity of thorough meteorological analysis for private operators.
- Increased awareness among private operators regarding the importance of observing the structural and operational limits of their aircraft.