What happened
On August 1, 2007, an AS350BA helicopter, registration PT-YCJ, was performing a survey mission for IBAMA in the state of Mato Grosso. After transporting technicians to Ponte Branca, the crew was returning to Barra do Garças. During the flight, the crew attempted to land in an open field to allow an aerial observer to attend to a physiological need.
During the approach, the aircraft lost control and struck the ground with a high rate of descent. The impact caused severe damage to the main rotor, transmission, tail cone, landing gear, and cabin, rendering the aircraft a total economic loss. While the pilot and the aerial observer escaped without injury, the co-pilot sustained serious spinal injuries.
The investigation
CENIPA's investigation examined several conflicting versions of the event. The crew stated the landing was a quick attempt to minimize time loss, which may have led to an inadequate assessment of the descent rate. An alternative version suggested the crew was conducting an improvised training maneuver involving a simulated hydraulic failure, which could have compromised flight control.
Investigators also examined the organizational structure of the operator's aerial operations unit (NOA). They found that the unit lacked formal integration into the agency's regimental structure and lacked a dedicated Flight Safety Program (PPAA). The investigation noted that the high turnover of personnel and the lack of standardized operational procedures contributed to an environment where improvised procedures could occur.
Findings
- Inadequate application of controls, which allowed the aircraft to impact the ground with a high rate of descent and a leftward tilt.
- Poor cockpit coordination between the crew members during the critical phase of the approach.
- Impaired judgment regarding the evaluation of approach height, vertical speed, and available power for corrections.
- Organizational deficiencies, including the absence of standardized training programs and a lack of formal operational doctrine for the mission types performed.
Safety action
CENIPA issued several recommendations to IBAMA, including the implementation of a formal Flight Safety Program and the establishment of a training program to ensure crews possess the necessary skills for their specific missions. Recommendations were also made to ANAC to review the applicability of specific aviation regulations based on the operational characteristics of the operator.