What happened
On October 25, 2003, at approximately 12:16 PM, an R-22 Beta II helicopter, registration PP-MIL, was conducting local flight training at Campo de Marte Airport (SBMT) in São Paulo. The flight involved an instructor and a student pilot performing simulated 180-degree autorotation exercises.
During the final phase of a simulated autorotation toward runway 30, the aircraft experienced a loss of control near the ground. The helicopter struck the runway with significant kinetic energy, tilting slightly to the left. The impact triggered a fire that caused the aircraft to slide approximately 40 meters along the pavement. While both occupants were rescued from the wreckage, the instructor succumbed to multiple traumas at the scene, and the student pilot was hospitalized with serious injuries.
The investigation
CENIPA's investigation focused on the execution of the autorotation maneuver and the operational environment. Investigators noted that the aircraft was within weight and CG limits and had undergone recent maintenance. However, the investigation highlighted discrepancies between the flight school's operating manual and the manufacturer's guidelines regarding autorotation procedures.
Technical analysis of the wreckage and witness accounts from other pilots indicated that the "flare" (the deceleration maneuver at the end of the autorotation) was performed with excessive intensity and an improper pitch attitude. This resulted in a high rate of descent and low rotor RPM at the moment of impact. The investigation also examined the ergonomic challenges of the R-22's dual-control configuration, where the cyclic position for the instructor is non-standard and potentially cumbersome during rapid maneuvers.
Findings
- The primary cause of the accident was inadequate judgment by the instructor, who failed to interrupt the maneuver once the aircraft reached a point of irreversibility.
- The student pilot's execution of the flare was excessive, failing to effectively reduce the aircraft's forward speed.
- The instructor's complacency allowed the training exercise to proceed into a critical state without timely intervention.
- The flight school's Standard Operating Procedures (SOP) were inconsistent with the manufacturer's safety notices and manuals.
- The ergonomic design of the R-22's shared cyclic control may have hindered the instructor's ability to execute precise corrective actions during dual-control flight.