What happened
On 1 December 2022, a Robinson R66 helicopter, registration PK-VPJ, was conducting a tourism flight near Ungasan, Bali. After completing two successful sightseeing legs, the pilot began a third flight carrying three passengers. To ensure the flight met the standard 12-minute tour duration, the pilot extended the route toward Pandawa Beach and reduced airspeed to approximately 50 knots.
During the return approach to the Fly Bali Heliport, the pilot noted a 10-knot northwest wind. As the aircraft descended to an altitude of roughly 30 feet, it began to yaw to the right. Attempting to execute a go-around, the pilot increased the collective slightly, but the rightward yaw intensified, leading to an uncontrolled nose-down attitude. The pilot managed to recover the aircraft's level attitude just before impact, causing the helicopter skids to strike a grassy area approximately 30 meters short of the intended landing point. There were no injuries to the passengers or crew, though the aircraft sustained minor damage to the aft cross tube skid.
The investigation
The KNKT examined the flight history, aircraft maintenance records, and the pilot's operational procedures. The investigation confirmed that the aircraft was airworthy and the pilot held valid certifications. Investigators reviewed the company's Operation Manual, which outlines specific procedures for handling a loss of tail rotor thrust. Additionally, the investigation looked into manufacturer safety notices regarding unanticipated yaw phenomena.
Findings
- The pilot's decision to perform a go-around involved pulling the collective, which coincided with a progressive rightward yaw.
- The recovery actions taken by the pilot during the incident deviated from the company's established procedures for loss of tail rotor thrust, which mandate closing the throttle and entering autorotation.
- The pilot had not been briefed on the manufacturer's Safety Notice SN-42, which addresses unanticipated yaw caused by wind conditions or improper pedal inputs.
- The aircraft's aft cross tube skid experienced deformation beyond its structural limits during the touchdown.
Safety action
At the time of the preliminary report, the KNKT had not been notified of any safety actions taken by the operator. The agency has issued recommendations for the operator to review pilot training regarding problem recognition and recovery procedures, as well as to ensure all manufacturer safety notices are properly distributed and briefed to flight crews.