What happened
On 28 May 2021, a Robinson R44 Raven II helicopter, registration PK-RTO, was conducting circuit flight training at Wiladatika Airport in Jakarta. The flight, operated by Genesa Flight Academy, was intended to provide a student pilot with experience in specific emergency maneuvers.
During the third circuit of the flight, the instructor took control of the aircraft to demonstrate an autorotation over water. After descending to approximately 700 feet, the instructor reduced the throttle to simulate a power failure and selected a nearby shallow lake as the landing spot. As the aircraft reached about 50 feet above the water, the instructor attempted to execute a go-around by gradually increasing the throttle. However, the main rotor RPM failed to increase, leaving the crew with no choice but to commit to a water landing.
The helicopter struck the water and subsequently submerged in the shallow lake. The instructor and student pilot managed to unbuckle their seatbelaries and evacuate the cabin by breaking the windshield. Both occupants were able to swim to safety, and no injuries were reported, though the aircraft sustained substantial damage.
The investigation
The KNKT investigation examined the flight path using GPS data and reviewed the training protocols of the flight academy. Investigators noted that the aircraft was not equipped with emergency flotation devices or a flight recorder. The investigation also reviewed the qualifications of the crew, noting that while both held valid licenses, this specific water-based autorotation exercise was a first-time maneuver for both the instructor and the student.
Findings
- The primary cause of the ditching was the failure of the main rotor RPM to recover during the attempted go-around at low altitude.
- The flight academy's existing instructor guidance lacked specific procedures or safety protocols for conducting autorotation training over water.
- The aircraft lacked necessary emergency equipment, such as flotation gear, for water-based maneuvers.
- The exercise was being performed for the first time by both the instructor and the student pilot.