What happened
On October 21, 2022, a Robinson R22 Beta helicopter, registration CC-PHQ, was conducting a flight instruction session near the Huechún Reservoir in the Colina commune, Metropolitan Region. The flight, which originated from Chicureo Aerodrome, was part of a private helicopter pilot training program.
During the flight, the crew was practicing a simulated emergency maneuver known as a direct autorotation. As the student pilot executed the maneuver, the aircraft's flight parameters deviated from the required safety margins. This resulted in an uncontrolled descent that led to the helicopter striking the ground and overturning onto its left side. Despite the impact, both the flight instructor and the student pilot evacuated the aircraft on their own and were uninjured.
The investigation
DGAC Chile examined the technical and operational aspects of the occurrence. The investigation confirmed that the aircraft's maintenance records were up to date, with the last 100-hour/annual inspection completed shortly before the event. No mechanical failures or technical discrepancies were found in the engine, rotor systems, or fuel supply.
The investigation also reviewed the crew's qualifications, finding that both the instructor and the student held valid licenses and medical certificates. Meteorological conditions at the time of the accident were reported as CAVOK (ceiling and visibility OK), providing suitable conditions for flight operations.
Findings
- The student pilot failed to maintain proper control of flight parameters during the simulated autorotation, specifically allowing the airspeed to drop to between 4/5 knots, while RPMs approached the upper limit and the descent rate increased to between 1,500 and 1,800 feet per minute.
- The flight instructor provided delayed supervision and failed to intervene in time to correct the deviating parameters.
- The instructor did not execute a missed approach or aborted maneuver procedure (procedimiento de frustrada) before reaching 40 feet above ground level (AGL) to restart the practice safely.