Accident Description
On 10 October 2021 at 15:25 local time, a Robinson R-44 Raven I (registration ES-ARM) was taking off from the Paljassaare landing site. During the takeoff, the helicopter began to rotate left on the ground. The skids lost contact with the ground, and the helicopter tilted to the right side. The main rotor blades struck the ground, broke, and the engine stopped. The aircraft sustained severe damage. The pilot was not injured and exited the helicopter unaided.
Aircraft and Pilot Information
The aircraft was a Robinson R-44 Raven I, a four-seat single-engine helicopter, manufactured in 2021. The pilot held a valid PPL(H) license and a Class 2 medical certificate. Total flight experience was 281 hours, of which 273 hours were on the R-44, with 13 hours in the last 90 days.
Flight Sequence
According to the investigation, the pilot began startup procedures at approximately 15:22 to fly to Tallinn Airport for refueling. At 15:25, after completing pre-flight procedures, the pilot began the takeoff. As rotor rpm increased, the helicopter's nose turned slightly left. At that moment, the pilot's attention was directed to a portable navigation device on the left seat, and he attempted to adjust it with his left hand. The pilot pressed the left pedal, causing the helicopter to rotate left on the ground. He then moved the cyclic right. When the helicopter had rotated about 180 degrees, he pulled the collective up, causing the skids to lift off the ground. The helicopter tilted right, and the main rotor blades struck the ground. The aircraft completed approximately a 490-degree rotation. The rotor blades broke, the engine stopped, and the helicopter settled on its right side.
Investigation Findings
An examination of the helicopter's structure found that all damage resulted from ground impact during the accident, and no technical malfunctions or failures were identified. The Estonian Safety Investigation Bureau (OJK) concluded that the accident was caused by pilot error: distraction during a critical phase of flight. The pilot did not have a detailed memory of the exact circumstances after the accident.
Probable Cause
Pilot error – distraction during the critical takeoff phase.