ERA17LA332 · Robinson Helicopter R22 Beta

A private pilot in a fixed-wing airplane was landing at the airport following a personal flight, and a flight instructor and a pilot receiving instruction were conducting a flight review in a helicopter and practicing maneuvers in the airport traffic pattern. The instructor reported that he or the pilot receiving instruction made radio calls on the common traffic advisory frequency (CTAF) before each turn in the pattern. When the helicopter was 1 mile from the runway, the pilot receiving instruction turned the helicopter onto final approach. After completing a steep approach, the pilot receiving instruction brought the helicopter into a hover about 15 ft above the runway threshold. The airplane pilot stated that he heard a heavy buzzing sound on the CTAF, like a helicopter rotor, and a barely distinguishable word; he scanned for traffic and declared being on downwind. The airplane pilot quickly turned to the base leg of the traffic pattern and then proceeded to land; the airplane then struck the helicopter from behind as the airplane landed on the same runway as the helicopter. The pilots of both aircraft reported scanning for traffic; however, the airplane pilot reported that he did not see the helicopter until about 2 seconds before the collision, while the flight instructor and pilot receiving instruction in the helicopter did not see the airplane before the collision, as the helicopter was oriented down the runway with its tail pointed toward the runway's approach end. Given that the airplane struck the helicopter from behind while landing, it is unlikely that the helicopter pilots were in a position to see and take action to avoid the airplane. Conversely, because of the airplane's position, the airplane pilot had the best opportunity to see and take action to avoid the helicopter.

Postaccident examinations of the radio communication systems in the airplane and helicopter did not reveal any anomalies. The instructor in the helicopter indicated that radio calls were made during every turn while the helicopter was in the airport traffic pattern. The airplane pilot indicated that he was operating on the CTAF and that he was confident his calls on the radio were heard. However, the pilot of another airplane who was about 2 miles west of the airport and was monitoring the airport's CTAF recalled hearing a radio call from the helicopter announcing that it was on a 1-mile final approach to the runway at 500 ft but did not recall hearing any transmissions from the airplane. Thus, given that the airplane pilot's transmissions were not heard, it is likely that he did not adequately transmit the airplane's position while in the airport traffic pattern.

Verbatim NTSB analysis and probable cause from the NTSB dataset