Robinson Helicopter R22 N337H accident near Charleston, South Carolina

Probable cause

The flight instructor’s abrupt evasive maneuver to avoid a reported unmanned aerial system, which resulted in a loss of forward airspeed and settling with power and a subsequent collision with trees and terrain.

NTSB analysis

During an instructional flight in the helicopter, the student pilot was on the controls. The flight instructor said the student had transitioned from a hover through effective transitional lift and established forward flight and then initiated a right turn. He added that, during the right turn, he and the student saw a small, white unmanned aerial system (UAS) about 10 ft in front of the helicopter at "eye level." The instructor took the flight controls and made a hard right and aft cyclic input. After the evasive maneuver, the helicopter had very little forward airspeed. The helicopter was about 40 ft above ground level as it began settling with power. The helicopter descended, and the tail rotor entered trees. The helicopter then developed a right spin, and the instructor rolled the throttle off to alleviate the spin and then increased the collective to try to cushion the landing. Subsequently, the helicopter impacted the ground and rolled over onto its right side.

A UAS was not recovered. It is likely that the instructor's abrupt maneuver led to the loss of forward airspeed and the helicopter's subsequent descent into trees, which resulted in the right spin from which the instructor could not recover before impact with terrain.

Text from the NTSB. Open the NTSB docket for GAA18LA131 for the full record.