HELICOPTER FLIGHT IN DEGRADED VISUAL CONDITIONS

摘要

The UK Civil Aviation Authority has sponsored research to investigate the causes of accidents involving civil helicopter operations in degraded visual cueing conditions. The objective of this initiative was to identify potential developments of the civil regulations and requirements that would help to prevent and/or mitigate accident-prone scenarios. The research involved a review of accident statistics and a follow-on piloted simulation investigation, the results of which were compared with the findings of a review of the applicable civil regulations. Poor aircrew situational awareness and spatial disorientation, or controlled flight into terrain following inadvertent entry into Instrument Meteorological Conditions, were identified as primary causal factors. The strong inter-dependency between helicopter handling qualities and the visual cueing environment was highlighted, emphasising the need for improved instrument displays for flight in degraded visual conditions, and improved requirements and guidance for control augmentation and flight control mechanical characteristics.