Night Operations Chapter 12 Introduction Pilots rely more on vision than on any other sense to orient  themselves in flight. The following visual factors contribute  to flying performance: good depth perception for safe  landings, good visual acuity to identify terrain features and  obstacles in the flightpath, and good color vision. Although  vision is the most accurate and reliable sense, visual cues can  be misleading, contributing to incidents occurring within the  flight environment. Pilots should be aware of and know how  to compensate effectively for the following: For example, at night, the unaided eye has degraded visual  acuity. For more information on night operations, reference  Chapter 17, Aeromedical Factors, of the Pilot’s Handbook  of Aeronautical Knowledge (FAA-H-8083-25, as revised). •  Physical deficiency or self-imposed stress, such as  smoking, which limits night-vision capability  •  Visual cue deficiencies  •  Limitations in visual acuity, dark adaptation, and color  and depth perception 