Editing Spatial disorientation (section)

== Visual illusions ==
Even with good visibility, misleading visual inputs such as sloping cloud decks, unfamiliar runway grades, or false horizons can also form [[optical illusion]]s, resulting in the pilot misjudging the vertical orientation, aircraft speed or altitude, and/or distance and [[depth perception]]; these could even combine with nonvisual illusions from the vestibular and proprioceptive systems to produce an even more powerful illusion.<ref name=FAA-spatial-vis>{{cite web |url=https://www.faa.gov/pilots/safety/pilotsafetybrochures/media/SpatialD_VisIllus.pdf |title=Medical Facts for Pilots: Spatial Disorientation, Visual Illusions; safety brochure AM-400-00/1 |author=Antuñano, Melchor J. |access-date=9 February 2021 |publisher=Federal Aviation Administration}}</ref>