HI.II.M.K9

From the FAA library

• Helicopter Flying Handbookp. 12-9
  Chapter 12: Night Operations › Night Flight › Illusions Leading to Landing Errors

  Outside visual references for airspeed and rate of closure may not be available, especially when landing in an unlit area, so pay special attention to the airspeed indicator. Although the landing light is a helpful aid when making night approaches ... atmospheric conditions encountered in night landing can create illusions of incorrect height above and distance from the runway threshold. Landing errors from these illusions can be prevented by anticipating them during approaches, conducting an aerial visual inspection of unfamiliar airports…

• Helicopter Flying Handbookp. 12-10
  Chapter 12: Night Operations › Helicopter Night VFR Operations

  helicopter night operations. Adding to that knowledge a study of visual illusions gives the pilot ways to overcome those illusions. Techniques for preflight, engine start-up, collision avoidance, and night approach and landings help teach the pilot safer ways…

• Pilot's Handbook of Aeronautical Knowledgep. 17-26
  Chapter 17: Aeromedical Factors › Vision in Flight › Autokinesis

  performed automatically. Figure 17-21. Geometric perspective. Night Vision Illusions There are many different types of visual illusions that commonly occur at night. Anticipating and maintaining awareness of them is usually the best way to avoid them. Autokinesis Autokinesis ... seconds. To prevent this illusion, focus the eyes on objects at varying distances and avoid fixating on one source of light. This illusion can be eliminated or reduced by visual scanning, by increasing the number of lights, or by varying…

• Aeronautical Information Manualp. 7-6-13
  Chapter 7. Safety of Flight › Section 6. Potential Flight Hazards › 7-6-14. Flying in Flat Light, Brown Out Conditions, and White Out Conditions

  This is particularly dangerous because the pilot needs those visual cues from their surroundings in order to make a safe landing. 4. Blowing sand and dust can cause an illusion of a tilted horizon. A pilot not using the flight ... incorrect control inputs which can quickly lead to disaster when hovering near the ground. In night landings, aircraft lighting can enhance the visual illusions by illuminating the brownout cloud…

• Pilot's Handbook of Aeronautical Knowledgep. 17-27
  Chapter 17: Aeromedical Factors › Flicker Vertigo › Night Landing Illusions

  Night Landing Illusions Landing illusions occur in many forms. Above featureless terrain at night, there is a natural tendency to fly a lowerthan-normal approach. Elements that cause any type of visual obscurities, such as rain, haze, or a dark ... Bright runway or approach lighting systems can create the illusion that the aircraft is closer to the runway, especially where few lights illuminate the surrounding terrain. Prior to flying at night, it is best to learn and know the challenges…

• Pilot's Handbook of Aeronautical Knowledgep. 17-9
  Chapter 17: Aeromedical Factors › Diving or Rolling Beyond the Vertical Plane › Coping with Spatial Disorientation

  Understand the causes of these illusions and remain constantly alert for them. Take the opportunity to experience spatial disorientation illusions in a device, such as a Barany chair, a Vertigon, or a Virtual Reality Spatial Disorientation Demonstrator. 2. Always obtain ... flight instruments. If intending to fly at night, maintain night-flight currency and proficiency. Include cross-country and local operations at various airfields. 5. Ensure that when outside visual references are used, they are reliable, fixed points on the Earth…