Various complex motions and forces and certain visual scenes encountered in flight can create illusions of motion and position. Optical illusions optical illusions print version pdf read first. Collection of optical illusions phenomena of contrast gestalt laws geometricaloptical illusions new geometricaloptical illusions perspective, constancy of size subjective contours, foreground background. Thus, when learning to fly, or when transitioning into a new model, your goal should be to concentrate your flying hours in that model. Hazards associated with flying at night powerpoint. Other factors, such as co poisoning, smoking, alcohol, certain drugs, and a lack of oxygen also can greatly decrease night vision. Night operations online training course for the night waiver. Compared with day visual flight, there is more to night visual flight than meets the eye. The phrase night illusions refers to the tricks your eyes can play on you at night, which can cause confusion during night flights. Spatial disorientation from these illusions can be prevented only by visual reference to reliable, fixed points on the ground or to flight instruments. Height perception illusion flying over areas of very poor contrast e. The extra risks inherent in visual flight at night are from reduced visual cues, and the increased likelihood of perceptual illusions and consequent risk of spatial disorientation. Be aware, too, that it takes about 3045 minutes in dim light to maximize your night vision, so use special care at the beginning of flight and keep cockpit lighting low and consistent. Methodology of vfr night flying stanko mad magazine of.
The loss of important inflight clues greatly reduce a pilots ability to safely conduct operations at night. Illusion of a stationery point of light that appears to be moving eg. Chapter 10 night operations federal aviation administration. Factors relating to night vision lighting eye physiology see private pilot textbook 103 define all areas of the eye. Low visibility andor precipitations are a circumstantial factor in more than 70 % of. The following discussion covers some of the common situations that cause illusions associated with night flying. Here is an easy mnemonic to remember the 11 night visual illusions is. Visual illusions affect the flight crews situational awareness. Trescott tips max trescott, master certificated flight instructor cfi. Oct 02, 2009 this video demonstrates a broad number of illusions a pilot might experience during their career.
Then the first letter of each word prompts each of the 11 night visual illusions. Dark nights tend to eliminate reference to a visual horizon. Elaborating on gibsons insights article pdf available in new ideas in psychology 36. Illusions cont false horizons cloud formations andor uneven ground give the illusion that the ac has drifted or is at an unusual attitude. Landing visual illusions, autokinetic illusion, oculogravic and oculogyral illusions, empty field. Figures 1, 2, and 3 also show the illusions that changes in runway width and slope can generate during a night visual approach.
These are a group of three various illusions caused by linear accelerations. While flying below controlled air space in san diego, california, u. Hazards associated with flying at night presented by name transport canada, system safety. Understanding of particularities of night flight and corresponding procedures, including night vision difficulties, use of lighting, navigation and airport work at night. Understanding physiological conditions which may degrade night vision. Srm and adm training focus on the decisionmaking process and on the factors that affect a pilots ability to make effective choices. Risk was increased by a factor of 2 when night flying and by a factor of about 3 if flying in cloud or in degraded visual conditions. Abstract continue on reverse if necessary and identify by block number to investigate the breadth of visual illusions experienced by aviators flying with. This can commonly happen at night, or when flying over banks of cloud or water.
Failure of communication within the cockpit led to an almost fourfold increase in risk. Night illusions in addition to night vision limitations, night illusions can cause confusion and distractions during night flying. Night vision goggles nvg helicopter training program. The same dive or climb illusion can happen by a change in aircraft pitch occurs while flying toward a light. Airplane flying handbook federal aviation administration. Illusions rank among the most common factors cited as contributing to fatal accidents.
To put anxiety at ease, berkshire aviation enterprises certificated flight instructor and ground instructor jason archer shares a few tips that have worked for his students at walter j. More about night flying can be found here night flyingpart 1rules and here night flyingpart 2airmanship more about the eye can be found here human physiology more about fatigue can be found here pilot fatigue more about visual illusions can be found here inflight visual illusions more about colour blindness can be found here colour blindness. Low visibility andor precipitations are a circumstantial factor in more than 70 % of approachandlanding accidents, including those involving cfit. Flight crew members who are taking a drug which has a systemic effect will be restricted from flying duties until. Nov 24, 2016 autokinetic illusion occurs when small eye movements in poor visual conditions, such as during night flying, are interpreted by the brain incorrectly, giving the impression of movement of the object being viewed. Night illusions in addition to night vision limitations, pilots should be aware that night illusions could cause confusion and concerns during night flying. Cloud layers or even the northern lights can confuse a pilot and indicate a. Each step in the process of a night flight requires special knowledge and close attention to detail.
Collection of optical illusions phenomena of contrast gestalt laws geometricaloptical illusions new geometricaloptical illusions perspective, constancy of size subjective contours, foreground background perceptual conflicts impossible figures and more. Autokinetic illusion occurs when small eye movements in poor visual conditions, such as during night flying, are interpreted by the brain incorrectly, giving the impression of movement of the object being viewed. Appropriate medical restrictions from flying will be made under the following conditions. You may also experience certain visual illusions when flying at night. Prior to conducting waivered operations, the responsible person listed on the waiver must ensure the remote pic and vo are trained to recognize and overcome visual illusions caused by darkness, and understand physiological. At night, banking into or away from a line of lights will give the illusion that a dive or a climb is occurring. These dangers can, however, be managed effectively. Traditional pilot training emphasizes flying skills, knowledge of the aircraft, and familiarity with regulations. During experiments conducted on the hu man centrifuge8 another type of visual illu sion was discovered. A pilot may confuse the lights on the ground as a constellation of stars. Several factors were identified that increased the relative risk of a disorientationrelated accident. Night vfr presents risks not typically associated with flying during day vfr.
Sep 04, 2017 be aware, too, that it takes about 3045 minutes in dim light to maximize your night vision, so use special care at the beginning of flight and keep cockpit lighting low and consistent. The 11 night visual illusions ems flight safety network. False visual reference illusions may cause the pilot to orient the aircraft in relation to a false horizon. He suggests waiting until you reach 100 hours of experience in one particular model before attempting a dual rating with another model. False visual reference this happens when a pilot uses a false visual reference to orientate the. Faa required night vision training dji inspire drone forum. And the potential for unwittingly flying from visual to instrument meteorological conditions imc is at its greatest. Night vision goggles, also known as nvgs, are helmetmounted devices which amplify available light. Flying at night is no different than flying in the day. In addition to night vision limitations, night illusions can cause confusion and distractions during night flying. An object viewed directly at night might not be seen due to the night blind spot. Comprehension of night flight, including vision and illusions, lighting, and operations procedures, prior to conducting an initial night flight.
Visual approach at night during a visual approach at night, fewer visual references are usable, and visual illusions and spatial disorientation occur more frequently. A 10 degree bank with only the approach lights visible can cause an illusion that the lights are sloping from above. Learning night flying techniques brings up special challenges for students who are more familiar with daytime operations. Pilots need to rely less on outside references and more on flight and navigation instruments at night. Your best defense, the best strategy, is to combine skill and judgment with an indepth knowledge of night flying. Even though most of the hazards associated with flying at night have been known in the aviation industry for many years, these types of accidents continue to occur, which would indicate that pilots knowledge or awareness of these hazards is still very low. Night waiver recommendations dji mavic drone forum. Jan 03, 20 several factors were identified that increased the relative risk of a disorientationrelated accident.
Night flying is risky and more dangerous, comparing with flying during daylight, so it is essential to seek training with a flight instructor specifically for night flying. There was no systematic variation from visual illusions in night flying trial to trial, or day to day, in the judgments of either apparent motion, or apparent dis placement, to indicate that the subjects were becoming habituated to rotation. Deficiencies in vitamins a and c have been shown to reduce night acuity. Visual approaches at night present a greater exposure because of reduced visual cues, increased likelihood of visual illusions and risk of spatial disorientation. Make sure to address how you will deal with night illusions, including remedies such as flying for shorter periods of time, using a window of time to allow your eyes to adjust after turning the lights on your. Koladza airport in great barrington, massachusetts. Spatial disorientation from these illusions can be prevented only by visual. Reduction alar task force found that visual approaches were being conducted in 28 percent of the 76 approachandlanding accidents alas and serious incidents worldwide in 1984 through 1997. Eastern air lines flight 401, lockheed l1011, dec 1972 american airlines flight 965, b757, dec 1995 2. Spatial disorientation federal aviation administration.
Do you need to fly under a part 107 night waiver or a public coa which says that you need training on. Oct 19, 2017 the phrase night illusions refers to the tricks your eyes can play on you at night, which can cause confusion during night flights. Airplane flying handbook, faah80833b full version low resolution pdf, 89. There are many different types of visual illusions that commonly occur at night. Royal flying doctor service from derby to pick up a patient at kalumburu mission in the kimberleys. The blind spot occurs when the fovea becomes inactive in low light conditions and involves an area from 510 degrees wide in the center of the visual field. False visual reference this happens when a pilot uses a false visual reference to orientate the aircraft, because of the confusing ground and star light. Methodology of vfr night flying stanko mad magazine. Night flying part 3 human factors aviationknowledge.