Illusions in flight, which can become a tragic reality
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Illusions in flight, which can become a tragic reality

Illusions in flight, which can become a tragic reality



We will talk not about the magic tricks that you can show the passenger-a magician, or a pilot with cabin crew. We will talk about very serious things: on the illusions that can occur when the pilot flying the aircraft instrument.

As everyone knows, there are two options for piloting the Sun:

  • Piloting on visual flight rules VFR (Visual flight rules, VFR). With this flight, the pilot maintains direct visual contact with the ground reference points, or at least see the horizon.

  • Piloting on flight rules IFR instrument (Instrument flight rules, IFR)

That's about the psycho-physiological peculiarities of piloting instrument and would like to talk separately.

There are many reasons why you have to fly IFR. It can be fog, cloudy, nighttime, etc. Of course, the pilot must have special training for instrument piloting, appropriate clearance with an entry in the flight book. But, despite the training, and even probably a lot of experience flying under IFR, no pilot is immune to falling into the trap of spatial disorientation. According to statistics (oh, this notorious statistics!), About 15% of aviation accidents occur due to visual illusionsAppearing in the pilot. And about 90% of these accidents end fatally.

We decide what is called illusion:

Phenomena incorrect, inaccurate reflection of objective properties of things. These inaccuracies and distortions can be caused by physical, physiological and psychological reasons.

Platonov KK "Essays on the psychology of the pilots' 1948g.


To help explain who the Platonov KK

Konstantin Platonov prominent Soviet psychologist, doctor of psychology and medical sciences, professor, colonel of medical service. Author of publications in psychology 300 issues that have been translated into the language of 21 the world. His work in psychology, and in particular for aviation psychology have not lost their relevance in our time. Earlier, in Soviet times, it works on aviation psychology studied in schools of the Air Force and Civil Air Fleet.

He was very serious, studied psychology pilots and other aviation professionals for many years. He has written books such as:

  • Essay on psychology for pilots. 1948 of

  • Man in flight. 1957 of

  • Flight Work Psychology. 1960 of

  • Aviation psychology. 1963 of

Particular attention is paid Konstantin Platonov illusions that arise in the so-called "blind" flight, ie flight instrument.

Here is what he wrote in 1960 year: "Illusions in flight instrument may occur in the vast majority of pilots, although at different rates, in different forms, severity and persistence ... The shape of the illusion are very diverse, but more often marked illusion rolls, spins, dives and pitching . Illusion roll can reach 75 ° and move in the illusion of the inverted flight ... "(Platonov KK "Summer Work Psychology"; Voenizdat 1960)

The main cause of the illusions in a blind flight, it malfunctions our vestibular apparatus. I can not exactly fail, and errors of perception. All of course know that such a body exists in us, but very few people is, how it works and what it consists of. Without going too much into the physiology, we try to understand how the spatial orientation of a person.

So: the vestibular apparatus (BA) is the organ that perceives the position of the head and body in space and the direction of movement of the body in vertebrates and in humans. VA is part of the inner ear. The basis of the VA is the semicircular canals and the vestibule. That's it they are responsible for spatial orientation. Semicircular canals are located in three mutually perpendicular planes. Inside these channels there are sensitive hairs, and the channels themselves are filled with a gelatinous liquid. With any, even the slightest movement of the head, the fluid in the channels is displaced, presses on the hairs, and they in turn generate impulses in the endings of the vestibular nerve. The brain immediately receives information about changes in the position of the body. Thus, the scheme of the VA operation looks simplistic. In addition to the work of IA, the definition of spatial position is also determined by external organs, primarily vision.


Motion sickness and motion sickness

When the brain receives information from the view of the change, for example, the horizon line, the signal goes to the VA, which has its own information about the situation. There is a conflict, "failure" in the processing of signals, and the person becomes ill. This is the "motion sickness", aka "air sickness" motion sickness.

Even the first pilots noticed that gymnastic exercises help from motion sickness, especially those associated with a rapid change in body position in space. Then doctors and scientists came to grips with this issue. The first simulators for strengthening VA and its training appeared. Even in simple flying clubs of the USSR DOSAAF, in addition to simulators for practicing landing on a parachute, there were swings, carousels, and lopings. It was on these shells that VA, pilots, and then cosmonauts were trained. In trained people, the vestibular apparatus becomes less sensitive to shaking and overload, it adapts more quickly to a constantly changing environment. That is, in the chain of the eye - the brain - the vestibular apparatus, the latter ceases to react so sharply, since it is already accustomed to changes.


That hide the pilots

As soon as instrument flights began to take up more and more space in both military and civil aviation, the question of air illusions became quite acute. But the question is: how to investigate this phenomenon? Who of the pilots will voluntarily tell someone, and even more so a doctor, how he made a mistake in space, stopped trusting instruments and miscalculated? Devices that can fix a false idea of ​​a pilot about his position in space have not yet been invented. And those who could tell about their mistake, who could not find a way out of a difficult situation, could no longer say anything.

With a small degree of confidence, it can be understood that the pilot lost spatial orientation, by means of objective control (SOC), on-board recorders. And then, just for a chaotic situation or inadequate sun behavior in flight. And such an assessment, it will be only approximate.

Illusions in flight, which can become tragic realnostyu1


The benefits of combining professions

In 1992, the aviation physician and an experienced pilot Gillingham, Kent, Described and classified the main types of disorders of spatial orientation (NGOs). He described this syndrome as a "False sense of pilot its spatial position and movement relative to the plane of the earth's surface." This definition covers all cases of distorted and false perception of the spatial position of the pilot of his plane at the corners of the pitch, roll and altitude.

So: for Gillingham NGOs are classified into three main types:

  • A type I.

It covers unconscious or unidentified violations. And if you say simply, this is a situation in which the pilot is not able to feel that flying is not there. According to statistics, accounting for up to 50% of all aircraft accidents associated with spatial illusions.

  • A type II

This deliberate violations. Conflict between instrument readings and pilot sensations. Most often occurs with pilots who have recently completed flight training and do not yet have experience flying with instruments and / or limited visibility. Once in such a situation, the pilot of the plane thinks that “the instruments are broken”, because his own vestibular apparatus says differently, and relies on his erroneous sensations instead of working instruments.

  • A type III

Violation of spatial orientation with a complete loss of pilot's performance. Physiological symptoms accompanying disorientation (overload, muscle spasms, visual defects, nausea, dizziness, etc.), which deprive the pilot of the ability to independently fly the aircraft. 


In violation of the first type (NRDI) the pilot is convinced by his feelings that the aircraft he is piloting is in a stable spatial position, on a stable flight path. At the same time, the indications of the main flight and navigation instruments about dangerous deviations of the aircraft from the normal flight regime may go unnoticed due to the overload of the pilot or the diversion of attention from the piloting tasks to other tasks, due to absent-mindedness or simply deliberate ignorance of instrumental information about the flight. More than 50% of all air crashes are subsequently designated as "Manned flight technically serviceable aircraft before the collision with the ground."

The illusion of heel is possible when performing a wide established slow turn with roll. During the turn, the fluid in the semicircular canals takes a settled position, the hairs in the channels cease sending a signal to the brain. The position of the body begins to be perceived as normal. When the roll is sharply leveled, the vestibular apparatus receives a signal about the change in the "normal" position of the body (although the VS is aligned), that is, according to the sensations, the pilot seems to have the opposite roll. If the pilot trusts his feelings, and ignores the instrument readings, he will insert the aircraft into a roll.

  • NGO-II Describes the state of the sensory conflict between the readings of the instruments and their own subjective perception of the spatial position. In this violation the pilot is inclined to trust more to his sensations than to the readings of the instruments. This is typical for inexperienced pilots in instrumental flight. The situation is perceived as a failure of devices. Cases of NGO-II are more common for flights in AON, in small aircraft. It is clear that the failure of all flight-navigation instruments on modern "large" military and civil aircraft is unlikely, in contrast to less equipped with duplicated small aircraft.


Illusions in flight, which can become tragic realnostyu3


  • NGO-III It covers those violations NGOs spatial orientation when the pilot is aware of this state, but is not able to get out of it. This may occur as a result of complete disorganization of the work of visual, vestibular and motor analyzers in flight. Or the inability to perform purposeful motor actions.


In general, Type II and Type III violations are considered less likely events, but they continue to appear in aviation medical statistics of flight accidents. And according to some reports, Type III accidents in fighter aircraft account for 10-15% of all cases.

The most common forms and varieties of visual illusion of pilots are those associated with the perception of the ground and the horizon. Examples of such distortions are illusions, when the pilot takes the slope of the upper edge of an approaching solid cloud front, the slope of the auroral lines as the horizon line. Examples of skewed horizon perceptions include piloting at night over a coastline when its lights are perceived as the horizon. And the pilot decides to change the pitch angle. A false perception of the horizon can arise when piloting in mountainous conditions, when the slope of one of the walls of a gorge of a large area and length is perceived as a natural horizon line.

Known illusions occur when you change the familiar space of visible illumination. For example, when flying above the water surface in the light conditions of low sun water surface, in contrast to the dark sky covered with clouds solid. change the "top" of the concept in some places and "bottom" in such cases. Such NGOs are described in many books, the memoirs of the famous pilots. There have been cases when the reflective night sky with stars in the mirror of water, in clear weather, so distorted the reality that the pilot made the decision to turn over "upside down."

Night lighting area may lead to the fact that the pilot receives ground lights for the light of stars and also loses orientation.

And this is only the most common disorders of spatial orientation.

To summarize, this brief excursion into the physiology and psychology of disorders of spatial orientation, we can say one thing: trust instrument. And to them unconditionally trust

  • they should always be in perfect order.

  • they must pass all inspections and maintenance work.

  • You must know them very well and know how to use them all together and each separately.

When piloting under IFR, no secondary devices. There are basic, and there is a duplicate, but all of them together and give a complete picture of the spatial location of your aircraft.


Review prepared by Valery Smirnov

Photo by the author

I have a large number of helicopter raids at night, like all pilots in the Arctic. Yes, such a feeling of "incorrectness in instrument readings" in IFR flights does not occur rarely among pilots. We did not hide it and fought this false sensation very simply: it is worth distracting from the instruments for literally a second and shifting our attention, for example, turning towards the door, or better to open it and look inside the cargo compartment. Everything, shifting your attention back to the devices, you see that the devices are showing correctly and there is no roll!

Thanks to Vitaly. On such a simple method of leaving the disorientation ..

Hello, and what to do if the devices otkozali or erroneously show indicators As this pilot can cope with that if the indicators show the first wrong and then correct ie if enabled stabilization mode ...


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