Leans and Pitch-Up Illusions Affect Aviation Safety

4 Aviation Biology Student's Name: Student's ID: Subject: Introduction 2 Description of leans and pitch-up illusions 2 Leans and pitch-up illusions affect aviation safety 2 Conclusion 4 References 5 Introduction The paper aims to demonstrate an understanding of how lean and pitch-up illusions affects aviation safety. Description of leans and pitch-up illusions The leans are considered to be the common type of vestibular illusion that results in spatial disorientation which determines a false sensation of roll attitude.

Aviation Biology
Student's Name:
Student's ID:
Subject:

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Table of Contents
Introduction......................................................................................................................................2
Description of leans and pitch-up illusions.....................................................................................2
Leans and pitch-up illusions affect aviation safety..........................................................................2
Conclusion.......................................................................................................................................4
References........................................................................................................................................5

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Introduction
The paper aims to demonstrate an understanding of how lean and pitch-up illusions affects
aviation safety. Lean and pitch-up illusions are determined to be the vestibular system.
Vestibular systems are responsible for the sense of balance in humans that possess semicircular
canals. In aviation, illusions occurs when the brain is unable to recognize the inputs from a visual
system and vestibular system. Thus, the paper will describe the impact of lean and pitch-up
illusions in aviation safety.
Description of leans and pitch-up illusions
The leans are considered to be the common type of vestibular illusion that results in spatial
disorientation which determines a false sensation of roll attitude. Different situations may result
in leans, but the most common is the retrieval from a corresponding turn to level flight at the
time of flying through instruments (Stanko, Sabo, Sekelová & Rozenberg, 2017). The lean
illusion may take place when the movement of the flight is below the sensory threshold for the
semicircular canal during slow rotational movement.
Pitch-up illusions are also known as somatogravic effect that are caused due to the changes in
gravity forces or changes in linear decelerations and acceleration. These involve the head-down
illusion, head-up illusion as well as inversion illusion (Stróżak et al., 2018). Such illusions are
amplified at the time when the visual cues are absent and are confused with a climb.
Leans and pitch-up illusions affect aviation safety
At the time of lean illusion, if a pilot fails to observe the disorientation and continues to lean, the
flight may over the bank in the opposite track and causes rolling. This is regarded as the common
type of disorientation faced by pilots. If spatial disorientation is incorrect, it may result in
controlled flight into terrain and loss of control (Lewkowicz, Stróżak, Bałaj & Francuz, 2019).
At the time of stepping into a turn, the vestibular system will carry the turning movement and
initial rolling. When a flight is stabilized in an angle of bank and a steady rate-of-turn, the
vestibular system will catch up with the aircraft, thus the pilot will sense that the aircraft is at
appropriate level and straight. In this condition, the pilot can adjust the aircraft and his body

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towards a new neutral position. Due to the occurrence of leans illusion, the pilot is unable to
identify a turn and depending upon the power management, the speed of the flight will increase.
Due to leans illusions, the canals are unable to identify the rotational acceleration, which is near
about 2 degrees per second or even lower than this. Moreover, because of the immediate return
to wings-level flight, the pilot becomes unaware of such changes in the attitude (Priot, Vacher,
Vienne, Neveu & Roumes, 2018). In cases of spatial disorientation, the pilots must be able to
depend upon their flight instruments while making control inputs for overrising false sensations.
As a result, a pilot is unable to interpret the correct attitude of the aircraft or airspeed associated
with another point of reference or to the earth. Therefore, to overcome with such adverse effects
of lean illusion, the pilot and the aircrew members must be provided with aviation medicine
training that will help in understanding the vestibular system (Ilbasmis & Yildiz, 2017).
On the other hand, if a pilot experiences a pitch-up illusion, he believes that they are at a much
greater distance than they are and feels that the aircraft may stop (Bałaj et al., 2019). Hence,
when pilots believe that they are minimizing pitch to a normal level, at that time, the aircraft may
be in a nose-down or level attitude. By the time the pilot realize what has happened at the low
attitude, it might be too late to pull through. However, pitch-up illusion results in an immediate
increase in the thrust from the engines that creates a reassuring sensation for the pilot that the
flight is climbing when it is not. An irrelevant pitch-up response by the pilot is less dangerous
but may result in a huge loss of possible stall along with airspeed (Mumaw et al., 2016, January).
It can be said that the inadequate control action of the pilot may maximize instead of minimizing
the perception of pitch-up of the flight. In such a case, the aircrew will have no sensation to take
backwards tilt to aware them regarding the increasing pitch up attitude of the flight. As a result,
the pitch-up illusion may adversely affect the outputs of a usual procedure.
A deceptive response to the pitch-up illusion makes the aircraft's attitude to remain below the
horizon and develop an increasing airspeed and high rate of descent (Landman, Groen, Van
Paassen, Bronkhorst & Mulder, 2017). If a pilot reacts to the sensations without any reference to
a true flight instrument or visual horizon, then he is more likely to begin an unnecessary climb or
decent depending on whether the aircraft is decelerating or accelerating. Such illusions may
affect aviation safety as the automatic behaviors are performed without any intent or awareness
and also because of the confusion of how to perform a task (Kharoufah, Murray, Baxter & Wild,

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2018). However, to overcome these factors, the pilot, along with the crew members, are required
to monitor the instruments that are associated with vestibular systems. There is a need to monitor
the appropriate sources of information that will help in addressing such factors occurring due to
illusions (Lee & Kim, 2015).
Conclusion
The paper concluded the knowledge and understanding of the inflight illusions that are
associated with the vestibular system. Moreover, these illusions are found to generate a great
impact on the aircrew, which facilitates the mitigation of the various risks of adverse results.
Moreover, the paper helped in evaluating the facts associated with the "leans" as well as the
"pitch-up" illusions, which finally affects aviation safety. Moreover, the safety measures are of
great importance, and the strategies need to be developed to mitigate or reduce the adverse risks
from several illusions. A pitch-up illusion helps a pilot to identify that they are a greater distance
than their actual position.

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References
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