Phase II Human/Machine Task Assignment Assignment:
Cockpit Redesign for Accommodation of Disabled Pilots
Chris C. Beeney
January 28, 2019
Embry Riddle Aeronautical University
UNSY 431: Unmanned Systems Human Factors Considerations
Definition of System Tasks
In this section, the individual subtasks in the cockpit that are used for operating a plane will be
identified. However, there are too many components to address within the given time constraints
so three components have been selected. These components are designed with a reactive
approach because the pilot is expected to conform to the equipment (Salvendy, 2012). The three
subtasks include operation of the yoke, operation of the rudder, and operation of the brake.
These subtasks are highlighted in Table 1 and addressed in more detail in the following
paragraphs.
identified. However, there are too many components to address within the given time constraints
so three components have been selected. These components are designed with a reactive
approach because the pilot is expected to conform to the equipment (Salvendy, 2012). The three
subtasks include operation of the yoke, operation of the rudder, and operation of the brake.
These subtasks are highlighted in Table 1 and addressed in more detail in the following
paragraphs.
The yoke is the plane’s steering wheel (Hawkins, 2014). The yoke is used to ascend, descend,
bank left, or bank right. Given enough runway and velocity, a plane will lift into the air due to
physics but the yoke is required to ascend to a cruising altitude. Likewise, the yoke is required
to descend towards the ground when landing. Additionally, part of the turning feature is that the
yoke enables the plane to bank left or right. The cognitive requirement that is needed for using
the yoke involves the pilot identifying the direction that he or she needs to take the plane using
their visual organ along with their working memory. Sometimes the pilot will be given direction
by ground control and this requires use of the auditory organ. Once the direction has been
determined, the pilot must physically touch the yoke to accomplish the maneuver. The
physiological requirement for moving the plane in the desired direction is to either push, pull, or
turn the yoke with their hands in order to steer the plane. The yoke gives haptic feedback to the
pilot due to forces acting against the external components of the plane (the ailerons) which can
cause fatigue to the pilot’s arms as well. Pilots must have a sturdy grip on the yoke in order to
avoid crashing (Hawkins, 2014).
bank left, or bank right. Given enough runway and velocity, a plane will lift into the air due to
physics but the yoke is required to ascend to a cruising altitude. Likewise, the yoke is required
to descend towards the ground when landing. Additionally, part of the turning feature is that the
yoke enables the plane to bank left or right. The cognitive requirement that is needed for using
the yoke involves the pilot identifying the direction that he or she needs to take the plane using
their visual organ along with their working memory. Sometimes the pilot will be given direction
by ground control and this requires use of the auditory organ. Once the direction has been
determined, the pilot must physically touch the yoke to accomplish the maneuver. The
physiological requirement for moving the plane in the desired direction is to either push, pull, or
turn the yoke with their hands in order to steer the plane. The yoke gives haptic feedback to the
pilot due to forces acting against the external components of the plane (the ailerons) which can
cause fatigue to the pilot’s arms as well. Pilots must have a sturdy grip on the yoke in order to
avoid crashing (Hawkins, 2014).
The rudder controls whether the plane flies left or right by assisting with pointing the nose of the
aircraft (Hall, 2018). Although planes usually bank left or right with the yoke, it can be difficult
to line up the aircraft to a particular path such as a runway while attempting to land; the rudder
helps the pilot make fine adjustments to the direction of flight to achieve this goal. The cognitive
requirement that is needed for using the rudder involves the pilot identifying the direction that
he or she needs to adjust the nose of the plane towards. This is accomplished primarily with the
visual organ but they may use the auditory organ if receiving directions from a control tower
during landing. The working memory is used to calculate how much force to apply to the rudder
as well. Once the direction has been determined, the pilot must physically touch the rudder to
accomplish the maneuver. The physiological requirement for moving the plane’s nose in the
desired direction is to depress the left or right rudder pedal; this is done with the pilot’s feet. The
rudder gives haptic feedback to the pilot due to forces acting against the external components
of the plane (the rudder itself) which can cause fatigue to the pilot’s legs with prolonged use.
Pilots must be able to reach the pedals and depress them in order to operate the rudder
(Hawkins, 2014).
aircraft (Hall, 2018). Although planes usually bank left or right with the yoke, it can be difficult
to line up the aircraft to a particular path such as a runway while attempting to land; the rudder
helps the pilot make fine adjustments to the direction of flight to achieve this goal. The cognitive
requirement that is needed for using the rudder involves the pilot identifying the direction that
he or she needs to adjust the nose of the plane towards. This is accomplished primarily with the
visual organ but they may use the auditory organ if receiving directions from a control tower
during landing. The working memory is used to calculate how much force to apply to the rudder
as well. Once the direction has been determined, the pilot must physically touch the rudder to
accomplish the maneuver. The physiological requirement for moving the plane’s nose in the
desired direction is to depress the left or right rudder pedal; this is done with the pilot’s feet. The
rudder gives haptic feedback to the pilot due to forces acting against the external components
of the plane (the rudder itself) which can cause fatigue to the pilot’s legs with prolonged use.
Pilots must be able to reach the pedals and depress them in order to operate the rudder
(Hawkins, 2014).
The brake is controlled with a toe pedal above the rudder. The brake is used to slow down and
stop the plane on the ground. Without a brake, the plane would start moving as soon as the
engine is turned on and would not be able to stop after landing without some other mechanism
such as a net. The cognitive requirement that is needed for using the brake involves the pilot
identifying when the plane needs to not be in motion. This is accomplished with their visual
organ as well as their auditory organ given that ground control advises them to hold before
takeoff. The pilot must use their working memory to determine how much force to apply in
order to keep the plane stationary as well as to slow the plane when landing. The pilot must
physically touch the brake to accomplish the action. The physiological requirement to achieve
braking is to depress the brake pedal with their foot. The brake gives haptic feedback as kinetic
friction causes the wheels of the plane to slow and then stop; this could cause fatigue to the
pilot’s leg. Pilots must be able to reach the brake and depress it hard enough to keep the plane
from moving when stationary.
stop the plane on the ground. Without a brake, the plane would start moving as soon as the
engine is turned on and would not be able to stop after landing without some other mechanism
such as a net. The cognitive requirement that is needed for using the brake involves the pilot
identifying when the plane needs to not be in motion. This is accomplished with their visual
organ as well as their auditory organ given that ground control advises them to hold before
takeoff. The pilot must use their working memory to determine how much force to apply in
order to keep the plane stationary as well as to slow the plane when landing. The pilot must
physically touch the brake to accomplish the action. The physiological requirement to achieve
braking is to depress the brake pedal with their foot. The brake gives haptic feedback as kinetic
friction causes the wheels of the plane to slow and then stop; this could cause fatigue to the
pilot’s leg. Pilots must be able to reach the brake and depress it hard enough to keep the plane
from moving when stationary.
Table 1:
Summary of the Current System Task Assignments
Task
|
Brief Description
|
Human or Machine Assignment
|
Cognitive Requirements
|
Physiological Requirements
|
Brake
|
Brake pedal stops plane
|
Human
|
Working memory
|
Depress pedal with foot
|
Rudder
|
Rudder pedal assists with turns
|
Human
|
Working memory
|
Depress pedal with foot
|
Steer
|
Yoke steers plane
|
Human
|
Working memory
|
Push/pull/turn yoke with hands
|
Note: These subtasks were retrieved from general knowledge of how to fly a plane.
Proposed Task Assignment Using Fitt’s Principles
In this section, Fitt’s principles will be used to determine which of the three subtasks above
should be re-assigned to be performed by a machine. Paul Fitts created a list of 11 statements
describing which actions are performed better by a machine or by a human
(de Winter, & Dodou, 2014). A brief summary of the subtasks addressed in this paper can
be seen in Table 2 but will be discussed in detail in the following paragraphs.
should be re-assigned to be performed by a machine. Paul Fitts created a list of 11 statements
describing which actions are performed better by a machine or by a human
(de Winter, & Dodou, 2014). A brief summary of the subtasks addressed in this paper can
be seen in Table 2 but will be discussed in detail in the following paragraphs.
The yoke is required in order to steer the plane. Directionality is very important when flying a
plane and requires an understanding of the surrounding environment. But a steady course could
be automated. Because of this, a human should be in control of the yoke but may be assisted by
a machine using autopilot. A semi-automated yoke would offer the pilot stabilized control; the
plane will return to wings level mode after the yoke is used to steer in the desired direction
(Barnhart, Marshall, Most, & Shappee, 2016). Fitt’s second statement applies when arguing
for human control because pattern recognition is crucial for navigating; especially when
recognizing a runway at night. Fitt’s third statement applies when arguing for human control
because improvisation is sometimes needed such as unexpected collision avoidance. Fitt’s fifth
and sixth statements apply (often together) when arguing for human control because deductive
reasoning and the ability to make judgements are important aspects of steering the plane during
times such as course correcting for inclement weather on the horizon (de Winter, et. al., 2014).
Fitt’s first statement applies when arguing for machine control because the autopilot can
smoothly apply the needed force to re-align the plane with the horizon precisely.
plane and requires an understanding of the surrounding environment. But a steady course could
be automated. Because of this, a human should be in control of the yoke but may be assisted by
a machine using autopilot. A semi-automated yoke would offer the pilot stabilized control; the
plane will return to wings level mode after the yoke is used to steer in the desired direction
(Barnhart, Marshall, Most, & Shappee, 2016). Fitt’s second statement applies when arguing
for human control because pattern recognition is crucial for navigating; especially when
recognizing a runway at night. Fitt’s third statement applies when arguing for human control
because improvisation is sometimes needed such as unexpected collision avoidance. Fitt’s fifth
and sixth statements apply (often together) when arguing for human control because deductive
reasoning and the ability to make judgements are important aspects of steering the plane during
times such as course correcting for inclement weather on the horizon (de Winter, et. al., 2014).
Fitt’s first statement applies when arguing for machine control because the autopilot can
smoothly apply the needed force to re-align the plane with the horizon precisely.
The rudder is required to assist in directing the plane appropriately. The plane would be more
difficult to align to the planned trajectory without the rudder. Because the rudder consists of
reactive minute actions, it could be automated entirely. As with the yoke, stabilized control
would afford the plane with the appropriate level of rudder adjustments without human
intervention. Fitt’s second statement arguing for machine control applies because rudder control
is a repetitive routine task. Fitt’s fourth statement arguing for machine control applies because
the machine can perform complex calculation to compensate for cross winds if it determines
that the plane is off planned course. Fitt’s fifth statement applies when arguing for machine
control because machines can handle many tasks at once easily so calculating wind speed and
adjusting the rudder while checking planned trajectory against GPS will not be an issue.
difficult to align to the planned trajectory without the rudder. Because the rudder consists of
reactive minute actions, it could be automated entirely. As with the yoke, stabilized control
would afford the plane with the appropriate level of rudder adjustments without human
intervention. Fitt’s second statement arguing for machine control applies because rudder control
is a repetitive routine task. Fitt’s fourth statement arguing for machine control applies because
the machine can perform complex calculation to compensate for cross winds if it determines
that the plane is off planned course. Fitt’s fifth statement applies when arguing for machine
control because machines can handle many tasks at once easily so calculating wind speed and
adjusting the rudder while checking planned trajectory against GPS will not be an issue.
The brake is important for keeping the aircraft from rolling before and after flight. Usually the
plane will need to taxi to the runway and then wait for ground control to authorize the flight
once it is safe. Without brakes, the plane would begin to accelerate as soon as the engine is
turned on and take off regardless of whether the pilot has navigated to the runway or not. Upon
landing, the brakes are essential for stopping the plane safely. Without artificial intelligence to
determine when to apply brakes, these are best left to the human. Fitt’s third statement applies
when arguing for human control because takeoff procedures are usually flexible; the pilot must
wait until ground control clears the takeoff. Fitt’s fourth statement applies when arguing for
human control because the pilot must recognize the appropriate time to apply the brakes.
plane will need to taxi to the runway and then wait for ground control to authorize the flight
once it is safe. Without brakes, the plane would begin to accelerate as soon as the engine is
turned on and take off regardless of whether the pilot has navigated to the runway or not. Upon
landing, the brakes are essential for stopping the plane safely. Without artificial intelligence to
determine when to apply brakes, these are best left to the human. Fitt’s third statement applies
when arguing for human control because takeoff procedures are usually flexible; the pilot must
wait until ground control clears the takeoff. Fitt’s fourth statement applies when arguing for
human control because the pilot must recognize the appropriate time to apply the brakes.
Table 2
Summary of the Proposed System Task Assignments
Task
|
Human Assignment
|
Machine Assignment
|
Brake
|
x
| |
Rudder
|
x
| |
Steer
|
x
|
x
|
Potential Design or Training Challenges Associated with Proposed Task Assignment
Digital control of the airplane should be possible in place of a traditional yoke and rudder. The
technology is there for unmanned systems and so it should be easy to implement into a manned system.
This method would suit those with one arm amputation because they can still control the digital yoke
with one hand. The brake could be an added button that needs to be controlled by hand; probably a
physical button because it is a very important feature. Because the technology for stabilized control is
utilized primarily for small unmanned aerial units in their handheld ground station controllers along
with onboard autopilot, traditionally taught pilots may not be able to control the plane digitally without
proper training. To make this effective for amputees, the screen will need to be mostly digital rather
than housing physical buttons so that one hand will be able to tap on the appropriate icons. The actual
screen could be set up like a video game controller, with a left, right, up, and down D-Pad
configuration. As an added feature, the device could include a field for entering or selecting altitude to
facilitate ascent or descent using the autopilot.
technology is there for unmanned systems and so it should be easy to implement into a manned system.
This method would suit those with one arm amputation because they can still control the digital yoke
with one hand. The brake could be an added button that needs to be controlled by hand; probably a
physical button because it is a very important feature. Because the technology for stabilized control is
utilized primarily for small unmanned aerial units in their handheld ground station controllers along
with onboard autopilot, traditionally taught pilots may not be able to control the plane digitally without
proper training. To make this effective for amputees, the screen will need to be mostly digital rather
than housing physical buttons so that one hand will be able to tap on the appropriate icons. The actual
screen could be set up like a video game controller, with a left, right, up, and down D-Pad
configuration. As an added feature, the device could include a field for entering or selecting altitude to
facilitate ascent or descent using the autopilot.
Reference List
Barnhart, R. K., Marshall, D. M., Most M.T., & Shappee, E. (2016). Introduction to unmanned
aircraft systems. (2nd ed.). Boca Raton, FL: CRC Press, Taylor & Francis Group.
aircraft systems. (2nd ed.). Boca Raton, FL: CRC Press, Taylor & Francis Group.
de Winter, J. C., , F., & Dodou, D. (2014). Why the fitts list has persisted throughout the history of
function allocation. Cognition, Technology & Work, 16(1), 1-11.
doi:http://dx.doi.org.ezproxy.libproxy.db.erau.edu/10.1007/s10111-011-0188-1
function allocation. Cognition, Technology & Work, 16(1), 1-11.
doi:http://dx.doi.org.ezproxy.libproxy.db.erau.edu/10.1007/s10111-011-0188-1
Hall, N. (Apr. 5, 2018). Vertical Stabilizer - Rudder. NASA. Retrieved from
https://www.grc.nasa.gov/www/k-12/airplane/rud.html
https://www.grc.nasa.gov/www/k-12/airplane/rud.html
Hawkins, K. (Aug. 14, 2014). How do amputees fly planes? BBC News. Retrieved from
https://www.bbc.com/news/magazine-28785171
https://www.bbc.com/news/magazine-28785171
Salvendy, G. (Ed.). (2012). Handbook of human factors and ergonomics. Retrieved from
https://ebookcentral.proquest.com
https://ebookcentral.proquest.com
