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Remote Pilot – Small Unmanned Aircraft Systems Study Guide 48
easily. A small amount of fluid in the mouth turns this mechanism off and the replacement of
needed body fluid is delayed.
Other steps to prevent dehydration include:
• Carrying a container in order to measure daily water intake.
• Staying ahead—not relying on the thirst sensation as an alarm. If plain water is not preferred,
add some sport drink flavoring to make it more acceptable.
• Limiting daily intake of caffeine and alcohol (both are diuretics and stimulate increased
production of urine).
Heatstroke
Heatstroke is a condition caused by any inability of the body to control its temperature. Onset of
this condition may be recognized by the symptoms of dehydration, but also has been known to be
recognized only upon complete collapse.
To prevent these symptoms, it is recommended that an ample supply of water be carried and used
at frequent intervals, whether thirsty or not. The body normally absorbs water at a rate of 1.2 to 1.5
quarts per hour. Individuals should drink one quart per hour for severe heat stress conditions or one
pint per hour for moderate stress conditions. For more information on water consumption, refer to
the “Dehydration” section of this chapter.
Drugs
The Federal Aviation Regulations include no specific references to medication usage. Title 14 of the
CFR prohibits acting as PIC or in any other capacity as a required pilot flight crewmember, while that
person:
1. Knows or has reason to know of any medical condition that would make the person unable to
meet the requirement for the medical certificate necessary for the pilot operation, or
2. Is taking medication or receiving other treatment for a medical condition that results in the
person being unable to meet the requirements for the medical certificate necessary for the
pilot operation.
Further, 14 CFR part 107 and 14 CFR part 91, sections 91.17 and 91.19 prohibit the use of any drug
that affects the person’s faculties in any way contrary to safety.
There are several thousand medications currently approved by the U.S. Food and Drug
Administration (FDA), not including OTC drugs. Virtually all medications have the potential for
adverse side effects in some people. Additionally, herbal and dietary supplements, sport and energy
boosters, and some other “natural” products are derived from substances often found in
medications that could also have adverse side effects. While some individuals experience no side
effects with a particular drug or product, others may be noticeably affected. The FAA regularly
reviews FDA and other data to assure that medications found acceptable for aviation duties do not
pose an adverse safety risk.
Some of the most commonly used OTC drugs, antihistamines and decongestants, have the potential
to cause noticeable adverse side effects, including drowsiness and cognitive deficits. The symptoms
associated with common upper respiratory infections, including the common cold, often suppress a
pilot’s desire to fly, and treating symptoms with a drug that causes adverse side effects only
compounds the problem. Particularly, medications containing diphenhydramine (e.g., Benadryl) are
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Remote Pilot – Small Unmanned Aircraft Systems Study Guide 49
known to cause drowsiness and have a prolonged half-life, meaning the drugs stay in one’s system
for an extended time, which lengthens the time that side effects are present.
Prior to each and every flight, all pilots must do a proper physical self -assessment to ensure safety.
A great mnemonic is IMSAFE, which stands for Illness, Medication, Stress, Alcohol, Fatigue, and
Emotion.
For the medication c omponent of IMSAFE, pilots need to ask themselves, “Am I taking any
medicines that might affect my judgment or make me drowsy? For any new medication, OTC or
prescribed, you should wait at least 48 hours after the first dose before flying to determine you do
not have any adverse side effects that would make it unsafe to operate an aircraft. In addition to
medication questions, pilots should also consider the following:
• Do not take any unnecessary or elective medications.
• Make sure you eat regular balanced meals.
• Bring a snack.
• Maintain good hydration - bring plenty of water.
• Ensure adequate sleep the night prior to the flight.
• Stay physically fit.
Alcohol
Alcohol impairs the efficiency of the human body.
[Figure 9-1] Studies have shown that consuming
alcohol is closely linked to performance deterioration.
Pilots must make hundreds of decisions, some of them
time-critical, during the course of a flight. The safe
outcome of any flight depends on the ability to make
the correct decisions and take the appropriate actions
during routine occurrences, as well as abnormal
situations. The influence of alcohol drastically reduces
the chances of completing a flight without incident.
Even in small amounts, alcohol can impair judgment,
decrease sense of responsibility, affect coo rdination,
constrict visual field, diminish memory, reduce
reasoning ability, and lower attention span. As little as
one ounce of alcohol can decrease the speed and
strength of muscular reflexes, lessen the efficiency of
eye movements while reading, and increase the
frequency at which errors are committed.
Impairments in vision and hearing can occur from
consuming as little as one drink.
While experiencing a hangover, a pilot is still under
the influence of alcohol. Although a pilot may think he
or she is functioning normally, motor and mental
response impairment is still present. Considerable
amounts of alcohol can remain in the body for over 16
hours, so pilots should be cautious about flying too soon after drinking.
Figure 9-1. Impairment scale with alcohol use.
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Intoxication is determined by the amount of alcohol in the bloodstream. This is usually measured as
a percentage by weight in the blood. 14 CFR part 91 requires that blood alcohol level be less than
.04 percent and that 8 hours pass between drinking alcohol and piloting an aircraft. A pilot with a
blood alcohol level of .04 percent or greater after 8 hours cannot fly until the blood alcohol falls
below that amount. Even though blood alcohol may be well below .04 percent, a pilot cannot fly
sooner than 8 hours after drinking alcohol. Although the regulations are quite specific, it is a good
idea to be more conservative than the regulations.
Vision and Flight
The more a pilot understands about the eyes and how they function, the easier it is to use vision
effectively and compensate for potential problems.
Scanning Techniques
To scan effectively, pilots must look from right to left or left to right. They should begin scanning at
the greatest distance an object can be perceived (top) and move inward toward the position of the
aircraft (bottom). For each stop, an area approximately 30° wide should be scanned. The duration of
each stop is based on the degree of detail that is required, but no stop should last longer than 2 to 3
seconds. When moving from one viewing point to the next, pilots should overlap the previous field
of view by 10°. [Figure 9-2]
Figure 9-2. Scanning techniques.
Remote Pilot – Small Unmanned Aircraft Systems Study Guide 51
Chapter 10:
Aeronautical Decision-Making and Judgment
Introduction
Aeronautical decision-making (ADM) is decision-making in a unique environment—aviation. It is a
systematic approach to the mental process used by pilots to consistently determine the best course of
action in response to a given set of circumstances. It is what a pilot intends to do based on the latest
information he or she has.
The importance of learning and understanding effective ADM skills cannot be overemphasized. While
progress is continually being made in the advancement of pilot training methods, aircraft equipment
and systems, and services for pilots, accidents still occur. Despite all the changes in technology to
improve flight safety, one factor remains the same: the human factor which leads to errors. It is
estimated that approximately 80 percent of all aviation accidents are related to human factors and the
vast majority of these accidents occur during landing (24.1 percent) and takeoff (23.4 percent).
ADM is a systematic approach to risk assessment and stress management. To understand ADM is to
also understand how personal attitudes can influence decision-making and how those attitudes can be
modified to enhance safety in the operation of a small UA. It is important to understand the factors
that cause humans to make decisions and how the decision-making process not only works, but can be
improved.
History of ADM
For over 25 years, the importance of good pilot judgment, or aeronautical decision-making (ADM), has
been recognized as critical to the safe operation of aircraft, as well as accident avoidance. The airline
industry, motivated by the need to reduce accidents caused by human factors, developed the first
training programs based on improving ADM. Crew resource management (CRM) training for flight
crews is focused on the effective use of all available resources: human resources, hardware, and
information supporting ADM to facilitate crew cooperation and improve decision-making. The goal of
all flight crews is good ADM and the use of CRM is one way to make good decisions.
Research in this area prompted the Federal Aviation Administration (FAA) to produce training directed
at improving the decision-making of pilots and led to current FAA regulations that require that
decision-making be taught as part of the pilot training curriculum. Aeronautical Decision Making and
Risk Management are topics that the FAA is required to test an applicant about for the issuance of an
sUAS certificate. ADM research, development, and testing culminated in 1987 with the publication of
six manuals oriented to the decision-making needs of variously rated pilots. These manuals provided
multifaceted materials designed to reduce the number of decision-related accidents. The effectiveness
of these materials was validated in independent studies where student pilots received such training in
conjunction with the standard flying curriculum. When tested, the pilots who had received ADM-
training made fewer inflight errors than those who had not received ADM training. The differences
were statistically significant and ranged from about 10 to 50 percent fewer judgment errors. In the
operational environment, an operator flying about 400,000 hours annually demonstrated a 54 percent
reduction in accident rate after using these materials for recurrency training.
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Contrary to popular opinion, good judgment can be taught. Tradition held that good judgment was a
natural by-product of experience, but as pilots continued to log accident-free flight hours, a
corresponding increase of good judgment was assumed. Building upon the foundation of conventional
decision-making, ADM enhances the process to decrease the probability of human error and increase
the probability of a safe flight. ADM provides a structured, systematic approach to analyzing changes
that occur during a flight and how these changes might affect the safe outcome of a flight. The ADM
process addresses all aspects of decision-making and identifies the steps involved in good decision-
making.
Steps for good decision-making are:
1. Identifying personal attitudes hazardous to safe flight.
2. Learning behavior modification techniques.
3. Learning how to recognize and cope with stress.
4. Developing risk assessment skills.
5. Using all resources.
6. Evaluating the effectiveness of one’s ADM skills.
Risk Management
The goal of risk management is to proactively identify
safety-related hazards and mitigate the associated
risks. Risk management is an important component of
ADM. When a pilot follows good decision -making
practices, the inherent risk in a flight is reduced or even
eliminated. The ability to make good decisions is based
upon direct or indirect experience and education. The
formal risk management decision -making process
involves six steps as shown in Figure 10-1.
Consider automotive seat belt use. In just tw o decades,
seat belt use has become the norm, placing those who
do not wear seat belts outside the norm, but this group
may learn to wear a seat belt by either direct or
indirect experience. For example, a driver learns
through direct experience about the value of wearing a
seat belt when he or she is involved in a car accident
that leads to a personal injury. An indirect learning
experience occurs when a loved one is injured during a
car accident because he or she failed to wear a seat
belt.
As you work through the ADM cycle, it is important to remember the four fundamental principles of
risk management.
1. Accept no unnecessary risk. Flying is not possible without risk, but unnecessary risk comes
without a corresponding return.
2. Make risk decisions at the appropriate level. Risk decisions should be made by the person
who can develop and implement risk controls.
3. Accept risk when benefits outweigh dangers (costs).
Figure 10-1. Risk management decision-making process.
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Remote Pilot – Small Unmanned Aircraft Systems Study Guide 53
4. Integrate risk management into planning at all levels. Because risk is an unavoidable part of
every flight, safety requires the use of appropriate and effective risk management not just in
the preflight planning stage, but in all stages of the flight.
While poor decision-making in everyday life does not always lead to tragedy, the margin for error in
aviation is thin. Since ADM enhances management of an aeronautical environment, all pilots should
become familiar with and employ ADM.
Crew Resource Management (CRM) and Single-Pilot Resource Management
While CRM focuses on pilots operating in crew environments, many of the concepts apply to single-
pilot operations. Many CRM principles have been successfully applied to single-pilot aircraft and led to
the development of Single-Pilot Resource Management (SRM). SRM is defined as the art and science of
managing all the resources available to a single pilot (prior to and during flight) to ensure the
successful outcome of the flight. SRM includes the concepts of ADM, risk management (RM), task
management (TM), automation management (AM), controlled flight into terrain (CFIT) awareness, and
situational awareness (SA). SRM training helps the pilot maintain situational awareness by managing
the automation and associated aircraft control and navigation tasks. This enables the pilot to
accurately assess and manage risk and make accurate and timely decisions.
SRM is all about helping pilots learn how to gather information, analyze it, and make decisions.
Hazard and Risk
Two defining elements of ADM are hazard and risk. Hazard is a real or perceived condition, event, or
circumstance that a pilot encounters. When faced with a hazard, the pilot makes an assessment of that
hazard based upon various factors. The pilot assigns a value to the potential impact of the hazard,
which qualifies the pilot’s assessment of the hazard—risk.
Therefore, risk is an assessment of the single or cumulative hazard facing a pilot; however, different
pilots see hazards differently.
Hazardous Attitudes and Antidotes
Being fit to fly depends on more than just a pilot’s physical condition and recent experience. For
example, attitude affects the quality of decisions. Attitude is a motivational predisposition to
respond to people, situations, or events in a given manner. Studies have identified five hazardous
attitudes that can interfere with the ability to make sound decisions and exercise authority properly:
anti-authority, impulsivity, invulnerability, macho, and resignation. [Figure 10-2]
Hazardous attitudes contribute to poor pilot judgment but can be effectively counteracted by
redirecting the hazardous attitude so that correct action can be taken. Recognition of hazardous
thoughts is the first step toward neutralizing them. After recognizing a thought as hazardous, the
pilot should label it as hazardous, then state the corresponding antidote. Antidotes should be
memorized for each of the hazardous attitudes so they automatically come to mind when needed.
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Remote Pilot – Small Unmanned Aircraft Systems Study Guide 54
Figure 10-2. The five hazardous attitudes identified through past and contemporary study.
Risk
During each flight, the single pilot makes many decisions under hazardous conditions. To fly safely,
the pilot needs to assess the degree of risk and determine the best course of action to mitigate the
risk.
Assessing Risk
For the single pilot, assessing risk is not as simple as it sounds. For example, the pilot acts as his or
her own quality control in making decisions. If a fatigued pilot who has flown 16 hours is asked if
he or she is too tired to continue flying, the answer may be “no.” Most pilots are goal oriented
and when asked to accept a flight, there is a tendency to deny personal limitations while adding
weight to issues not germane to the mission. For example, pilots of helicopter emergency
services (EMS) have been known (more than other groups) to make flight decisions that add
significant weight to the patient’s welfare. These pilots add weight to intangible factors (the
patient in this case) and fail to appropriately quantify actual hazards, such as fatigue or weather,
when making flight decisions. The single pilot who has no other crew member for consultation
must wrestle with the intangible factors that draw one into a hazardous position. Therefore, he
or she has a greater vulnerability than a full crew.
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Mitigating Risk
Risk assessment is only part of the equation.
One of the best ways single pilots can mitigate risk is to use the IMSAFE checklist to determine
physical and mental readiness for flying:
1. Illness—Am I sick? Illness is an obvious pilot risk.
2. Medication—Am I taking any medicines that might affect my judgment or make me drowsy?
3. Stress—Am I under psychological pressure from the job? Do I have money, health, or family
problems? Stress causes concentration and performance problems. While the regulations list
medical conditions that require grounding, stress is not among them. The pilot should
consider the effects of stress on performance.
4. Alcohol—Have I been drinking within 8 hours? Within 24 hours? As little as one ounce of
liquor, one bottle of beer, or four ounces of wine can impair flying skills. Alcohol also renders
a pilot more susceptible to disorientation and hypoxia.
5. Fatigue—Am I tired and not adequately rested? Fatigue continues to be one of the most
insidious hazards to flight safety, as it may not be apparent to a pilot until serious errors are
made.
6. Emotion—Am I emotionally upset?
The PAVE Checklist
Another way to mitigate risk is to perceive hazards. By incorporating the PAVE checklist into
preflight planning, the pilot divides the risks of flight into four categories: Pilot-in-command (PIC),
Aircraft, enVironment, and External pressures (PAVE) which form part of a pilot’s decision-making
process.
With the PAVE checklist, pilots have a simple way to remember each category to examine for risk
prior to each flight.
Once a pilot identifies the risks of a flight, he or she needs to decide whether the risk, or
combination of risks, can be managed safely and successfully. If not, make the decision to cancel the
flight. If the pilot decides to continue with the flight, he or she should develop strategies to mitigate
the risks. One way a pilot can control the risks is to set personal minimums for items in each risk
category. These are limits unique to that individual pilot’s current level of experience and
proficiency.
P = Pilot-in-Command (PIC)
The pilot is one of the risk factors in a flight. The pilot must ask, “Am I ready for this flight?” in
terms of experience, recency, currency, physical, and emotional condition. The IMSAFE checklist
provides the answers.
A = Aircraft
What limitations will the aircraft impose upon the trip? Ask the following questions:
• Is this the right aircraft for the flight?
• Am I familiar with and current in this aircraft?
• Can this aircraft carry the planned load?
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V = EnVironment
Weather
Weather is a major environmental consideration. Earlier it was suggested pilots set their own
personal minimums, especially when it comes to weather. As pilots evaluate the weather for a
particular flight, they should consider the following:
• What is the current ceiling and visibility?
• Consider the possibility that the weather may be different than forecast.
• Are there any thunderstorms present or forecast?
• If there are clouds, is there any icing, current or forecast? What is the temperature/dew point
spread and the current temperature at altitude?
Terrain
Evaluation of terrain is another important component of analyzing the flight environment.
Airspace
Check the airspace and any temporary flight restriction (TFRs).
E = External Pressures
External pressures are influences external to the flight that create a sense of pressure to
complete a flight—often at the expense of safety. Factors that can be external pressures include
the following:
• The desire to demonstrate pilot qualifications
• The desire to impress someone (Probably the two most dangerous words in aviation are
“Watch this!”)
• The pilot’s general goal-completion orientation
• Emotional pressure associated with acknowledging that skill and experience levels may be
lower than a pilot would like them to be. Pride can be a powerful external factor!
Managing External Pressures
Management of external pressure is the single most important key to risk management because
it is the one risk factor category that can cause a pilot to ignore all the other risk factors.
The use of personal standard operating procedures (SOPs) is one way to manage external
pressures. The goal is to supply a release for the external pressures of a flight.
Human Factors
Why are human conditions, such as fatigue, complacency and stress, so important in aviation? These
conditions, along with many others, are called human factors. Human factors directly cause or
contribute to many aviation accidents and have been documented as a primary contributor to more
than 70 percent of aircraft accidents.
Typically, human factor incidents/accidents are associated with flight operations but recently have also
become a major concern in aviation maintenance and air traffic management as well. Over the past
several years, the FAA has made the study and research of human factors a top priority by working
closely with engineers, pilots, mechanics, and ATC to apply the latest knowledge about human factors
in an effort to help operators and maintainers improve safety and efficiency in their daily operations.
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Human factors science, or human factors technologies, is a multidisciplinary field incorporating
contributions from psychology, engineering, industrial design, statistics, operations research, and
anthropometry. It is a term that covers the science of understanding the properties of human
capability, the application of this understanding to the design, development and deployment of
systems and services, and the art of ensuring successful application of human factor principles into all
aspects of aviation to include pilots, ATC, and aviation maintenance. Human factors is often considered
synonymous with CRM or maintenance resource management (MRM) but is really much broader in
both its knowledge base and scope. Human factors involves gathering research specific to certain
situations (i.e., flight, maintenance, stress levels, knowledge) about human abilities, limitations, and
other characteristics and applying it to tool design, machines, systems, tasks, jobs, and environments
to produce safe, comfortable, and effective human use. The entire aviation community benefits greatly
from human factors research and development as it helps better understand how humans can most
safely and efficiently perform their jobs and improve the tools and systems in which they interact.
The Decision-Making Process
An understanding of the decision-making process provides the pilot with a foundation for developing
ADM and SRM skills. While some situations, such as engine failure, require an immediate pilot
response using established procedures, there is usually time during a flight to analyze any changes that
occur, gather information, and assess risks before reaching a decision.
Risk management and risk intervention is much more than the simple definitions of the terms might
suggest. Risk management and risk intervention are decision-making processes designed to
systematically identify hazards, assess the degree of risk, and determine the best course of action.
These processes involve the identification of hazards, followed by assessments of the risks, analysis of
the controls, making control decisions, using the controls, and monitoring the results.
The steps leading to this decision constitute a decision-making process. Three models of a structured
framework for problem-solving and decision-making are the 5P, the 3P using PAVE, CARE and TEAM,
and the DECIDE models. They provide assistance in organizing the decision process. All these models
have been identified as helpful to the single pilot in organizing critical decisions.
Single-Pilot Resource Management (SRM)
Single-Pilot Resource Management (SRM) is about how to gather information, analyze it, and make
decisions. Learning how to identify problems, analyze the information, and make informed and
timely decisions is not as straightforward as the training involved in learning specific maneuvers.
Learning how to judge a situation and “how to think” in the endless variety of situations
encountered while flying out in the “real world” is more difficult.
There is no one right answer in ADM, rather each pilot is expected to analyze each situation in light
of experience level, personal minimums, and current physical and mental readiness level, and make
his or her own decision.
Perceive, Process, Perform (3P) Model
The Perceive, Process, Perform (3P) model for ADM offers a simple, practical, and systematic
approach that can be used during all phases of flight. To use it, the pilot will:
• Perceive the given set of circumstances for a flight
• Process by evaluating their impact on flight safety
• Perform by implementing the best course of action
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Use the Perceive, Process, Perform, and Evaluate method as a continuous model for every
aeronautical decision that you make. Although human beings will inevitably make mistakes,
anything that you can do to recognize and minimize potential threats to your safety will make you a
better pilot.
Depending upon the nature of the activity and the time available, risk management processing can
take place in any of three timeframes. [Figure 10-3] Most flight training activities take place in the
“time-critical” timeframe for risk management. The six steps of risk management can be combined
into an easy-to-remember 3P model for practical risk management: Perceive, Process, Perform with
the PAVE, CARE and TEAM checklists. Pilots can help perceive hazards by using the PAVE checklist
of: Pilot, Aircraft, enVironment, and External pressures. They can process hazards by using the CARE
checklist of: Consequences, Alternatives, Reality, External factors. Finally, pilots can perform risk
management by using the TEAM choice list of: Transfer, Eliminate, Accept, or Mitigate.
Figure 10-3. Risk management processing can take place in any of three timeframes.
PAVE Checklist: Identify Hazards and Personal Minimums
In the first step, the goal is to develop situational awareness by perceiving hazards, which are
present events, objects, or circumstances that could contribute to an undesired future event. In
this step, the pilot will systematically identify and list hazards associated with all aspects of the
flight: Pilot, Aircraft, enVironment, and External pressures, which makes up the PAVE checklist.
[Figure 10-4] All four elements combine and interact to create a unique situation for any flight.
Pay special attention to the pilot-aircraft combination, and consider whether the combined
“pilot-aircraft team” is capable of the mission you want to fly. For example, you may be a very
experienced and proficient pilot, but your weather flying ability is still limited if you are flying an
unfamiliar aircraft. On the other hand, you may have a new technically advanced aircraft that you
have flown for a considerable amount of time.
Figure 10-4. A real-world example of how the 3P model guides decisions on a cross-country trip using the PAVE checklist.