Human Factors

Area of Operation II. Task A

Overview

• Aeronautical Decision Making
• Risk Management
• Crew Resource Management (CRM) and Single Pilot-Resource Management
• Hazard and Risk
• Human Factors and Behavior
• Decision-Making Process
• Situational Awareness
• Aeromedical and Physiological issues

Back Story

Human factors are elements that affect individuals differently and profoundly impact their decision-making. An example of this was the flight of a Beechcraft King Air equipped with deicing and anti-icing. The pilot deliberately flew into moderate to severe icing conditions while ducking under cloud cover. A prudent pilot would assess the risk a high and beyond the capabilities of the aircraft, yet the pilot did the opposite.

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Aeronautical Decision Making (ADM)

What is it?

• It’s 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.

Why is this important?

• The need to reduce accidents caused by human factors has become more apparent over the past 25 years. The importance of good judgement has been recognized as critical to the safe operation of aircraft and accident avoidance.

Steps for good decision-making:

• Identify personal attitudes hazardous to safe flight
• Learn behavior modification techniques
• Learn how to recognize and cope with stress
• Develop risk assessment skills

Perceive, Process, Perform (3P) Model

Risk Management

Goal: proactively identify safety-related hazards and mitigate the associated risks.

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The fundamental principles of risk management are:

• Accept no unnecessary risk
• Make risk decisions at the appropriate level – as PIC you are responsible for making those risk decisions
• Accept risk when the benefits outweigh the dangers

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Crew Resource Management and Single-Pilot Resource Management

• Crew Resource Management (CRM) mainly focuses on pilots operating in crew environments but can be applied to single-pilot operations
• Single-Pilot Resource Management (SRM) is the art and science of managing all the resources available to a single pilot – these can be both on board and outside sources
• Includes concepts of:
• ADM
• Risk management
• Task management
• Automation management
• Controlled flight into terrain (CFIT) awareness
• Situational awareness
• SRM training allows pilots to maintain situational awareness by managing the automation, aircraft control, and navigation tasks

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Hazards and Risks

Hazards: real or perceived condition, event, or circumstance that a pilot encounters

• 5 Hazardous Attitudes

Risk: an assessment of the single cumulative hazard facing a pilot (different pilots see hazards differently)

• Assessing Risk
• Mitigating Risk
• Pave Checklist

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5 Hazardous Attitudes

1. Anti-authority: “Don’t tell me what to do”

Follow the rules. They are usually right.

• Impulsivity: “Do it quickly”

Not so fast. Think first.

• Invulnerability: “It won't happen to me”

It could happen to me.

• Macho: “I can do it”

Taking chances is foolish

• Resignation: “What’s the use?”

I’m not helpless. I can make a difference

Which hazardous attitudes do you relate to?

Assessing Risk

Risk Assessing Guidelines:

• Probable – an event will occur several times
• Occasional – an event will probably occur sometime
• Remote – an event is unlikely to occur, but is possible
• Improbable – an event is highly unlikely to occur

Severity of an Event:

• Catastrophic – results in fatalities, total loss
• Critical – severe injury, major damage
• Marginal – minor injury, minor damage
• Negligible – less than minor injury, less than minor system damage

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Mitigating Risks

• The PAVE checklist is another way to mitigate risk
• Pilot
• Aircraft
• enVironment
• External pressures

Pilot

• IMSAFE Checklist
1. Illness – Am I sick?
2. Medication – Am I taking any medication that might affect my judgment?
3. Stress – Am I under psychological pressure from the job? Are they external stress factors that could be affecting me?
4. Alcohol – Have I been drinking within 8 hours? Within 24 hours?
5. Fatigue – Am I tired and not adequately rested?
6. Emotion – Am I emotionally upset?

Mitigating Risks

Aircraft

• We ask the following questions:
• Is this the right aircraft for the flight?
• Am I familiar with an current in this aircraft?
• Is this aircraft equipped for the flight? Instruments? Lights? Navigation and communication equipment adequate?
• Can this aircraft use the runways available for the trip with an adequate margin of safety under the conditions to be flown?
• Can this aircraft carry the planned load?
• Can this aircraft operate at the altitudes needed for the trip?
• Does this aircraft have sufficient fuel capacity, with reserves, for trip legs planned?
• Does the fuel quantity delivered match the fuel quantity ordered?

Mitigating Risks

enVironment

• N - NOTAMs
• W - Weather
• K - Known ATC delays
• R – Runway lengths
• A - Alternates
• F – Fuel
• T – Take off and Landing Distances

Mitigating Risks

External Pressures

• Someone waiting at the airport for the flight’s arrival
• The desire to demonstrate pilot qualifications
• The desire to impress someone
• The pilot’s general goal-completion orientation
• Emotional pressure

Managing External Pressures

• Allow time in a trip for an extra fuel stop
• Have alternate planes for a late arrival or backup airline reservation
• Plan to leave early to make it to the destination
• Manage passenger expectations
• Eliminate pressure to return home

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Human Factors and Behaviors

• Human factors directly cause or contribute to many aviation accidents
• Associated with flight operations, aviation maintenance, and air traffic management
• Involves gathering research specific to certain situations about human abilities, limitations, and other characteristics and applying it
• Human Behavior – studies have been done to try to demonstrate an individuals predisposition to taking risks and the level of an individual’s involvement in accidents.
• Five traits in pilots prone to accidents”
1. Have disdain toward rules
2. Have a very high correlation between accidents on their flying records and safety violations on their driving records
3. Frequently fall into the “thrill and adventure seeking” personality category
4. Are impulsive rather than methodical and disciplined
5. Have a disregard for or tend to under utilize outside sources on information (co pilots, flight attendants, flight instructors, ATC)

The Decision-Making Process

The 5 Ps – Aid in the go/no go decision

• Plan – basic elements of cross-country planning
• Plane – array of mechanical and cosmetic issues that are identifiable
• Pilot – IMSAFE checklist before each flight
• Passengers – interaction with the pilot
• Programming – up to date avionics and personal capabilities

The Decision-Making Process

CARE Checklist

• Consequences – departing after a full workday creates fatigue and pressure
• Alternatives – delay until morning; reschedule meeting; drive
• Reality – Dangers and distractions of fatigue could lead to an accident
• External pressures – business meeting at a destination might influence me

TEAM Checklist

• Transfer – Should this risk decision be transferred to someone else?
• Eliminate – Is there a way to eliminate the hazard?
• Accept – Do the benefits of accepting risk outweigh the costs?
• Mitigate – What can you do to mitigate the risk?

DECIDE Model

• Detect the problem/change
• Estimate the need to react
• Choose a course of action
• Identify solutions
• Do the necessary actions
• Evaluate the actions

Situational Awareness

The accurate perception and understanding of all the factors and conditions within the five fundamental risk elements that affect safety before, during, and after the flight.

• Distractions, fatigue, and stress can decrease situational awareness
• Experience, discipline, and training can counteract this

Controlled Flight Into Terrain (CFIT)

What is it?

• Unintentional collision with terrain while an aircraft is under positive control.

When is it most common?

• During the approach or landing phase of flight

Why does it happen?

• Loss of situational awareness – failing to know at all times what the aircraft’s position is and how it relates to altitude of the surface below

How can it be avoided?

• Safety Risk Management – knowing what you’re getting into and understanding what capabilities and resources you have to ensure a safe flight

Aeromedical and Physiological Issues

Hypoxia

• Hypoxia means “ reduced oxygen” that can be caused by insufficient supply of oxygen, inadequate transpiration of oxygen, or the inability to use oxygen.

Types of Hypoxia:

• Hypoxic hypoxia – insufficient oxygen as a whole
• Cause: Insufficient Oxygen Pressure
• Corrective Action: Descend to a lower altitude or use supplemental oxygen
• Hypemic hypoxia – blood is not able to take and transport oxygen to the cells
• Cause: Carbon monoxide Poisoning
• Corrective Action: Turn off cabin heat or avoid flying

Hypoxia

• Stagnant hypoxia – oxygen-rich blood is not moving
• Cause: G-forces
• Corrective Action: promote blood flow by reducing G’s
• Histotoxic hypoxia – Cells are unable to use oxygen due to drugs or alcohol
• Cause: Drugs and Alcohol
• Corrective Action: DON’T FLY

Symptoms

Hyperventilation

Excessive rate and depth of respiration leading to abnormal loss of carbon dioxide form the blood.

• Cause: anxiety, stress, increased breathing, lack of oxygen at higher altitudes
• Corrective action: slow down your breathing rate by breathing into a paper bag or talking out loud

Symptoms:

• Visual impairment
• Unconsciousness
• Lightheaded
• Tingling sensations
• Hot/cold sensations
• Muscle spasms

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Hypothermia

What is Hypothermia?

• Body temperature drops below 95°F (35°C)
• Caused by prolonged cold exposure or immersion

Symptoms

• Mild: Shivering, confusion
• Severe: slurred speech, weak pulse, unconsciousness

Relevance to Aviation

• Pilots and passengers are at risk during off-airport landings in cold environments
• Extended exposure during preflight inspections or open cockpits can lead to hypothermia

Prevention and Response

• Dress appropriately for the weather, even during short flights
• Keep emergency cold-weather gear in the aircraft

Middle Ear and Sinus Problems

• Gas Expansion: During climbs and descents, trapped gas in body cavities expands due to pressure differences
• Can cause ear and sinus pain, along with temporary hearing loss.
• Middle Ear Mechanics:
• The middle ear is separated from the external ear canal by the eardrum
• Pressure differences during climbs make the eardrum bulge outward; during descent, it bulges inward.
• Sinus Pressure and Blockages:
• Congestion from colds, sinusitis, or allergies can block equalization, especially during descent, causing sinus pain.
• Prevention and Remedies:
• Avoid flying with respiratory infections or allergies to prevent painful blockages
• Decongestants may not be effective and can impair performance

Spatial Disorientation

What is it?

• Lack of orientation regarding the airplane’s position, attitude, or movement in space

Three Sensory Systems:

• Vestibular System: Inner ear organs sense balance and position
• Somatosensory System: Nerves in skin, muscles, and joints sense position based on gravity and feeling
• Visual System: Eyes provide orientation based on visual cues

Illusions in Flight

• Without visual references, forces during flight can create false impressions of aircraft orientation

Prevention of Disorientation

• Avoid flying in low visibility unless trained in instrument flight
• Rely on flight instruments to prevent illusions and disorientation

Illusions

• I – Inversion
• A sudden change from climb to level flight can create the sensation of tumbling backward, leading the pilot to push the aircraft into a nose low attitude
• C – Coriolis
• Head movement during a prolonged turn creates the false sensation of turning on a different axis, potentially leading to dangerous maneuvers
• E – Elevator
• Upward acceleration feels like a climb, causing the pilot to push the nose down; downward acceleration causes the opposite effect
• F – False Horizon
• Misleading visual cues such as sloping clouds, ground lights, or stars can create a false sense of horizon, leading the pilot to align the aircraft incorrectly and potentially causing dangerous attitudes.

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Illusions

• L – Leans
• Occurs when a pilot levels the aircraft after an unnoticed gradual turn, creating the false sensation of banking in the opposite direction
• A – Autokinesis
• Staring at a stationary light for an extended period can create the illusion that the light is moving, leading a pilot to mistakenly align the aircraft with it risking loss of control
• G – Graveyard Spiral
• A pilot in a prolonged turn may feel level and mistakenly descend into a tighter spiral while trying to climb, resulting in loss of control
• S – Somatogravic
• Rapid acceleration feels like a nose-up attitude, causing the pilot to push the aircraft into a dive; rapid deceleration can cause the opposite effect

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Optical Illusions

Vision is crucial for safe flight, especially during landing when transitioning from instruments to visual cues

Runway Width:

• A narrower runway can make the aircraft appear higher, leading to a lower approach
• A wider runway can create the opposite effect, risking hard landings or overshooting

Runway Terrain Slopes:

• Upsloping runways or terrain can create the illusion of higher altitude, causing a lower approach
• Down sloping surfaces can lead to the opposite illusion

Featureless Terrain:

• Approaches over featureless terrain can lead pilots to believe they are higher than they are

Optical Illusions

Water Refraction:

• Rain on the windscreen can make the horizon appear lower

Haze

• Creates the illusion of greater distance and height, causing pilots to be low on approach

Fog

• Can create the illusion of pitching up

Ground Lighting

• Lights along roads or moving trains can be mistaken for runway lights

Motion Sickness

Motion sickness is caused by the brain receiving conflicting sensory signals about the body’s state, often during initial flights.

Symptoms

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Contributing Factors

• Anxiety and stress can increase the likelihood of motion sickness, especially during early flight lessons

Managing Motion Sickness

• Inform the flight instructor if prone to motion sickness
• Avoid turbulent conditions, starting with shorter flights, opening fresh air vents, focusing on external objects, and minimize head movements

Carbon Monoxide Poisoning

Characteristics

• CO is a colorless, odorless gas produced by internal combustion engines
• Attaches to hemoglobin 200 time more easily than oxygen, causing hypemic hypoxia by preventing oxygen transport

Duration In The Body

• 48 hours

Where can it come from?

• Can enter the cabin through heater and defrost vents (cabin heat), especially if the engine exhaust system is damaged or leaking

Detection:

• CO may be present without the odor of exhaust gases
• Inexpensive, disposable detectors are in the aircraft

Stress

The body’s reaction to physical and psychological demands placed upon the body.

• How does this work?
• The body’s releases chemical hormones (such as adrenaline) into the blood and increasing metabolism to provide more energy to the muscles
• There are two types:
• Acute – immediate threat that is perceived as danger
• Chronic – presents and intolerable burden, exceeds the ability of an individual to cope, and causes a loss in performance

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Fatigue

The degradation of attention and concentration, impaired coordination, and decreased ability to communicate.

• What can cause fatigue?
• Lack of sleep, exercise, or physical work and things like stress and prolonged performance decrease mental fatigue

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Dehydration

• Dehydration: critical loss of water from the body
• Caused by hot flight decks, wind, humidity, and caffeinated drinks

Symptoms

• Headache
• Fatigue
• Cramps
• Sleepiness
• Dizziness

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To combat this, it is recommended to drink plenty of water the day prior

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Alcohol

• Alcohol consumption can cause performance deterioration and pilots must make hundreds of decisions in one flight
• The bloodstream absorbs about 80-90 percent of the alcohol in a drink within 30 minutes when ingested on an empty stomach
• It takes roughly 3 hours to get rid of the alcohol in your system from one drink and a considerable amount can last for 16 hours
• At altitude one drink could feel like 3 or 4
• Regulations regarding alcohol (91.17):
• Less than 0.04% and more than 8 hours must have passed between

Drugs

• 61.53 Prohibits acting as PIC or in any other capacity if that person
• knows or has reason to know of any medical condition that would not meet the medical certificate requirements
• Is taking medication or receiving other treatment for a medical condition that results in the person being unable to meet the medical certificate requirements
• 91.17 prohibits the use of any drug that affects the person and safety of the flight operation
• Approved over the counter medications can be found: Over the Counter Medications
• Proscribed and OTC medications that you cannot take before you fly can be found: Medications and Flying
• All others you must seek medical advice from an AME

Vision

• Your eyes are extremely important when it comes to flying
• There are two light-sensitive cells in your eyes: the cones and rods
• The cones are responsible for all color vision and are used to detect fine detail and color in high-light levels.
• The rods are very sensitive at low-light levels and in the dark are hard to adapt again once exposed to bring lighting. But the rods provide the majority of your night vision
• There are also three vision types
• Photopic Vision: responsible for seeing color and resolving fine detail
• Mesopic Vision: point at which your rods take on more vision responsibility
• Scotopic Vision: the cones are ineffective resulting in poor resolution and detail

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Altitude-Induced Decompression Sickness (DCS)

• DCS results from exposure to low barometric pressures that cause inert gases (mainly nitrogen), to form bubbles after rapid decompression.
• Also known as the bends

What should you do if this occurs?

• Put on an oxygen mask with 100% oxygen
• Begin and emergency descent and land as soon as possible
• If experiencing joint pain keep that area still
• Seek medical attention upon landing

Summary

• Aeronautical Decision Making (ADM) and Risk Management focus on making safe, informed choices and mitigating hazards.
• CRM/SRM emphasizes teamwork, communication, and resource use in crew and solo operations.
• Understanding Human Factors, situational awareness, and the decision-making process helps pilots maintain safety and adapt to changing conditions.
• Aeromedical and physiological issues like fatigue, stress, and altitude effects can impact pilot performance and must be managed proactively.

Quiz

1. Which of the following symptoms is commonly associated with hypoxia?

1. Increased alertness and improved focus
2. Euphoria and impaired judgment
3. Rapid and deep breathing with no other symptoms
4. Sudden onset of pain in the extremities

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2. What is the primary cause of hyperventilation in pilots?

1. Lack of oxygen at high altitudes
2. Excessive intake of carbon dioxide
3. Stress or anxiety leading to rapid breathing
4. Dehydration

3. Spatial disorientation occurs when:

1. The brain receives conflicting signals from the sensory systems
2. The body experiences a sudden change in altitude
3. Oxygen levels in the blood decrease dramatically
4. The visual horizon is clearly visible but the pilot is fatigued

4. Carbon monoxide poisoning is particularly dangerous for pilots because:

1. It is highly visible in the cockpit
2. Its symptoms mimic those of hypoxia
3. It only affects non-pressurized aircraft
4. It can be quickly corrected by breathing pure nitrogen

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5. What is the primary risk of flying after scuba diving without sufficient surface interval time?

1. Hyperventilation due to increased oxygen levels
2. Decompression sickness due to reduced atmospheric pressure
3. Carbon monoxide poisoning from the scuba equipment
4. Spatial disorientation from changes in water pressure