Task H: Human Factors

Here's a detailed look at the knowledge (K1-K4) and risk management (R1-R4) elements for this task:

Knowledge (PA.I.H.K):

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PA.I.H.K1 Symptoms, recognition, causes, effects, and corrective actions associated with aeromedical and physiological issues:

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• a. Hypoxia: This is a state of oxygen deficiency in the body sufficient to impair brain and organ functions. Altitude hypoxia is caused by reduced barometric pressure, as the oxygen concentration in the atmosphere remains about 21%.

• Symptoms: Deterioration in night vision occurs at a cabin pressure altitude as low as 5,000 feet. Other significant effects usually start between 12,000 and 15,000 feet. Symptoms include impaired judgment, memory, alertness, coordination, and ability to make calculations. Headache, drowsiness, dizziness, and either euphoria or belligerence can also occur. As hypoxia worsens, vision may narrow, and instrument interpretation can become difficult. Despite these symptoms, hypoxia can give a pilot a false sense of security. Some sources list dizziness and euphoria as symptoms. Medications can make a pilot more susceptible to hypoxia.

• Effects: Impairs functions of the brain and other organs. Performance can seriously deteriorate within 15 minutes at 15,000 feet.

• Corrective Actions: Flying at lower altitudes and/or using supplemental oxygen. 

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• b. Hyperventilation: This is listed as an important medical factor.

• Symptoms: Dizziness and difficulty controlling breathing.

• Corrective Actions: Talking or having the person relax.

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• c. Middle ear and sinus problems: These are important medical factors.

• Symptoms: Pain in the ear or sinuses, especially during descent.

• Causes: Infection or mucus blocking sinuses, making it difficult to equalize pressure.

• Corrective Actions: Don't fly when sick.

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• d. Spatial disorientation: Orientation is awareness of the aircraft and oneself relative to a reference point; disorientation is a lack of this awareness, and spatial disorientation is specifically a lack of orientation in space and to other objects. It's listed as an important medical factor.

• Causes: Misleading information from the body's sensory organs (visual, vestibular, postural) when subjected to flight forces. Alcohol can make a pilot much more susceptible to disorientation. Basic instrument maneuvers training helps teach the susceptibility of the human system to spatial disorientation and demonstrates that judgments based on bodily sensations are often false.

• e. Motion sickness: Listed as an important medical factor. Some medications taken for motion sickness can have side effects that may impair critical functions like judgment, memory, alertness, coordination, vision, and calculation.

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• f. Carbon monoxide poisoning: Listed as an important medical factor.

• Symptoms: Cyanosis (bluing of fingernails and lips), dizziness, and euphoria.

• Corrective Actions: Decrease altitude and open a window to vent CO.

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• g. Stress: Listed as an important medical factor. Stress can impair the ability to make effective decisions during flight.

• Effects: Stress is cumulative. A certain amount of stress is beneficial (keeps a person alert and prevents complacency), but excessive levels can become an intolerable burden. Performance increases with stress up to a point, then falls off rapidly.

• Causes: Can be psychological (school/work, money, health, family/social life). Night flight can be more stressful.

• Corrective Actions: Stress management is discussed. Coping appropriately is necessary. IMSAFE checklist includes Stress. Knowing factors causing self-imposed stressors can help control stress during night flight.

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• h. Fatigue: Listed as an important medical factor. It is one of the most insidious hazards to flight safety, potentially not apparent until serious errors occur.

• Effects: Fatigue may cause pilots to be less discerning, less critical of information, less decisive, and more compliant and accepting. Performance may become a safety hazard depending on the degree of fatigue. Exhausted pilots tend to concentrate on one aspect instead of the whole situation, may fixate on instruments or stare. Fatigue can increase susceptibility to adverse effects from various drugs. If experiencing acute fatigue, stay on the ground. No amount of training or experience can overcome its detrimental effects.

• Causes: Not getting adequate rest, working excessive hours, or having an especially exhausting or stressful day. Late nights combined with the effects of sustained flight above 5,000 feet can contribute.

• Corrective Actions: Getting adequate rest is the only prevention. Avoid flying without a full night's rest, after excessive hours, or after an exhausting/stressful day. Pilots suspecting chronic fatigue should consult a physician. IMSAFE checklist includes Fatigue. The 5 P process can help pilots recognize physiological challenges like fatigue and plan accordingly.

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• i. Dehydration and nutrition: Dehydration is listed as an important medical factor. Dehydration and inadequate nutrition can increase a pilot's susceptibility to adverse effects from various drugs. The IMSAFE checklist includes "Eating" (Am I hungry?).

• (The provided sources do not offer specific symptoms, causes, effects, or corrective actions for dehydration and nutrition beyond their influence on drug susceptibility and general well-being.)

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• j. Hypothermia: Listed as a physiological issue.

• (The provided sources do not contain specific information on the symptoms, recognition, causes, effects, or corrective actions associated with hypothermia.)

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• k. Optical illusions: Listed as an important medical factor and an illusion in flight.

• Effects: Judgments of aircraft attitude based on bodily sensations are frequently false. Visual illusions at night are a specific consideration. Empty-field myopia is an illusion that occurs when flying above clouds or in haze, where the eyes relax and focus between 10 and 30 feet, resulting in "looking without seeing".

• Corrective Actions: Basic instrument maneuvers training helps decrease disorientation from illusions through better understanding of aircraft motion, head movements, and resulting disorientation. Searching out and focusing on distant light sources helps prevent empty-field myopia.

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• l. Dissolved nitrogen in the bloodstream after scuba dives: Listed as an important medical factor. This is also referred to as Decompression Sickness.

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PA.I.H.K2 Regulations regarding use of alcohol and drugs:

• Federal regulations prohibit pilots from performing crewmember duties while using any medication that affects their faculties contrary to safety.

• 14 CFR part 91, section 91.17 specifically prohibits using any drug that affects a person's faculties in any way contrary to safety.

• The safest rule is not to fly as a crewmember while taking any medication, unless approved by the FAA.

• Regarding alcohol, as little as one ounce of liquor, one bottle of beer, or four ounces of wine can impair flying skills. Alcohol consumed in these amounts is detectable in breath and blood for at least 3 hours. IMSAFE asks if you've been drinking within the previous 8 hours. The checkride discussion mentions needing at least eight hours after drinking before flying.

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PA.I.H.K3 Effects of alcohol, drugs, and over-the-counter medications:

• Alcohol: Can impair flying skills and renders a pilot much more susceptible to disorientation and hypoxia. A hangover can still cause severe impairment for many hours after alcohol is gone.

• Medications (Prescribed and OTC): Can seriously degrade pilot performance. Many medications (tranquilizers, sedatives, strong pain relievers, cough suppressants) have primary effects that may impair judgment, memory, alertness, coordination, vision, and the ability to make calculations. Others (antihistamines, blood pressure drugs, muscle relaxants, motion sickness agents) have side effects that may impair the same critical functions. Any medication that depresses the nervous system (like sedatives or antihistamines) can make a pilot more susceptible to hypoxia. Drugs that seem fine on the ground can cause problems at altitude due to changes in blood gases. Fatigue, stress, dehydration, and inadequate nutrition can increase susceptibility to adverse effects. Taking multiple medications can make adverse effects more pronounced. Drugs can seriously degrade visual acuity, especially at night. IMSAFE prompts pilots to consider if medications might affect judgment or cause drowsiness. For new medications, wait at least 48 hours before flying to check for adverse side effects.

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PA.I.H.K4 Aeronautical Decision-Making (ADM) to include using Crew Resource Management (CRM) or Single-Pilot Resource Management (SRM), as appropriate:

• Aeronautical Decision-Making (ADM): This is a systematic approach used by pilots to consistently determine the best course of action in aviation circumstances. It's what a pilot intends to do based on available information. ADM enhances the management of the aeronautical environment, and all pilots should use it. Poor decision-making is a significant factor in general aviation accidents. ADM is intended to break the "poor judgment chain" where one bad decision leads to another.

• Crew Resource Management (CRM) / Single-Pilot Resource Management (SRM): While CRM focuses on crew environments, many concepts apply to single-pilot operations. SRM is the application of CRM principles to single-pilot aircraft. SRM is the art and science of managing all resources available to a single pilot (on-board and outside) to ensure a successful flight outcome. SRM includes concepts like ADM, risk management (RM), task management (TM), automation management (AM), controlled flight into terrain (CFIT) awareness, and situational awareness (SA). SRM training helps pilots maintain situational awareness by managing automation, aircraft control, and navigation tasks, which enables accurate risk assessment and timely decisions. SRM is fundamentally about gathering information, analyzing it, and making decisions. It helps pilots identify problems, analyze information, and make informed, timely decisions. The IMSAFE and PAVE checklists are tools used within ADM/SRM. The "Five Ps" (the Plan, the Plane, the Pilot, the Passengers, and the Programming) is a practical application of SRM used to evaluate the pilot's situation at key decision points.

• Checklists: Checklists are explicitly mentioned as a human factors aid in aviation safety. They are systematic and sequential lists of operations. Proper use of checklists is evaluated throughout the practical test. This includes demonstrating CRM (or SRM for single-pilot), appropriately dividing attention, and using proper visual scanning. In situations where reading a checklist is unsafe or impractical (like immediate actions), the applicant should use memory items and review the checklist later when conditions permit. For a single-pilot airplane, SRM principles should be demonstrated.

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Risk Management (PA.I.H.R):

• PA.I.H.R1 Aeromedical and physiological issues: You must be able to identify, assess, and mitigate risks associated with the aeromedical and physiological conditions listed in K1. This involves understanding the symptoms and effects and taking appropriate corrective action or deciding not to fly if unfit. The IMSAFE checklist is a specific tool for performing a self-assessment of your fitness for flight based on Illness, Medication, Stress, Alcohol, Fatigue, and Emotion.

• PA.I.H.R2 Hazardous attitudes: You must be able to identify, assess, and mitigate risks associated with hazardous attitudes. ADM includes identifying personal attitudes hazardous to safe flight and learning behavior modification techniques. (The sources do not explicitly list or define specific hazardous attitudes for the private pilot level in the provided text.)

• PA.I.H.R3 Distractions, task prioritization, loss of situational awareness, or disorientation: These are significant risk areas. Task management involves effectively managing information workloads and automated systems to reduce workload during critical flight phases and prevent overload/stress. Pilots have limited capacity, and distractions and fixation hinder information processing. Fixating on a less important issue (like an instrument light failure) can prevent appreciation of more critical tasks. Situational awareness (SA) is the accurate perception and understanding of factors affecting the flight, including the aircraft, environment, and pilot. It's being aware of what is happening in and around the flight. SRM training helps pilots maintain SA. Good judgment during landing involves dividing attention and scanning. Off-center viewing and scanning maximize SA at night.

• PA.I.H.R4 Confirmation and expectation bias: This is listed as a risk management area. (The provided sources do not explicitly define or discuss confirmation bias or expectation bias.)

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What you should know to pass your private pilot exam:

Based on the ACS, to demonstrate satisfactory understanding and pass the exam regarding Human Factors, you need to:

1. Understand the common aeromedical and physiological issues that can affect a pilot, specifically Hypoxia, Hyperventilation, Middle ear and sinus problems, Spatial disorientation, Motion sickness, Carbon monoxide poisoning, Stress, Fatigue, Dehydration/nutrition, Hypothermia, Optical illusions, and Dissolved nitrogen after scuba diving (decompression sickness). For at least three of these conditions, you must be able to associate the symptoms and effects with their cause(s) and corrective action(s).

2. Know the regulations regarding alcohol and drug use by pilots. Understand the minimum time required after consuming alcohol before flying.

3. Understand the effects that alcohol, drugs, and over-the-counter medications can have on a pilot's ability to safely operate an aircraft, including impairment of judgment, coordination, vision, and increased susceptibility to conditions like hypoxia. Know the recommendation to wait at least 48 hours after starting a new medication before flying.

4. Understand Aeronautical Decision-Making (ADM) and Single-Pilot Resource Management (SRM) (or CRM if applicable). Be familiar with tools like the IMSAFE checklist for pilot self-assessment and potentially the PAVE checklist for overall risk assessment (Pilot, Aircraft, enVironment, External pressures). Recognize that ADM/SRM involves gathering information, analyzing it, and making decisions.

5. Be able to perform a self-assessment of your fitness for flight, considering personal minimums, based on the actual flight conditions or a scenario provided by the evaluator.

6. Understand and apply risk management principles related to aeromedical issues, hazardous attitudes, distractions, task prioritization, loss of situational awareness, and disorientation.

7. Demonstrate appropriate use of checklists during flight, including using memory items for immediate actions and reviewing the checklist when practical and safe.

8. Understand the difference between proficiency and currency. You need to be both legal (current) and competent (proficient). Personal minimums are part of defining your proficiency.

This task emphasizes that being a safe pilot involves more than just operating the controls; it requires understanding your own physical and mental state and how human limitations can affect safety.

 

**I'm not a CFI, don't forget to verify the information as times change. Email me for any updates that I might have missed.