Human Factors AER100 PDF

HUMAN FACTORS AER100 – MICHAEL SARTOR To date, we have learned MANY technical aspects of flying What does HF mean? INTRODUCTION What does it include? Human – Environment – Machine Humans are terrestrial How can we adapt? crea...

HUMAN FACTORS AER100 – MICHAEL SARTOR To date, we have learned MANY technical aspects of flying What does HF mean? INTRODUCTION What does it include? Human – Environment – Machine Humans are terrestrial How can we adapt? creatures (boring!) AVIATION ACCIDENTS During WWII there were many aircraft accidents and loss of human life due to pilot incapacitation – not from combat Many accidents are preventable Often results from some strain of HF – 85% Disorientation, incapacitation, illusions, death AVIATION MEDICINE - 404 − MEDICAL REQUIREMENTS 404.03 Requirement to Hold 404.04 Issuance, Renewal and 404.06 Prohibition regarding a Medical Certificate (MC) Validity Period of MC Exercise of Privileges  Free of any condition that would alter: Alertness Decision making Reaction time GENERAL Certain medical conditions may prevent a HEALTH person from obtaining a medical Smaller issues such as acute infections temporarily disqualify a medical Can include any discomforts Colds, nausea, fatigue, indigestion, etc. PHYSICAL FACTORS  THE ATMOSPHERE Other Gases recall: 1% Std atmosphere is 1013.2mb Oxygen 21% Oxygen Partial Pressure: 21% Nitrogen 78% ie: of 1000mb (210mb) or 760mm (150mm) or 29.92”Hg (6.28”Hg) ATMOSPHERIC EFFECTS Decrease of Atmospheric Pressure Decrease of Partial Pressure Decrease of Total Pressure Hypoxia Trapped Gases Evolved Gases Abdominal, Decompression And Sinus, Sickness Dental Pains  HYPOXIA Tissues Modern technology allows us to operate at high O2 in, altitudes CO2 out Hypoxia is one of the most insidious physiological problems Difficult to detect in oneself Blood Hemoglobin Lack of sufficient oxygen in the body cells or Acts as tissues Lungs: Carrier Increased altitude = lack of oxygen (reduced partial CO2 Released pressure) which does not travel/absorb sufficiently O2 Absorbed throughout the body HYPOXIA Greatest concentration of air molecules at the earth’s surface Reduces with altitude At approx. 15,000’ there is half the amount of oxygen compared to sea level Remember it is difficult to detect in oneself The brain centre that warns you of this is affected first Results in the sense of well-being – no pain or discomfort Effects: euphoria, reduced vision, poor judgment, slow reaction time, eventual LOC and death  Hypoxic Hypoxia Histotoxic Hypoxia TYPES OF HYPOXIA Anemic Hypoxia Stagnant Hypoxia HYPOXIC HYPOXIA Normal effect of altitude Lack of oxygen in the tissue due to low partial pressure of oxygen at altitude Reduced oxygen in the lungs ATMOSPHERE COMPOSITION 10 0 % AND PROPERTIES 90% 80% Atmosphere has weight 70% 14.7 psi @ sea level or 1013.2 mb Half of it is below 18,000 feet 60% ¼ at 34,000’ 50% No well defined upper surface but 40% satellite drag data indicates some air at 1,000 miles Oxygen 21% 30% Gases each contribute to 20% Water/Other 1% atmospheric pressure – partial pressure of each gas 10 % Nitrogen 78% Water vapour usually less 0% than 1% but can be 3.5 %  OXYGEN DISSOCIATION CURVE WITH HAEMOGLOBIN Altitude X1000’ 10 8 6 4 S/L 100 % 90 Saturation 80 of blood 70 Hypoxic Range Cabin with O2 UNSAFE Altitude Range 60 50 40 30 20 10 0 10 20 30 40 50 60 70 80 90 100 110 120mm TIME OF USEFUL CONSCIOUSNESS Altitude Time 20,000 5-12 minutes 30,000 45-75 seconds 40,000 15-30 seconds 45,000 and above 12-15 seconds or less HYPOXIC HYPOXIA Normal Handwriting 10,000’ No Effect 15,000’ Muscular Incoordination 18,000’ Mental and Physical Inefficiency 20,000’ Aggravated Mental Incapacitation HYPOXIC HYPOXIA 22,000’ False Sense of Well-being 23,000’ Judgment, Insight and Coordination Lost 24,000’ Mental and Physical Helplessness 25,000’ Improvement with Supplementary Oxygen 30,000’ Some Improvement but not Completely Normal HISTOTOXIC HYPOXIA Chemical poisoning and high blood alcohol Amount of oxygen delivered to the tissue is sufficient Interference of the tissue’s ability to absorb delivered oxygen *Any kind of alcohol or drugs have no place in the flight deck*  Oxygen is transported by haemoglobin in the blood Carbon monoxide is 210 times more likely to bind with haemoglobin than is oxygen Lack of carrying capacity for blood to deliver oxygen to tissue CO is a colourless, odourless and tasteless gas ANEMIC a product of fuel combustion / can leak into the cabin if HYPOXIA there is a defect, crack or hole in the cabin heating system Other sources of CO are cabin fire or electrical fire Precautions ie. Walk around checks, journey log checks Susceptibility increases with altitude  Symptoms: Sluggish and warmness, headache, throbbing temples, ringing in the ears, dizziness, dimmed vision Eventually: vomiting, convulsions, coma and death if untreated CARBON Cigarette smoke contains a minute amount of carbon MONOXIDE monoxide POISONING A heavy smoker lowers their personal ceiling by 4000 feet or more (suffer from hypoxia) Smoking just 3 cigarettes at sea level will raise the physiological altitude to 8000  Immediately shut off the cabin heat system if you suspect CO poisoning Open all fresh source of air PROCEDURE TO Avoid smoking COUNTERACT Use 100% oxygen if available CO POISONING Land at the first opportunity and seek treatment (it may take several days for the CO to be completely expelled from the body) STAGNANT HYPOXIA Brain is deprived of adequate blood supply – high G maneuvers First symptom is reduced vision - loss of peripheral vision (Grey-Out) If the +G’s continue to increase - loss of all vision can result (black-out) As the +G’s continue to increase - loss of consciousness will result (G-LOC = G induced Loss of Consciousness) When negative G’s are encountered - blood pressure will increase causing Red-Out  HYPOXIA - EFFECTS ON VISION Retina is more dependent on an adequate supply of oxygen than any other part of the body First evidence of hypoxia will occur at 5000 feet at night with reduced night vision  Height at which pilots generally begin to become hypoxic is around 10,000 ft. HYPOXIA - AT Age, drinking habits, general fitness, 10,000 FEET fatigue and drug use will all have an impact on a persons susceptibility. Pilots fly up to 10,000 feet normally without any adverse affects of hypoxia.  Lassitude and indifference become appreciable HYPOXIA - AT Dimmed vision, tremors in the 14,000 FEET hands, clouding of thought and errors in judgment Cyanosis (blue discolouring of the fingernails) is first noticed  Pilot is belligerent or euphoric and is completely lacking in rational thought. HYPOXIA - AT 16,000 FEET Pilot becomes disoriented. Control of the aircraft can easily be lost.  Primary shock sets in. HYPOXIA - AT 18,000 FEET Pilot may lose consciousness within minutes. HYPOXIA - AT HIGH ALTITUDES Death may result after prolonged period of reduced oxygen Cabin pressure altitude? Use supplemental oxygen for flight above 10,000 feet during the day (5,000 feet at night) HYPOXIA RECOVERY Prevent the onset Use supplementary oxygen if legally required and when above 10,000’ during the day & 5,000’ by night Ensure fitness to fly Don’t exceed personal minimums for flying maneuvers Learn the signs and symptoms – you (even as a cool pilot) are not immune! HYPERVENTILATION Over breathing – usually anxiety or tension caused Deficiency of carbon monoxide in the blood Symptoms: Dizziness, tingling of fingers and toes, hot/cold sensations, nausea, sleepiness, LOC Recovery: Slow breathing rate, hold breath intermittently Similar to hypoxia – people tend to breath rapidly to prevent hypoxia, causing hyperventilation (this only decreases CO) If symptoms persist after slowing breathing rate + using oxygen, then treat for hyperventilation (consider altitude) DECOMPRESSION SICKNESS  Trapped gases in the body expand and contract (kinda like the altimeter) TRAPPED GASES Inability to expand Abdomen, and contact can teeth, sinuses, cause pain lungs Can lead to incapacitation  EARS Inner ear controls equilibrium senses + cochlea Air must be equalized in the Eustachian tube If air is trapped the ear drum can expand and cause pain and temp. deafness or rupture Mainly during descent as air has to be increased and the Eustachian tube does not open readily Sinus infections aggravate this issue Yawning, chewing gum, and the Valsalva technique assist May require to start a slow climb and complete a slower descent SEMICIRCULAR CANALS – VESTIBULAR ILLUSIONS Associated with equilibrium Filled with fluid and has tiny hairs that relate motion to the brain Must be an accelerated turn – contact velocity does not alter the sensations Motion of the fluid catches up to the canal walls and brain receives incorrect messages If turn is then stopped, brain sense a turn in the opposite direction Hair Cells SINUS, TEETH, GASTROINTESTINAL GASES Sinus: Difficult to equalize pressure if blocked – normally a cold Toothaches: Often a filled cavity, abscess, or root canal Gastrointestinal Pain: Expansion of gas within the digestive tract Common Cold: Tiredness, irritability, drowsiness, pain, and sinus issues all will increase with altitude Can result in vertigo or perforated eardrum EVOLVED GASES Nitrogen bubbles in the body are never good Results from decreased barometric pressure at altitude Can cause circulation issues, joint pain, and tissue damage Bends: pain around joints Chokes: chest pain due to bubbled in pulmonary blood vessels – must descend Creeps: tiny gas bubbles under the skin – tingling/itchy/cold/hot Best to have a pressurized cabin and/or breath 100% oxygen SCUBA DIVING Risk of decompression sickness at a much lower altitude than normal Body is supersaturated with nitrogen After non-decompression dives – avoid flights for 12 hours After decompression dives – avoid flights for 24 hours Rule of thumb – dives below 30ft, avoid flights for at least 24 hours VISION  Exposed to higher light levels while flying Atmosphere is less dense and lots of reflection with clouds Should wear sunglasses to protect eyes from harmful VISION blue and ultra-violet wavelengths Important to continue scan technique – empty field myopia Depth perception is often absent in the air NIGHT VISION Greatly impaired Cones require a lot of light to function properly Blind spots in the centre of the eye – have to use peripheral vision (15-20 deg) Rods take 30 min to fully adjust – small amounts of white light destroy adaptation Red light is best for the eyes – difficult with charts What altitude should supplementary oxygen be used? Thunderstorms can flash bright lights – make flight deck full bright Can turn off strobes & beacon to prevent flashing in cloud  Runway appears lower Rain showers on final approach can cause the lights to appear brighter and RAIN ON THE bigger WINDSHIELD Pilot reaction:You are too high Result: Pilot tends to undershoot the approach  Runway appears further away HAZE ON FINAL APPROACH Pilot tends to fly high on approach SLOPED RUNWAY Upslope Downslope Illusion that you are higher than you Illusion that you are lower than you actually are actually are Tendency to fly a low approach or Tendency to fly a high approach or undershoot overshoot RUNWAY WIDTH Narrow Runway Wide Runway Illusion that you are higher than you Illusion that you are lower than you actually are actually are Tendency to fly a low approach or Tendency to fly a high approach or undershoot overshoot, or flare too early SURROUNDING TERRAIN High Terrain Low Terrain Terrain around the runway is higher than Terrain around the runway is lower than the runway itself the runway itself Tendency to fly high and overshoot the Tendency to fly low and undershoot the approach approach TURNING ILLUSION Downwind to Into-Wind Into-Wind to Downwind Skidding sensation and decreased Slipping sensation and increased airspeed airspeed Typical response is to add too much Typical response is to add too much inside rudder inside rudder See an issue? See an issue? EMPTY FIELD MYOPIA Natural reaction of eye due to lack of stimulus Featureless sky Eye tends to focus 3-5ft away Objects appear smaller and further away What’s the risk? Can focus on wingtips to adjust vision SENSORY ILLUSIONS SPATIAL DISORIENTATION Loss of bearing or Rarely occurs with Flickering shadows – Can result in vertigo confusion relative to reduced vision propeller in the sun – rotating or spinning the surface CORIOLIS EFFECT Movement in 2 of the 3 semicircular canals The 3rd canal has a sympathetic but more violent movement Tumbling sensation or extreme nausea, confusion, rolling of the eyeballs Can occur when turning the aircraft, and then rapidly moving your head in another direction Avoid head movements in turns SOMATOGRAVIC – FALSE CLIMB ILLUSION Otolith – small organ in inner ear Senses and signals to other organs the position of head relative to vertical When exposed to acceleration – senses a pitch up movement Pilot is tempted to lower the nose and descend This increases forward acceleration and strengthens the illusion Loss of altitude can go unnoticed due to lag in instrumentation Occurs with take-off, overshoot/GA, climb (all with poor visibility) Deceleration has the opposite illusion – pilot pulls back and can lead to a stall BLACK HOLE ILLUSION Darkness without a visual cue On approach to land with dark terrain and limited features, you can overestimate altitude and fly too low, while viewing just the airport lights in the distance Brain tries to maintain constant angle between beginning and end of runway Results in curved path, and can land short of runway Options to avoid this? AUTOKINESIS Occurs when one focuses on a single light in an area where there is no other reference Featureless sky Minute involuntary eye motions cause the light to seemingly move in irregular arcs Static lights appear to move Can result in vertigo Focus eyes on objects in varying distances FALSE HORIZON Flying on a clear moonless night Lights below can blend with stars above the horizon Difficult to determine true horizon Can lead to spatial disorientation Can also occur with clouds How can we avoid this?  Minimum of 12 hours after a drink No alcohol in the system when you fly ALCOHOL & Effects increase with altitude DRUGS Over the counter medication is often not permitted Always consult your CAME before taking medication if you are flying BLOOD DONATION REFRAIN FROM TAKES SEVERAL WEEKS TO WAIT AT LEAST 48 HOURS VOLUNTEERING TO DONATE RETURN TO NORMAL BEFORE FLYING IF REGULARLY FLYING  General Anesthesia: Generally required for surgery Must by cleared by your doctors ANESTHESIA before returning to flying Local Anesthesia: For example, with some dental procedures Minimum 24 hours before flying OTHER CONSIDERATIONS Stress? Fatigue? Pregnancy – recall the requirements? Eating? Chronic and acute OTHER IRRITANTS Noise Vibration? Temperature?  Illness – any symptoms Medication – prescription or over-the-counter I.M.S.A.F.E. Stress – pressure, home, job, health CHECKLIST Alcohol – minimum 12 hours Fatigue – adequately rested Eating – adequately nourished HAZARDOUS ATTITUDES Anti-Authority: Don’t like being told what to do Resignation: “What’s the use!” People believe their actions/decisions will not make a difference Impulsivity: Do something, anything, immediately without consideration Invulnerability: “That won’t happen to me” You are more likely to take unwise risk Macho: “I can do it” Need to prove you are better than everyone else and take risk to prove/impress others  1. Be aware they exist and recognize them 2. Follow rules – they are usually right AVOIDING 3. Take time to think HAZARDOUS ATTITUDES 4. Realize you are not invincible 5. Don’t take unnecessary risk 6.Your decisions and actions make a difference  D – Detect change E – Estimate the E – Evaluate DECISION significance the progress of the change MAKING PROCESS “D.E.C.I.D.E” C – Choose D – Do the the outcome best action objective I – Identify plausible action options WORKLOAD MANAGEMENT Manage the load not to exceed your capacity CREW RESOURCE MANAGEMENT - CRM Most of your Airlines operate Increase Effectively using What are some flight training is multi-crew cooperation and all available types of CRM? “solo” or communication resources individually – you between crew are in charge! PERSONAL MINIMUMS We have already reviewed several TC regulations Weather minima, obstacle clearance, crosswinds etc. These are MINIMUMS Set personal minimums and adjust them as needed What are some examples? Tip: As you progress through training, write down these minimums – have it set in “stone.” Don’t let outside factors change your decision  Knowledge is power – and keeps us safe (and alive) Having a deep understanding of illusions and how to THE END… avoid/prevent them is critical ALMOST Don’t let your brain, eyes, and senses fool you Trust your instruments Remember you are not invincible  Congratulations on completing AER100 course content! THE END Final Words THANK YOU & FLY SAFE