1、Human Factors The elements affecting human interaction with other people, machines, and the environment they encounter,Elements covered in this chapter,Sensory Systems for orientation Illusions in flight Physiological and psychological factors Medical factors Aeronautical decision making (ADM) Crew
2、Resource management (CRM) and Single Pilot Resource Management (SRM),Sensory Systems for Orientation,Eyes - maintain visual orientation Ears motion sensing maintains vestibular orientation Nerves located throughout the body in the skin, joints, and muscles to maintain postural orientation When confl
3、icting information comes from these 3 systems we become disoriented,Vision,We obtain most of our orientation through our vision The majority of visual orientation is good but there are some flaws especially when we do not have adequate reference points Flaws are: Blind spots Night vision limitations
4、 Visual illusions (false horizon, autokinesis) Optical illusions,Components of the eye,Rods,Used during low levels of light, (scotopic vision) Found along the retina; used for peripheral vision. Not effective for detecting color or detail. Produce rhodopsin using oxygen. Rhodopsin bleaches quickly i
5、f exposed to light There are approximately 20 to 30 times more rods than cones,Cones,Concentrated at the fovea They are useful for detecting color, fine detail, and during high illumination, (photopic vision) When exposed to low levels of illumination, cones produce iodopsin. Iodopsin makes the cone
6、s 100X more sensitive to light,Blind SPots,Scan techniques,As you scan, do not scan more than 10 degrees at time. Focus on the area for at least 1 second and allow 1 second for your eyes to focus on the new location. For night operations, use off center/peripherals in order to utilize rods At night
7、dont focus on an object as it will fade due to autokinesis Scanning continuously to expose new areas of the retina to the light. Develop your scan,Preparing for Night flight,Avoid bright white light for 30 minutes Preflight using a dim light If you are exposed to a bright light, close one eye to avo
8、id ruining night vision in both eyes Avoid using red lights, as red on the charts will not show up.,Visual Illusions,False Horizon A sloping cloud formation, an obscured horizon, an aurora borealis, a dark scene spread with ground lights and stars, and certain geometric patterns of ground lights can
9、 provide inaccurate visual information, or false horizon, for aligning the aircraft correctly with the actual horizon. The disoriented pilot may place the aircraft in a dangerous attitude. Autokinesis In the dark, a stationary light will appear to move about when stared at for many seconds. The diso
10、riented pilot could lose control of the aircraft in attempting to align it with the false movements of this light, called autokinesis.,Optical Illusions,Optical Illusions,Optical Illusions,Runway Width illusion Runway and Terrain Slopes Illusion Featureless Terrain Illusion Water Refraction Haze Fog
11、 Ground Lighting Illusions,Preventing landing errors,Anticipate possible illusions, particularly at night or adverse weather conditions Make frequent references to the altimeter If possible, fly over airport for visual inspection Use VASI or a PAPI Utilize visual decent point (VDP) found on non prec
12、ision instrument approach procedure charts Maintain landing proficiency,Ears,Illusions leading to Spatial Disorientation,Besides the visual illusions caused by the human eye sight. The sensory system responsible for most of the illusions leading to spatial disorientation is the vestibular system. Ve
13、stibular Illusions The Leans Coriolis Illusion Graveyard Spiral Somatogravic Illusion Inversioin Illusion Elevator Illusion,The leans,when a banked attitude, to the left for example, may be entered too slowly to set in motion the fluid in the “roll” semicircular tubes. An abrupt correction of this a
14、ttitude sets the fluid in motion, creating the illusion of a banked attitude to the right. The disoriented pilot may make the error of rolling the aircraft into the original left banked attitude, or if level flight is maintained, will feel compelled to lean in the perceived vertical plane until this
15、 illusion subsides.,Coriolis Illusion,when a pilot has been in a turn long enough for the fluid in the ear canal to move at the same speed as the canal. A movement of the head in a different plane, such as looking at something in a different part of the flight deck, may set the fluid moving and crea
16、te the illusion of turning or accelerating on an entirely different axis.,Graveyard Spiral,A pilot in a prolonged coordinated, constant-rate turn will have the illusion of not turning. During the recovery to level flight, the pilot will experience the sensation of turning in the opposite direction,S
17、omatogravic Illusion,A rapid acceleration, such as experienced during takeoff, stimulates the otolith organs in the same way as tilting the head backwards. This action creates the somatogravic illusion of being in a nose-up attitude,Inversion and Elevator Illusion,Inversion Illusion - An abrupt chan
18、ge from climb to straight-and-level flight can stimulate the otolith organs enough to create the illusion of tumbling backwards. Elevator Illusion - An abrupt upward vertical acceleration, as can occur in an updraft, can stimulate the otolith organs to create the illusion of being in a climb.,Preven
19、tion of Illusions,Obtain a weather briefing. Stay proficient! Avoid rapid head movements during flight. Do not fly when you are ill. Do not continue into deteriorating conditions unless proficient. ALWAYS TRUST YOUR INSTRUMENTS!,Postural Considerations,The postural system sends signals from the skin
20、, joints, and muscles to the brain that are interpreted in relation to the Earths gravitational pull. These signals determine posture. Inputs from each movement update the bodys position to the brain on a constant basis.,aeroMedical Factors,Medical Standards Hypoxia Middle ear and sinus block Dehydr
21、ation and heatstroke Motion sickness Hyperventilation Decompression sickness Supplemental oxygen,Carbon Monoxide Poisoning Illness Medication Stress Alcohol Fatigue Emotion,Medical Certificate Standards,Medical Certificate Requirements and Duration 61.23 Under 40: First class 12 months, Second class
22、 12 months, Third class 60 months Over 40: First class 6 months, Second class 12 months, Third class 24 months Standards for medical certification are contained in Title 14 of the Code of Federal Regulations (14 CFR) part 67 and the requirements for obtaining medical certificates can be found in 14
23、CFR parts 61 As a commercial pilot: Third class medical the minimum required for check ride Second class medical is the minimum required for commercial operators to work for hire, with exception of flight instruction. First class medical is required for airline operators.,Hypoxia,Means “reduced oxyg
24、en” or “not enough oxygen” Largest concern is oxygen deprivation to the brain because of how vulnerable it is to oxygen deficiency Hypoxia can be caused by several factors, including an insufficient supply of oxygen, inadequate transportation of oxygen, or the inability of the body tissues to use ox
25、ygen. Four forms of hypoxia according to their causes.,Hypoxia,Symptoms of Hypoxia- the first symptoms are euphoria and a carefree feeling. Cyanosis (blue fingernails and lips) Headache Decreased reaction time Impaired judgment Euphoria Visual impairment (narrows) Drowsiness Tingling in fingers and
26、toes Numbness Lightheaded or dizzy sensation,Hypoxia,Hypoxic Hypoxic hypoxia is a result of inadequate supply of oxygen to the body as a whole. Possible causes: Reduction in partial pressure of oxygen at high altitude. (same % of oxygen but less molecules) Corrective action: use aviation oxygen, des
27、cend altitude Hypemic Hypemic means “inability of the blood to carry oxygen.” Hemoglobin chemically unable to bind with oxygen causes: anemia, disease, blood loss, deformed blood cells, carbon monoxide poisoning, smoking corrective action: use aviation oxygen, exercise, decrease altitude, cabin heat
28、 off & vents open, land as soon as possible,Hypoxia,Stagnant Stagnant means “inadequate circulation of oxygen,” and stagnant hypoxia, or ischemia, from shock, the heart failing to pump blood effectively, or a constricted artery. Causes: excessive G-loads, cold temperatures Corrective action: exercis
29、e, use aviation oxygen, decrease altitude, stop Gs Histotoxic The inability of cells to effectively make use of oxygen Causes: alcohol or narcotics, and poisoning (1oz of alcohol=2000feet) Corrective action: use aviation oxygen, dont do drugs,Hypoxia,Time of Useful consciousness Altitude (MSL) Time
30、of useful consciousness (sec) 45,000 ft. 9-15 40,000 ft. 15-20 35,000 ft. 30-60 30,000 ft. 60-120 28,000 ft. 150-180 25,000 ft. 180-300 22,000 ft. 5-10 minutes 20,000 ft. 30 minutes or more,Middle Ear and Sinus Block,During climbs and descents, the free gas formerly present in various body cavities
31、expands due to a difference between the pressure of the air outside the body and that of the air inside the body. This causes ear pain and sinus pain, as well as a temporary reduction in the ability to hear. The Eustachian tube which connects the middle ear to outside pressure can be opened through
32、Chewing, yawning, and swallowing. Pinch the nostrils shut, close the mouth and lips, and blow slowly and gently in the mouth and nose. Can use nasal sprays but first check with AME. Respiratory infections such as colds or sinusitis or nasal allergies can produce enough congestion to slow the equaliz
33、ation. Symptoms Slow descent rates associated with pain above each eyebrow or upper cheeks Teeth aches Corrective action Avoid flying with upper respiratory infections,Dehydration and Heatstroke,Critical loss of water from the body. Heatstroke is a condition caused by any inability of the body to co
34、ntrol its temperature. Causes Hot flight decks and flight lines Wind Humidity Diuretic drinks: coffee, tea, alcohol, caffeinated soft drinks Signs and Symptoms Headache Fatigue Cramps Drowsiness Dizziness Prevention Drink 2 to 4 quarts of water daily Limit daily intake of caffeine and alcohol,Motion
35、 Sickness,Caused most of the time by vestibular disorientation (brain receiving conflicting messages about the state of the body. Symptoms Nausea General discomfort paleness Vomiting Sweating Dizziness To overcome motion sickness Focusing eyes on a specific point outside of the aircraft, when in IFR
36、 conditions has patient focus on the instrument panel. Avoid unnecessary head movements. Fresh air. Keep the aircraft coordinated and fly straight and level.,Hyperventilation,Excessive rate and depth of respiration leading to abnormal loss of carbon dioxide from the blood. The respiratory systems at
37、tempts an overriding mechanism to regain control of breathing. If using supplemental oxygen, check the equipment and flow rate to ensure the symptoms are not hypoxia related. Symptoms Rapid breathing rate Hypoxia Drowsiness Dizziness Shortness of breath Feeling of suffocation Visual impairment Uncon
38、sciousness Tingling sensations Hot and cold sensations Muscle spasms,Hyperventilation,Triggered through Fear Anxiety Tension Corrective action Slow breathing rate Talking aloud (have patient sing a song) Breath into a paper bag,Decompression Sickness,Decompression sickness (DCS) - variety of symptom
39、s resulting from exposure to low barometric pressures that cause inert gases (mainly nitrogen), normally dissolved in body fluids and tissues, to come out of physical solution and form bubbles. On the surface nitrogen can build in the blood stream. As altitude increases the nitrogen will expand and
40、cause severe joint pain. SCUBA AIM 8-1-2 d.2. “the recommended waiting time before going to flight altitudes up to 8,000 ft is at least 12 hours after diving which has not required a controlled ascent (non-decompression stop diving), and at least 24 hours after diving which has required a controlled
41、 ascent (decompression stop diving). The recommended time before going to flight altitudes above 8,000 ft should be at least 24 hours after any SCUBA dive.”,Decompression sickness,What to do when altitude-induced DCS occurs: Put on oxygen mask immediately and switch the regulator to 100 percent oxyg
42、en. Begin an emergency descent and land as soon as possible. Even if the symptoms disappear during descent, land and seek medical evaluation while continuing to breathe oxygen If one of the symptoms is joint pain, keep the affected area still; do not try to work pain out by moving the joint around.
43、Upon landing seek medical assistance from an FAA medical officer, AME, military flight surgeon, or a hyperbaric medicine specialist. Be aware that a physician not specialized in aviation or hypobaric medicine may not be familiar with this type of medical problem. Definitive medical treatment may inv
44、olve the use of a hyperbaric chamber operated by specially trained personnel. Delayed signs and symptoms of altitude-induced DCS can occur after return to ground level regardless of presence during flight.,Supplemental Oxygen,91.211 Supplemental oxygen no person may operate a civil aircraft of U.S.
45、registry - At altitudes above 12,500 MSL up to an including 14,000 ft unless the minimum required flight crew is provided with supplemental oxygen after flights at altitudes in excess of 30 minutes - At cabin pressure altitudes above 14,000 ft MSL unless the minimum required flight crew is provided
46、with supplemental oxygen for the duration of the flight - At cabin pressure altitudes above 15,000 ft MSL unless each occupant is provided with supplemental oxygen for the duration of the flight Pressurized aircraft - At Flight altitudes above FL 250 unless there is a 10 minutes supply of oxygen - A
47、t flight altitudes above FL 350 when there is one pilot at the controls of the aircraft he/she has to be using supplemental oxygen - At or above FL 410 each pilot has to have a quick donning mask within a 5 second reach,Supplemental Oxygen Equipment,Oxygen systems Diluter demand a quick donning mask
48、 which mixes cabin air with oxygen and changes the ratio based upon altitude Pressure demand only provides oxygen when inhaling Continuous flow constant or adjustable flow compensated for altitude which is adjusted by a barometric pressure valve High pressure oxygen bottles Must be 99.5% pure oxygen
49、 Not more than .005 Milligrams of water per liter Pressure should be kept above 50 psi to ensure moisture stays out Storage must be kept secure, and clean,Carbon Monoxide (CO) Poisoning,- A colorless and odorless gas produced by all internal combustion engines. Attaching itself to the hemoglobin in
50、the blood about 200 times more easily than oxygen, CO prevents the hemoglobin from carrying oxygen to the cells, resulting in hypemic hypoxia. The body requires up to 48 hours to dispose of CO. Syptoms include: headache, blurred vision, dizziness, drowsiness, and/or loss of muscle power. Actions should be: Turn off the heater, opening fresh air vents and windows, and use supplemental oxygen, if available. CO detectors are useful. CO from Smoking will cause the body to feel as it were at 8000.,
