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发表于 2009-3-21 00:07:21
light. The pattern of light that strikes the cones and rodsis transmitted as electrical impulses by the optic nerveto the brain where these signals are interpreted as animage. The area where the optic nerve meets the retinacontains no cones or rods, creating a blind spot invision. Normally, each eye compensates for the other’sblind spot. CONESCones are concentrated around the center of theretina. They gradually diminish in number as the distance from the center increases. Cones allow you toperceive color by sensing red, blue, and green light.Directly behind the lens, on the retina, is a small,notched area called the fovea. This area contains onlya high concentration of cone receptors. When youlook directly at an object, the image is focusedmainly on the fovea. The cones, however, do notThe rods and cones (film) of the retinaare the receptors, which record theimage and transmit it through the opticnerve to the brain for interpretation.Light passesthrough the cornea(the transparent window onthe front of the eye) and then throughthe lens to focus on the retina.The pupil (aperture) is theopening at the center ofthe iris. The size of thepupil is adjusted tocontrol the amountof light enteringthe eye.LensIrisPupilCorneaOptic NerveRetinaRods andConesFovea(All Cones)RodConcentration{{{{{Figure 13-1. A camera is able to focus on near and far objectsby changing the distance between the lens and the film. Youcan see objects clearly at various distances because theshape of your eye’s lens is changed automatically by smallmuscles.Figure 13-2. This illustration provides a dramatic example ofthe eye’s blind spot. Cover your right eye and hold this pageat arm’s length. Focus your left eye on the X in the right sideof the visual, and notice what happens to the aircraft as youslowly bring the page closer to your eye.13-2function well in darkness, which explains why youcannot see color as vividly at night as you can duringthe day. RODSThe rods are our dim light and night receptors and areconcentrated outside the fovea area. The number ofrods increases as the distance from the fovea increases.Rods sense images only in black and white. Becausethe rods are not located directly behind the pupil, theyare responsible for much of our peripheral vision.Images that move are perceived more easily by the rodareas than by the cones in the fovea. If you have everseen something move out of the corner of your eye, itwas most likely detected by your rod receptors.Since the cones do not function well in the dark, youmay not be able to see an object if you look directly atit. The concentration of cones in the fovea can make anight blindspot at the center of your vision. To see anobject clearly, you must expose the rods to the image.This is accomplished by looking 5° to 10° off center ofthe object you want to see. You can try out this effecton a dim light in a darkened room. When you lookdirectly at the light, it dims or disappears altogether. Ifyou look slightly off center, it becomes clearer andbrighter. How well you see at night is determined by the rods inyour eyes, as well as the amount of light allowed intoyour eyes. The wider the pupil is open at night, the better your night vision becomes.NIGHT VISIONThe cones in your eyes adapt quite rapidly to changes inlight intensities, but the rods do not. If you have everwalked from bright sunlight into a dark movie theater, youhave experienced this dark adaptation period. The rodscan take approximately 30 minutes to fully adapt to thedark. Abright light, however, can completely destroy yournight adaptation and severely restrict your visual acuity.There are several things you can do to keep your eyesadapted to the dark. The first is obvious; avoid brightlights before and during the flight. For 30 minutesbefore a night flight, avoid any bright light sources,such as headlights, landing lights, strobe lights, orflashlights. If you encounter a bright light, close oneeye to keep it light sensitive. This allows you to seeagain once the light is gone. Light sensitivity also canbe gained by using sunglasses if you will be flying fromdaylight into an area of increasing darkness.Red cockpit lighting also helps preserve your nightvision, but red light severely distorts some colors, andcompletely washes out the color red. This makes reading an aeronautical chart difficult. A dim white
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light orcarefully directed flashlight can enhance your nightreading ability. While flying at night, keep the instrument panel and interior lights turned up no higher thannecessary. This helps you see outside visual referencesmore easily. If your eyes become blurry, blinking morefrequently often helps.Your diet and general physical health have an impacton how well you can see in the dark. Deficiencies invitamins A and C have been shown to reduce night acuity. Other factors, such as carbon monoxide poisoning,smoking, alcohol, certain drugs, and a lack of oxygenalso can greatly decrease your night vision.NIGHT SCANNINGGood night visual acuity is needed for collision avoidance. Night scanning, like day scanning, uses a seriesof short, regularly spaced eye movements in 10° sectors. Unlike day scanning, however, off-center viewingis used to focus objects on the rods rather than the foveablindspot. When you look at an object, avoid staring atit too long. If you stare at an object without movingyour eyes, the retina becomes accustomed to the lightintensity and the image begins to fade. To keep itclearly visible, new areas in the retina must be exposedto the image. Small, circular eye movements helpeliminate the fading. You also need to move your eyesmore slowly from sector to sector than during the dayto prevent blurring.Focus onFoveaCones ActiveNight BlindspotRods ActiveFigure 13-3. The best vision in daylight is obtained by looking directly at the object. This focuses the image on thefovea, where detail is best seen.Figure 13-4. In low light, the cones lose much of their visualacuity, while rods become more receptive. The eye sacrificessharpness for sensitivity. Your ability to see an object directlyin front of you is reduced, and you lose much of your depthperception, as well as your judgment of size.13-3AIRCRAFT LIGHTINGIn order to see other aircraft more clearly, regulationsrequire that all aircraft operating during the night hourshave special lights and equipment. The requirementsfor operating at night are found in Title 14 of the Codeof Federal Regulations (14 CFR) part 91. In addition toaircraft lighting, the regulations also provide a definition of nighttime, currency requirements, fuel reserves,and necessary electrical systems.Position lights enable you to locate another aircraft, aswell as help you determine its direction of flight. Theapproved aircraft lights for night operations are a greenlight on the right cabin side or wingtip, a red light onthe left cabin side or wingtip, and a white position lighton the tail. In addition, flashing aviation red or white
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anticollision lights are required for night flights. Theseflashing lights can be in a number of locations, but aremost commonly found on the top and bottom of thecabin. VISUAL ILLUSIONSThere are many different types of visual illusions thatyou can experience at any time, day or night. The nextfew paragraphs cover some of the illusions that commonly occur at night.AUTOKINESISAutokinesis is caused by staring at a single point oflight against a dark background, such as a ground lightor bright star, for more than a few seconds. After a fewmoments, the light appears to move on its own. To prevent this illusion, you should focus your eyes onobjects at varying distances and not fixate on one target, as well as maintain a normal scan pattern.NIGHT MYOPIAAnother problem associated with night flying is nightmyopia, or night-induced nearsightedness. With nothing to focus on, your eyes automatically focus on apoint just slightly ahead of your aircraft. Searching outand focusing on distant light sources, no matter howdim, helps prevent the onset of night myopia.FALSE HORIZONA false horizon can occur when the natural horizon isobscured or not readily apparent. It can be generated byconfusing bright stars and city lights. Itcan also occur while you are flying toward the shore ofan ocean or a large lake. Because of the relative darknessof the water, the lights along the shoreline can be mistaken for the stars in the sky. WhiteRedGreenYour HelicopterWhiteGreenRedRed GreenWhiteFigure 13-5. By interpreting the position lights on other aircraft, you can determine whether the aircraft is flying away from youor is on a collision course. If you see a red position light to the right of a green light, such as shown by aircraft number 1, it isflying toward you. You should watch this aircraft closely and be ready to change course. Aircraft number 2, on the other hand,is flying away from you, as indicated by the white position light.Apparent HorizonActualHorizonApparent HorizonActual HorizonFigure 13-6. You can place your helicopter in an extremelydangerous flight attitude if you align the helicopter with thewrong lights. Here, the helicopter is aligned with a road andnot the horizon.Figure 13-7. In this illusion, the shoreline is mistaken for thehorizon. In an attempt to correct for the apparent nose-highattitude, a pilot may lower the collective and attempt to fly“beneath the 獨潲攮13-4LANDING ILLUSIONSLanding illusions occur in many forms. Above featureless terrain at night, there is a natural tendency to fly alower-than-normal approach. Elements that cause anytype of visual obscuration, such as rain, haze, or a darkrunway environment also can cause low approaches.Bright lights, steep surrounding terrain, and a wide runway can produce the illusion of being too low, with atendency to fly a higher-than-normal approach.NIGHT FLIGHTThe night flying environment and the techniques you usewhen flying at night, depend on outside conditions.Flying on a bright, clear, moonlit evening when the visibility is good and the wind is calm, is not much differentfrom flying during the day. However, if you are flyingon an overcast night over a sparsely populated area,with little or no outside lights from the ground, the situation is quite different. Visibility is restricted so youhave to be more alert in steering clear of obstructionsand low clouds. Your options are also limited in theevent of an emergency, as it is more difficult to finda place to land and determine wind direction andspeed. At night, you have to rely more heavily on theaircraft systems, such as lights, flight instruments, andnavigation equipment. As a precaution, if the visibilityis limited or outside references are inadequate, youshould strongly consider delaying the flight until conditions improve, unless you have received training ininstrument flight and your helicopter has the appropriate instrumentation and equipment.PREFLIGHTThe preflight inspection is performed in the usual manner, except it should be done in a well lit area or with aflashlight. Careful attention must be paid to the aircraftelectrical system. In helicopters equipped with fuses, aspare set is required by regulation, and common sense,so make sure they are onboard. If the helicopter isequipped with circuit breakers, check to see that theyare not tripped. A tripped circuit breaker may be anindication of an equipment malfunction. Reset it andcheck the associated equipment for proper operation.Check all the interior lights, especially the instrumentand panel lights. The panel lighting can usually be controlled with a rheostat or dimmer switch, allowing youto adjust the intensity. If the lights are too bright, a glaremay reflect off the windshield creating a distraction.Always carry a flashlight with fresh batteries to provide an alternate source of light if the interior lightsmalfunction.All aircraft operating between sunset and sunrise arerequired to have operable navigation lights. Turnthese lights on during the preflight to inspect themvisually for proper operation. Between sunset andsunrise, theses lights must be on any time the engineis running.All recently manufactured aircraft certified for nightflight, must have an anticollision light that makes theaircraft more visible to other pilots. This light is eithera red or white flashing light and may be in the form of
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a rotating beacon or a strobe. While anticollision lightsare required for night VFR flights, they may be turnedoff any time they create a distraction for the pilot.One of the first steps in preparation for night flight isbecoming thoroughly familiar with the helicopter’scockpit, instrumentation and control layout. It is recommended that you practice locating each instrument,control, and switch, both with and without cabin lights.Since the markings on some switches and circuitbreaker panels may be hard to read at night, you shouldassure yourself that you are able to locate and use thesedevices, and read the markings in poor light conditions.Before you start the engine, make sure all necessaryequipment and supplies needed for the flight, such ascharts, notepads, and flashlights, are accessible andready for use.ENGINE STARTING AND ROTORENGAGEMENTUse extra caution when starting the engine and engaging the rotors, especially in dark areas with little or nooutside lights. In addition to the usual call of “clear,”turn on the position and anticollision lights. If conditions permit, you might also want to turn the landinglight on momentarily to help warn others that you areabout to start the engine and engage the rotors.TAXI TECHNIQUELanding lights usually cast a beam that is narrow andconcentrated ahead of the helicopter, so illumination tothe side is minimal. Therefore, you should slow yourtaxi at night, especially in congested ramp and parkingareas. Some helicopters have a hover light in additionto a landing light, which illuminates a larger area underthe helicopter.When operating at an unfamiliar airport at night, youshould ask for instructions or advice concerning localconditions, so as to avoid taxiing into areas of construction, or unlighted, unmarked obstructions. Groundcontrollers or UNICOM operators are usually cooperative in furnishing you with this type of information.TAKEOFFBefore takeoff, make sure that you have a clear, unobstructed takeoff path. At airports, you may accomplishthis by taking off over a runway or taxiway, however, if13-5you are operating off-airport, you must pay more attention to the surroundings. Obstructions may also be difficult to see if you are taking off from an unlighted area.Once you have chosen a suitable takeoff path, select apoint down the takeoff path to use for directional reference. During a night takeoff, you may notice a lack ofreliable outside visual references after you are airborne.This is particularly true at small airports and off-airportlanding sites located in sparsely populated areas. Tocompensate for the lack of outside references, use theavailable flight instruments as an aid. Check the altimeter and the airspeed indicator to verify the proper climbattitude. An attitude indicator, if installed, can enhanceyour attitude reference.The first 500 feet of altitude after takeoff is consideredto be the most critical period in transitioning from thecomparatively well-lighted airport or heliport intowhat sometimes appears to be total darkness. A takeoffat night is usually an “altitude over airspeed” maneuver, meaning you will most likely perform a nearlymaximum performance takeoff. This improves thechances for obstacle clearance and enhances safety.When performing this maneuver, be sure to avoid thecross-hatched or shaded areas of the height-velocitydiagram.EN ROUTE PROCEDURESIn order to provide a higher margin of safety, it is recommended that you select a cruising altitude somewhathigher than normal. There are several reasons for this.First, a higher altitude gives you more clearancebetween obstacles, especially those that are difficult tosee at night, such as high tension wires and unlightedtowers. Secondly, in the event of an engine failure, youhave more time to set up for a landing and the glidingdistance is greater giving you more options in making asafe landing. Thirdly, radio reception is improved, particularly if you are using radio aids for navigation.During your preflight planning, it is recommended thatyou select a route of flight that keeps you within reachof an airport, or any safe landing site, as much of thetime as possible. It is also recommended that you fly asclose as possible to a populated or lighted area such asa highway or town. Not only does this offer moreoptions in the event of an emergency, but also makesnavigation a lot easier. A course comprised of a seriesof slight zig-zags to stay close to suitable landing sitesand well lighted areas, only adds a little more time anddistance to an otherwise straight course.In the event that you have to make a forced landing atnight, use the same procedure recommended for day-time emergency landings. If available, turn on the landing light during the final descent to help in avoidingobstacles along your approach path.COLLISION AVOIDANCE AT NIGHTAt night, the outside visual references are greatlyreduced especially when flying over a sparsely populated area with little or no lights. The result is that youtend to focus on a single point or instrument, makingyou less aware of the other traffic around. You mustmake a special effort to devote enough time to scan fortraffic. You can determine another aircraft’s directionof flight by interpreting the position and anticollisionlights.
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APPROACH AND LANDINGNight approaches and landings do have some advantages over daytime approaches, as the air is generallysmoother and the disruptive effects of turbulence andexcessive crosswinds are often absent. However, thereare a few special considerations and techniques thatapply to approaches at night. For example, when landing at night, especially at an unfamiliar airport, makethe approach to a lighted runway and then use the taxiways to avoid unlighted obstructions or equipment.Carefully controlled studies have revealed that pilotshave a tendency to make lower approaches at nightthan during the day. This is potentially dangerous asyou have a greater chance of hitting an obstacle, suchas an overhead wire or fence, which are difficult to see.It is good practice to make steeper approaches at night,thus increasing any obstacle clearance. Monitor youraltitude and rate of descent using the altimeter.Another tendency is to focus too much on the landingarea and not pay enough attention to airspeed. If toomuch airspeed is lost, a settling-with-power conditionmay result. Maintain the proper attitude during theapproach, and make sure you keep some forward airspeed and movement until close to the ground. Outsidevisual reference for airspeed and rate of closure maynot be available, especially when landing in anunlighted area, so pay special attention to the airspeedindicatorAlthough the landing light is a helpful aid when making night approaches, there is an inherent disadvantage.The portion of the landing area illuminated by the landing light seems higher than the dark area surroundingit. This effect can cause you to terminate the approachat too high an altitude, resulting in a settling-withpower condition and a hard landing.13-614-1Aeronautical decision making (ADM) is a systematicapproach to the mental process used by pilots to consistently determine the best course of action in responseto a given set of circumstances. The importance oflearning effective ADM skills cannot be overemphasized. While progress is continually being made in theadvancement of pilot training methods, aircraft equipment and systems, and services for pilots, accidentsstill occur. Despite all the changes in technology toimprove flight safety, one factor remains thesame—the human factor. It is estimated that approximately 65 percent of the total rotorcraft accidents arehuman factors related.Historically, the term “pilot error” has been used todescribe the causes of these accidents. Pilot errormeans that an action or decision made by the pilot wasthe cause of, or a contributing factor that lead to, theaccident. This definition also includes the pilot’s failure to make a decision or take action. From a broaderperspective, the phrase “human factors related” moreaptly describes these accidents since it is usually not asingle decision that leads to an accident, but a chain ofevents triggered by a number of factors.The poor judgment chain, sometimes referred to as the“error chain,” is a term used to describe this concept ofcontributing factors in a human factors related accident. Breaking one link in the chain normally is all thatis necessary to change the outcome of the sequence ofevents. The following is an example of the type of scenario illustrating the poor judgment chain.A helicopter pilot, with limited experience flying inadverse weather, wants to be back at his home airportin time to attend an important social affair. He isalready 30 minutes late. Therefore, he decides not torefuel his helicopter, since he should get back homewith at least 20 minutes of reserve. In addition, in spiteof his inexperience, he decides to fly through an area ofpossible thunderstorms in order to get back just beforedark. Arriving in the thunderstorm area, he encounterslightning, turbulence, and heavy clouds. Night isapproaching, and the thick cloud cover makes it verydark. With his limited fuel supply, he is not able to circumnavigate the thunderstorms. In the darkness andturbulence, the pilot becomes spatially disorientedwhile attempting to continue flying with visual reference to the ground instead of using what instrumentshe has to make a 180° turn. In the ensuing crash, thepilot is seriously injured and the helicopter completelydestroyed.By discussing the events that led to this accident, wecan understand how a series of judgmental errorscontributed to the final outcome of this flight. Forexample, one of the first elements that affected thepilot’s flight was a decision regarding the weather. Thepilot knew there were going to be thunderstorms in thearea, but he had flown near thunderstorms before andnever had an accident.Next, he let his desire to arrive at his destination ontime override his concern for a safe flight. For onething, in order to save time, he did not refuel the helicopter, which might have allowed him the opportunityto circumnavigate the bad weather. Then he overestimated his flying abilities and decided to use a route thattook him through a potential area of thunderstormactivity. Next, the pilot pressed on into obviously deteriorating conditions instead of changing course orlanding prior to his destination.On numerous occasions during the flight, the pilotcould have made effective decisions that may have prevented this accident. However, as the chain of eventsunfolded, each poor decision left him with fewer and
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发表于 2009-3-21 00:08:25
fewer options. Making sound decisions is the key topreventing accidents. Traditional pilot training hasHuman Factors—The study of howpeople interact with their environments. In the case of general aviation, it is the study of how pilotperformance is influenced by suchissues as the design of cockpits, thefunction of the organs of the body,the effects of emotions, and theinteraction and communicationwith the other participants of theaviation community, such as othercrew members and air traffic control personnel.14-2emphasized flying skills, knowledge of the aircraft, andfamiliarity with regulations. ADM training focuses onthe decision-making process and the factors that affecta pilot’s ability to make effective choices.ORIGINS OF ADM TRAININGThe airlines developed some of the first training programs that focused on improving aeronautical decisionmaking. Human factors-related accidents motivated theairline industry to implement crew resource management (CRM) training for flight crews. The focus ofCRM programs is the effective use of all availableresources; human resources, hardware, and information. Human resources include all groups routinelyworking with the cockpit crew (or pilot) who areinvolved in decisions that are required to operate aflight safely. These groups include, but are not limitedto: ground personnel, dispatchers, cabin crewmembers,maintenance personnel, external-load riggers, and airtraffic controllers. Although the CRM concept originated as airlines developed ways of facilitating crewcooperation to improve decision making in the cockpit,CRM principles, such as workload management, situational awareness, communication, the leadership roleof the captain, and crewmember coordination havedirect application to the general aviation cockpit. Thisalso includes single pilot operations since pilots ofsmall aircraft, as well as crews of larger aircraft, mustmake effective use of all available resources—humanresources, hardware, and information. You can alsorefer to AC 60-22, Aeronautical Decision Making,which provides background references, definitions, andother pertinent information about ADM training in thegeneral aviation environment. DEFINITIONSADM is a systematic approach to the mental process used by pilots to consistently determine the best course of action inresponse to a given set of circumstances.ATTITUDE is a personal motivational predisposition to respond to persons, situations, or events in a given manner that can,nevertheless, be changed or modified through training as sort of a mental shortcut to decision making.ATTITUDE MANAGEMENT is the ability to recognize hazardous attitudes in oneself and the willingness to modify them asnecessary through the application of an appropriate antidote thought.HEADWORK is required to accomplish a conscious, rational thought process when making decisions. Good decision makinginvolves risk identification and assessment, information processing, and problem solving.JUDGMENT is the mental process of recognizing and analyzing all pertinent information in a particular situation, a rationalevaluation of alternative actions in response to it, and a timely decision on which action to take.PERSONALITY is the embodiment of personal traits and characteristics of an individual that are set at a very early age andextremely resistant to change.POOR JUDGMENT CHAIN is a series of mistakes that may lead to an accident or incident. Two basic principles generallyassociated with the creation of a poor judgment chain are: (1) One bad decision often leads to another; and (2) as a string of baddecisions grows, it reduces the number of subsequent alternatives for continued safe flight. ADM is intended to break the poorjudgment chain before it can cause an accident or incident.RISK ELEMENTS IN ADM take into consideration the four fundamental risk elements: the pilot, the aircraft, the environment, andthe type of operation that comprise any given aviation situation.RISK MANAGEMENT is the part of the decision making process which relies on situational awareness, problem recognition, andgood judgment to reduce risks associated with each flight.SITUATIONAL AWARENESS is the accurate perception and understanding of all the factors and conditions within the fourfundamental risk elements that affect safety before, during, and after the flight.SKILLS and PROCEDURES are the procedural, psychomotor, and perceptual skills used to control a specific aircraft or itssystems. They are the airmanship abilities that are gained through conventional training, are perfected, and become almostautomatic through experience.STRESS MANAGEMENT is the personal analysis of the kinds of stress experienced while flying, the application of appropriatestress assessment tools, and other coping mechanisms.CREW RESOURCE MANAGEMENT (CRM) is the application of team management concepts in the flight deck environment. Itwas initially known as cockpit resource management, but as CRM programs evolved to include cabin crews, maintenancepersonnel, and others, the phrase crew resource management was adopted. This includes single pilots, as in most generalaviation aircraft. Pilots of small aircraft, as well as crews of larger aircraft, must make effective use of all available resources;human resources, hardware, and information. A current definition includes all groups routinely working with the cockpit crew whoare involved in decisions required to operate a flight safely. These groups include, but are not limited to: pilots, dispatchers, cabincrewmembers, maintenance personnel, and air traffic controllers. CRM is one way of addressing the challenge of optimizing thehuman/machine interface and accompanying interpersonal activities.Figure 14-1. These terms are used in AC 60-22 to explain concepts used in ADM training.14-3need to be taken to resolve the situation in the timeavailable. The expected outcome of each possibleaction should be considered and the risks assessedbefore you decide on a response to the situation.Your first thought was to pull up on the collective andyank back on the cyclic, but after weighing the consequences of possibly losing rotor r.p.m. and not beingable to maintain the climb rate sufficiently enough toclear the canyon wall, which is now only a hundredyards away, you realize that your only course is to tryto turn back to the landing zone on the canyon floor.IMPLEMENTING THE DECISION ANDEVALUATING THE OUTCOMEAlthough a decision may be reached and a course ofaction implemented, the decision-making process is notcomplete. It is important to think ahead and determinehow the decision could affect other phases of the flight.As the flight progresses, you must continue to evaluatethe outcome of the decision to ensure that it is producing the desired result.As you make your turn to the downwind, the airspeeddrops nearly to zero, and the helicopter becomes verydifficult to control. At this point, you must increase airspeed in order to maintain translational lift, but sincethe CG is aft of limits, you need to apply more forwardcyclic than usual. As you approach the landing zone
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with a high rate of descent, you realize that you are in apotential settling-with-power situation if you try totrade airspeed for altitude and lose ETL. Therefore, youwill probably not be able to terminate the approach in ahover. You decide to make as shallow of an approach aspossible and perform a run-on landing.The decision making process normally consists of several steps before you choose a course of action. To helpyou remember the elements of the decision-makingprocess, a six-step model has been developed using theacronym “DECIDE.” THE DECISION-MAKING PROCESSAn understanding of the decision-making process provides you with a foundation for developing ADMskills. Some situations, such as engine failures, requireyou to respond immediately using established procedures with little time for detailed analysis. Traditionally,pilots have been well trained to react to emergencies,but are not as well prepared to make decisions thatrequire a more reflective response. Typically during aflight, you have time to examine any changes thatoccur, gather information, and assess risk before reaching a decision. The steps leading to this conclusionconstitute the decision-making process.DEFINING THE PROBLEMProblem definition is the first step in the decision-makingprocess. Defining the problem begins with recognizingthat a change has occurred or that an expected changedid not occur. A problem is perceived first by thesenses, then is distinguished through insight and experience. These same abilities, as well as an objectiveanalysis of all available information, are used to determine the exact nature and severity of the problem.While doing a hover check after picking up fire fighters at the bottom of a canyon, you realize that you areonly 20 pounds under maximum gross weight. Whatyou failed to realize is that they had stowed some oftheir heaviest gear in the baggage compartment,which shifted the CG slightly behind the aft limits.Since weight and balance had never created anyproblems for you in the past, you did not bother to calculate CG and power required. You did, however, tryto estimate it by remembering the figures from earlierin the morning at the base camp. At a 5,000 footdensity altitude and maximum gross weight, the performance charts indicated you had plenty of excesspower. Unfortunately, the temperature was 93°F andthe pressure altitude at the pick up point was 6,200feet (DA = 9,600 feet). Since there was enough powerfor the hover check, you felt there was sufficientpower to take off.Even though the helicopter accelerated slowly duringthe takeoff, the distance between the helicopter and theground continued to increase. However, when youattempted to establish the best rate of climb speed, thenose wanted to pitch up to a higher than normal attitude, and you noticed that the helicopter was not gaining enough altitude in relation to the canyon wall acouple hundred yards ahead.CHOOSING A COURSE OF ACTIONAfter the problem has been identified, you must evaluate the need to react to it and determine the actions thatDetect the fact that a change has occurred.Estimate the need to counter or react to the change.Choose a desirable outcome for the success of the flight.Identify actions which could successfully control the change.Do the necessary action to adapt to the change.Evaluate the effect of the action.DECIDE MODELFigure 14-2. The DECIDE model can provide a framework foreffective decision making.14-4RISK MANAGEMENTDuring each flight, decisions must be made regardingevents that involve interactions between the four riskelements—the pilot in command, the aircraft, the environment, and the operation. The decision-makingprocess involves an evaluation of each of these risk elements to achieve an accurate perception of the flightsituation. One of the most important decisions that a pilot in command must make is the go/no-go decision. Evaluatingeach of these risk elements can help you decidewhether a flight should be conducted or continued. Letus evaluate the four risk elements and how they affectour decision making regarding the following situations.Pilot—As a pilot, you must continually make decisionsabout your own competency, condition of health, mentaland emotional state, level of fatigue, and many othervariables. For example, you are called early in the morning to make a long flight. You have had only a few hoursof sleep, and are concerned that the congestion you feelcould be the onset of a cold. Are you safe to fly?Aircraft—You will frequently base decisions on yourevaluations of the aircraft, such as its powerplant, performance, equipment, fuel state, or airworthiness. Pictureyourself in this situation: you are en route to an oil rig anhour’s flight from shore, and you have just passed theshoreline. Then you notice the oil temperature at the highend of the caution range. Should you continue out to sea,or return to the nearest suitable heliport/airport?Environment—This encompasses many elements notpilot or aircraft related. It can include such factors asweather, air traffic control, navaids, terrain, takeoff andRisk Elements—The four components of a flight that make up theoverall situation.NTSB—National TransportationSafety Board.landing areas, and surrounding obstacles. Weather is
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one element that can change drastically over time anddistance. Imagine you are ferrying a helicopter crosscountry and encounter unexpected low clouds and rainin an area of rising terrain. Do you try to stay underthem and “scud run,” or turn around, stay in the clear,and obtain current weather information?Operation—The interaction between you as the pilot,your aircraft, and the environment is greatly influencedby the purpose of each flight operation. You must evaluate the three previous areas to decide on the desirability of undertaking or continuing the flight as planned. Itis worth asking yourself why the flight is being made,how critical is it to maintain the schedule, and is thetrip worth the risks? For instance, you are tasked to takesome technicians into rugged mountains for a routinesurvey, and the weather is marginal. Would it be preferable to wait for better conditions to ensure a safe flight?How would the priorities change if you were tasked tosearch for cross-country skiers who had become lost indeep snow and radioed for help?ASSESSING RISKExamining NTSB reports and other accident researchcan help you to assess risk more effectively. For example, the accident rate decreases by nearly 50 percent oncea pilot obtains 100 hours, and continues to decrease untilthe 1,000 hour level. The data suggest that for the first500 hours, pilots flying VFR at night should establishhigher personal limitations than are required by the regulations and, if applicable, apply instrument flying skillsin this environment. Studies also indicate the types of flight activities thatare most likely to result in the most serious accidents.The majority of fatal general aviation accident causesfall under the categories of maneuvering flight,approaches, takeoff/initial climb, and weather. Delvingdeeper into accident statistics can provide some important details that can help you to understand the risksinvolved with specific flying situations. For example,maneuvering flight is one of the largest single produc-Figure 14-3. When situationally aware, you have an overview of the total operation and are not fixated on one perceived significant factor.RISK ELEMENTSPilot Aircraft Environment OperationFactors, such as weather,airport conditions, and theavailability of air traffic controlservices must be examined.The aircraft's performance,limitations, equipment, andairworthiness must be deter-mined.The pilot's fitness to fly mustbe evaluated includingcompetency in the aircraft,currency, and flight experience.To maintain situational awareness, an accurate perception must beattained of how the pilot, aircraft, environment, and operationcombine to affect the flight.SituationThe purpose of the flight is afactor which influences thepilot's decision on undertakingor continuing the flight.14-5ers of fatal accidents. Fatal accidents, which occurduring approach, often happen at night or in IFR conditions. Takeoff/initial climb accidents frequently are dueto the pilot’s lack of awareness of the effects of densityaltitude on aircraft performance or other improper takeoff planning resulting in loss of control during, orshortly after takeoff. The majority of weather-relatedaccidents occur after attempted VFR flight into IFRconditions.FACTORS AFFECTING DECISIONMAKINGIt is important to point out the fact that being familiarwith the decision-making process does not ensure thatyou will have the good judgment to be a safe pilot. Theability to make effective decisions as pilot incommand depends on a number of factors. Somecircumstances, such as the time available to make adecision, may be beyond your control. However, youcan learn to recognize those factors that can be managed, and learn skills to improve decision-makingability and judgment.PILOT SELF-ASSESSMENTThe pilot in command of an aircraft is directly responsible for, and is the final authority as to, the operation ofthat aircraft. In order to effectively exercise that responsibility and make effective decisions regarding theoutcome of a flight, you must have an understanding ofyour limitations. Your performance during a flight isaffected by many factors, such as health, recency ofexperience, knowledge, skill level, and attitude.Exercising good judgment begins prior to taking thecontrols of an aircraft. Often, pilots thoroughly checktheir aircraft to determine airworthiness, yet do notevaluate their own fitness for flight. Just as a checklistis used when preflighting an aircraft, a personalchecklist based on such factors as experience, currency, and comfort level can help determine if you areprepared for a particular flight. Specifying whenrefresher training should be accomplished and designating weather minimums, which may be higher thanthose listed in Title 14 of the Code of FederalRegulations (14 CFR) part 91, are elements that maybe included on a personal checklist. In addition to areview of personal limitations, you should use the I’MSAFE Checklist to further evaluate your fitness forflight. RECOGNIZING HAZARDOUS ATTITUDESBeing fit to fly depends on more than just your physical condition and recency of experience. For
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example,attitude affects the quality of your decisions. Attitudecan be defined as a personal motivational predisposition to respond to persons, situations, or events in agiven manner. Studies have identified five hazardousattitudes that can interfere with your ability to makesound decisions and exercise authority properly.Hazardous attitudes can lead to poor decision makingand actions that involve unnecessary risk. You mustexamine your decisions carefully to ensure that yourchoices have not been influenced by hazardousattitudes, and you must be familiar with positive alternatives to counteract the hazardous attitudes. Thesesubstitute attitudes are referred to as antidotes. Duringa flight operation, it is important to be able to recognize<51 101 201 501 <1000<200010,000 TotalPilot's Total Time (Hours)40302010Night VFR Accident RatePer 100,000 HoursFigure 14-4. Statistical data can identify operations that havemore risk.Illness—Do I have any symptoms?Medication—Have I been taking prescription orover-the-counter drugs?Stress—Am I under psychological pressure fromthe job? Worried about financial matters, healthproblems, or family discord?Fatigue—Am I tired and not adequately rested?Eating—Am I adequately nourished?Alcohol—Have I been drinking within 8 hours?Within 24 hours?I'M SAFE CHECKLISTFigure 14-5. Prior to flight, you should assess your fitness,just as you evaluate the aircraft’s airworthiness.14-6a hazardous attitude, correctly label the thought, andthen recall its antidote. STRESS MANAGEMENTEveryone is stressed to some degree all the time. A certain amount of stress is good since it keeps a personalert and prevents complacency. However, effects ofstress are cumulative and, if not coped with adequately,they eventually add up to an intolerable burden.Performance generally increases with the onset ofstress, peaks, and then begins to fall off rapidly as stresslevels exceed a person’s ability to cope. The ability tomake effective decisions during flight can be impairedby stress. Factors, referred to as stressors, can increasea pilot’s risk of error in the cockpit. There are several techniques to help manage the accumulation of life stresses and prevent stress overload.For example, including relaxation time in a busy schedule and maintaining a program of physical fitness canhelp reduce stress levels. Learning to manage timemore effectively can help you avoid heavy pressuresimposed by getting behind schedule and not meetingdeadlines. Take an assessment of yourself to determineyour capabilities and limitations and then set realisticgoals. In addition, avoiding stressful situations andencounters can help you cope with stress.USE OF RESOURCESTo make informed decisions during flight operations,you must be aware of the resources found both insideand outside the cockpit. Since useful tools and sourcesof information may not always be readily apparent,learning to recognize these resources is an essentialpart of ADM training. Resources must not only be iden-THE FIVE HAZARDOUS ATTITUDES1. Anti-Authority:"Don't tell me."This attitude is found in people who do not like anyone telling them what to do. In a sense, theyare saying, "No one can tell me what to do." They may be resentful of having someone tell themwhat to do, or may regard rules, regulations, and procedures as silly or unnecessary. However, itis always your prerogative to question authority if you feel it is in error.This is the attitude of people who frequently feel the need to do something, anything, immediately.They do not stop to think about what they are about to do; they do not select the best alternative,and they do the first thing that comes to mind.Many people feel that accidents happen to others, but never to them. They know accidents canhappen, and they know that anyone can be affected. They never really feel or believe that they willbe personally involved. Pilots who think this way are more likely to take chances and increase risk.Pilots who are always trying to prove that they are better than anyone else are thinking, "I can do it–I'll show them." Pilots with this type of attitude will try to prove themselves by taking risks in orderto impress others. While this pattern is thought to be a male characteristic, women are equallysusceptible.Pilots who think, "What's the use?" do not see themselves as being able to make a great deal ofdifference in what happens to them. When things go well, the pilot is apt to think that it is good luck.When things go badly, the pilot may feel that someone is out to get me, or attribute it to bad luck.The pilot will leave the action to others, for better or worse. Sometimes, such pilots will even goalong with unreasonable requests just to be a "nice guy."2. Impulsivity:"Do it quickly."3. Invulnerability:"It won't happen to me."4. Macho:"I can do it."5. Resignation:"What's the use?"Figure 14-6. You should examine your decisions carefully to ensure that your choices have not been influenced by a hazardousattitude.Takingchances isfoolish.Follow therules. They areusually right.It couldhappen to me.Not so fast.Think first.I'm nothelpless. I canmake adifference.HAZARDOUS ATTITUDES ANTIDOTESMacho—Brenda often brags to herfriends about her skills as a pilot and
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wants to impress them with her abilities.During her third solo flight she decides totake a friend for a helicopter ride.Anti-authority—In the air she thinks "It'sgreat to be up here without an instructorcriticizing everything I do. His do-it-by-thebook attitude takes all of the fun out offlying."Invulnerability—As she nears her friendsfarm, she remembers that it is about eightmiles from the closest airport. She thinks,"I'll land in the pasture behind the barn atSarah's farm. It won't be dangerous atall... the pasture is fenced and mowedand no animals are in the way. It's nomore dangerous than landing at aheliport."Impulsivity—After a short look, Brendainitiates an approach to her friend'spasture. Not realizing that she is landingwith a tail wind, she makes a hard landingin the pasture and nearly hits the fencewith the tail rotor before she gets thehelicopter stopped.Resignation—A policeman pulls up toinvestigate what he believes to be anemergency landing. As Brenda is walkingfrom the helicopter, she is supprised thatanyone observed her landing. Her firstthought is "if it weren't for my bad luck, thispoliceman wouldn't have come along andthis would have been a great afternoon."Figure 14-7. You must be able to identify hazardous attitudesand apply the appropriate antidote when needed.14-7tified, but you must develop the skills to evaluatewhether you have the time to use a particular resourceand the impact that its use will have upon the safety offlight. For example, the assistance of ATC may be veryuseful if you are lost. However, in an emergency situation when action needs be taken quickly, time may notbe available to contact ATC immediately.INTERNAL RESOURCESInternal resources are found in the cockpit duringflight. Since some of the most valuable internalresources are ingenuity, knowledge, and skill, you canexpand cockpit resources immensely by improvingthese capabilities. This can be accomplished by frequently reviewing flight information publications, suchas the CFRs and the AIM, as well as by pursuing additional training.A thorough understanding of all the equipment and systems in the aircraft is necessary to fully utilize allresources. For example, advanced navigation andautopilot systems are valuable resources. However, ifpilots do not fully understand how to use this equipment, or they rely on it so much that they becomecomplacent, it can become a detriment to safe flight.Checklists are essential cockpit resources for verifyingthat the aircraft instruments and systems are checked,set, and operating properly, as well as ensuring that theproper procedures are performed if there is a systemmalfunction or in-flight emergency. In addition, theFAA-approved rotorcraft flight manual, which isrequired to be carried on board the aircraft, is essentialfor accurate flight planning and for resolving in-flightequipment malfunctions. Other valuable cockpitresources include current aeronautical charts, and publications, such as the Airport/Facility Directory.Passengers can also be a valuable resource. Passengerscan help watch for traffic and may be able to provideinformation in an irregular situation, especially if theyare familiar with flying. A strange smell or sound mayalert a passenger to a potential problem. As pilot incommand, you should brief passengers before theflight to make sure that they are comfortable voicingany concerns.EXTERNAL RESOURCESPossibly the greatest external resources during flightare air traffic controllers and flight service specialists.ATC can help decrease pilot workload by providingtraffic advisories, radar vectors, and assistance in emergency situations. Flight service stations can provideupdates on weather, answer questions about airportconditions, and may offer direction-finding assistance.The services provided by ATC can be invaluable inenabling you to make informed in-flight decisions.WORKLOAD MANAGEMENTEffective workload management ensures that essentialoperations are accomplished by planning, prioritizing,and sequencing tasks to avoid work overload. Asexperience is gained, you learn to recognize futureworkload requirements and can prepare for highworkload periods during times of low workload.Reviewing the appropriate chart and setting radio frequencies well in advance of when they are neededhelps reduce workload as your flight nears the airport.In addition, you should listen to ATIS, ASOS, orAWOS, if available, and then monitor the tower frequency or CTAF to get a good idea of what trafficconditions to expect. Checklists should be performedwell in advance so there is time to focus on traffic andATC instructions. These procedures are especiallyimportant prior to entering a high-density traffic area,such as Class B airspace.To manage workload, items should be prioritized. Forexample, during any situation, and especially in anemergency, you should remember the phrase “aviate,STRESSORSPhysical Stress—Conditions associated with the environment, such as temperature andhumidity extremes, noise, vibration, and lack of oxygen.Physiological Stress—Physical conditions, such as fatigue, lack of physical fitness, sleeploss, missed meals (leading to low blood sugar levels), and illness.Psychological Stress—Social or emotional factors, such as a death in the family, a divorce, asick child, or a demotion at work. This type of stress may also be related to mental workload,such as analyzing a problem, navigating an aircraft, or making decisions.Figure 14-8. The three types of stressors that can affect a pilot’s performance.14-8navigate, and communicate.” This means that the firstthing you should do is make sure the helicopter is undercontrol. Then begin flying to an acceptable landing
