CFI PTS

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(2) c c The examiner shall select at least TASKs E and F. c REFERENCE: FAA-H-8083-9. To determine that the applicant exhibits instructional knowledge of the elements of the learning process by describing: 1. The definition and characteristics of learning. ã Changing behavior based on experience. Mnemonic: ? Ɣ !± students learn from any activity that furthers their purpose Ɣ "#± learning comes from experience; learning a physical skill requires actually performing the skill Ɣ ! $%± verbal, conceptual, perceptual, motor, problem solving and emotional Ɣ ± students need to react and respond, must interact with instructor and aircraft. 2. Practical application of the laws of learning. Ɣ $%# Students learn best when ready to learn; implies a singlemindedness to learn ã " Things most often repeated are best remembered ã Learning is strengthened by a satisfying or pleasant experience ã &$' Things learned first are best remembered ã c##' Students learn more from the real thing than a substitute or simulation ã #' Recent learning is best remembered 3. Factors involved in how people learn. Mnemonic: c ã ! (# A positive self-concept allows the student to be more receptive to new material while a negative self concept introduces psychological barriers that inhibit the learning process ã & $#% #' Proper sequence of training and providing time to process and learn the material. ã !&# )$: An effective instructor will organize training based on the psychological needs of a student. Ɣ # Formed when giving meaning to sensory input: sight 75%, hearing 13%, touch 6%, smell 3%, taste 3% Ɣ c#*) Grouping perceptions into a meaningful whole Ɣ $# Major force which governs progress and ability to learn 4. Recognition and proper use of the various levels of learning. ã : repeat back what has been instructed without necessarily understanding or be able to apply the knowledge. ã #%$#%#*: Able to repeat and comprehend what has been taught. ã !$#: Able to apply what is learned and perform in accordance with that knowledge. ã !$# The student is able to associate various learned elements with various other segments of learning or accomplishments..

(3) 5. Principles that are applied in learning a skill. Mnemonic: ã *#$*: Factual knowledge. The instructor provides step by step instruction that the student memorizes. ã $$*: No longer by memory. The student begins to be able to assess progress and make adjustments based on performance. ã &$#$*: The student devotes much less deliberate attention to performance. 6. Factors related to forgetting and retention. p Mnemonic: ã $ Praise stimulates remembering ã $# Association promotes recall ã # Learning with all senses is most effective ã % Favorable attitudes aid retention ã # Meaningful repetition aids recall p . Mnemonic: ã # Tendency to submerse unpleasant ideas in subconscious as a defense mechanism ã c# # Tendency to forget ideas because other experiences have overshadowed them ã

(4) Tendency to forget things which are not used. 7. How the transfer of learning affects the learning process. ã Application of what has been learned in one task to another subsequent task þ All new learning is based on previously learned experience þ Plan for transfer by organizing lessons in meaningful sequence ã $# : Learning one skill helps learn another þ Example: speedometer and airspeed indicator ã *$$# : Learning one skill hinders learning another þ Example: steering wheel vs. cyclic 8. How the formation of habit patterns affects the learning process. ã The formation of positive habits promotes learning and safety + +,c REFERENCE: FAA-H-8083-9. To determine that the applicant exhibits instructional knowledge of the elements related to human behavior by describing: 1. Control of human behavior. ã #$!'': (MBTI) attempts to explain behavior based on how individuals use their judgment and perception. ã c#$#%%#!$#): Instructor is responsible for determining the best way of teaching a student..

(5) 2. Development of student potential. ã Relationship between CFI and student has a profound impact on how much the student learns ã To a student, CFI is a symbol of authority CFI's challenge is to know what controls are best for what circumstances ã To mold a solid relationship depends on CFI's knowledge of the student's needs, drives and desires. 3. Relationship of human needs to behavior and learning. $!-.$)' %. ã )'!*$!: Maintenance of the human body, i.e. Air food water. A student that is not well will not perform well. ã ': A need to feel safe. ã +!#*#*: People seek to overcome feelings of loneliness and alienation. ã &: Humans have a need for a stable, firmly based, high level of self respect and respect from others. ã ! ($!/$#: ³be all you can be.´ þ Being problem focused. þ A concern about personal growth. þ The ability to have peak experiences. þ Incorporating an ongoing freshness of appreciation of life. 4. Relationship of defense mechanisms to student learning and pilot decision making. ã &#$# Emphasizing more positive quality to offset weak one ã # Blame own shortcomings on others, or weather ã $#$!/$# Can't accept real reasons for behavior, uses excuses ã

(6) #$! $!' Refuse to acknowledge disagreeable realities ã $# &$# Conscious attitudes/behaviors opposite of desires ã !*) Escape from frustration, physically or mentally ã **# Acting out anger in response to frustration ã *#$# Losing interest and giving up as a result of frustration 5. General rules which a flight instructor should follow during student training to ensure good human relations. ã ã ã ã ã ã ã ã ã. Provide and organized clearly defined syllabus. Help students integrate new ideas with what they have already know to ensure they keep and use the new information. Assume responsibility for only his or her own expectations not those of the students. Recognize the students need to control the pace. Use SBT exercises frequently. Use books, programmed instruction and computers. Refrain from spoon feeding. Set a cooperative learning climate. Create an opportunity for mutual planning..

(7) c REFERENCE: FAA-H-8083-9. To determine that the applicant exhibits instructional knowledge of the elements of the teaching process by describing: 1. Preparation of a lesson for a ground or flight instructional period. 4-4 ã Performance based objectives þ Objectives can come from syllabus or PTS þ What needs to be done and how it will be done þ Measurable, reasonable standards for the student ã Description of skill or behavior þ Desired outcome of the instruction þ Should be in concrete, measurable terms þ Not just ³knowledge of´ or ³awareness of´ ã Conditions þ Rules for demonstrating the skill or behavior þ Equipment, tools, reference materials, limitations ã Criteria þ Standards for accomplishment of the objective þ Be clear; leave no doubt whether objective is met þ When applicable, should be based on the PTS 2. Presentation of knowledge and skills, including the methods, which are suitable in particular situations. 4-10 A *0(12 ã Decide on topic. ã Write an outline. ã Rehearse the lesson. ã Make learning goals explicit Methods: ã : Classroom for presenting new material and association between theory and practice. ã

(8) &#$# &$# Instructor demonstration then student practices. ã %%%# ã + ã 3. Application, by the student, of the knowledge and skills presented by the instructor. 4-22 ã The students explain or perform the material or maneuver that was presented. 4. Review of the material presented and the evaluation of student performance and accomplishment. 4-22 ã The instructor reviews the material that was presented and the student demonstrates how well the lesson objectives were met.

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(10) REFERENCE: FAA-H-8083-9..

(11) To determine that the applicant exhibits instructional knowledge of the elements of teaching methods by describing: 1. The organization of a lesson, i.e., introduction, development, and conclusion. 4-8 ã c#%# þ Attention: Opening statement that grabs the attention of the student. þ Motivation: Why it is important to learn the material about to be presented. þ Overview: Brief introduction of the material to be covered. ã

(12) !&#: þ Past to Present: Chronological order. þ Simple to Complex: Lead the student from simple facts to complex facts to gain understanding. þ Known to Unknown: Teaching by association. þ Frequent to Least Used ã #!#: Must contain a review and assessment of the material and how they relate to the objectives. 2. The lecture method. 4-10 ã : Classroom environment for presenting new material and association between theory and practice. þ Teaching Lecture: þ Formal: þ Informal: þ Advantage and Disadvantage: 2. The guided discussion method. 4-13 ã %% %# Based on the idea that the student has a working knowledge of the material to be discussed. The goal is to draw out what the student knows instead of telling them lecture style. þ Overhead: Group question to stimulate thought. þ Rhetorical: Similar to the overhead just doesn¶t need an answer. þ Direct: Asking an individual a specific question. þ Reverse: Learner asked question that the instructor returns. þ Relay: Asked by a learner and the instructor relays it to another student. 3. The demonstration-performance method. 4-21 ã

(13) &#$# &$# Instructor demonstration then student practices. þ Explanation þ Demonstration þ Student Performance þ Instructor Supervision þ Evaluation 5. Computer/video assisted instruction. 4-26 ã &$%!$##* PC based test preps and study guides. ã # $$! Power Points and slide shows. ã

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(17) , c REFERENCE: FAA-H-8083-9..

(18) To determine that the applicant exhibits instructional knowledge of the elements of critique and evaluation by describing: 1. Purpose and characteristics of an effective critique. ã A critique should improve students¶ performance and provide them with something constructive with which to work and upon which they can build. cc ã þ Focused on student performance. ã !"! þ Considers student's entire performance. þ Considers requirements of the moment. ã $! þ Instructor must have credibility and trust. ã &)# þ Captures the significant points without overload. ã # þ Positive critique when earned. þ Negative critique points toward improvement. ã *$#/% þ Follows some pattern of organization. ' Chronological ' Order of importance ã )*) ! þ Student needs self-esteem, recognition and approval. ã þ Say what's wrong and how to fix it. )% ã c#3%# 5: Instructor leads a group discussion and members of the class are invited to critique. ã %#(!%5: Instructor asks the student to lead the critique. ã &$!! * 5: Divide the class into small groups and assign a specific area to analyze. ã c#%%$! %# 5 ' $#) %#: Another student presents the entire critique. ã ! (5: Require the student to critique personal performance. ã â# 5: Written critiques provide a record for the student. The instructor can devote more time. 2. Difference between critique and evaluation. ã Evaluation is making a judgment of students¶ abilities. Critique is providing comprehensive constructive feedback. 4. Characteristics of effective oral questions and what type to avoid. ã Apply to the subject. ã Brief and concise ã Be appropriate to the stage of training.

(19) ã Centered on one idea ã Present a challenge Types of questions to avoid ã //! þ Lots of parts and subparts. ã / þ Too general, covering wide area. ã ( þ More than one correct answer. ã +-!%&# þ Unclear about question's content. ã 65# þ Challenge to battle of wits with CFI. ã c!$# þ Unrelated to topic of discussion. Responses to student questions. ã Must be understood by CFI before answering ã May defer question until later unit or lesson ã CFI should admit not knowing an answer. Promise to get the answer or help student to look it up ã Encourage students to ask more questions. 5. Characteristics and development of effective written tests.(5-4) ã !$!' þ Consistent with repeated measurement ã ,$!%' þ Measures what it was intended to ã $!' þ Functionality for student ã ' þ Singleness of scoring, avoid bias ã &)## þ Measures overall objectives ã

(20) &#$# þ Measure differences in achievement Development ã Decide on the ! $##*. ã List indicators of the result of learning. (test completion standards) 6. Characteristics and uses of performance tests, specifically, the FAA practical test standards. ã CFI uses same standards preparing students for it ã Practical Test Standards (PTS) set standards for FAA examiners þ Broken down into areas of operation and tasks þ Areas of operation range from preflight to post-flight þ Criterion based..

(21) ã ã ã ã ã ã ã. ' Knowledge areas ' Flight procedures ' Maneuvers PTS are already set high - not minimum standards. !$!' þ Consistent with repeated measurement ,$!%' þ Measures what it was intended to $!' þ Functionality for student ' þ Singleness of scoring, avoid bias &)## þ Measures overall objectives

(22) &#$# þ Measure differences in achievement. cc cc

(23) c+ccc REFERENCE: FAA-H-8083-9. To determine that the applicant exhibits instructional knowledge of the elements of flight instructor characteristics and responsibilities by describing: 1. Major characteristics and qualifications of a professional flight instructor. ã. ã. ã ã ã. ã. ã. #' þ Straightforward and honest þ Facades will only cause student to lose confidence $# )%# þ As they are, with faults and problems þ Acceptance encourages learning #$!$$$#$#%)$ þ Important effect on professional image.

(24) &$# þ Calm, thoughtful, disciplined, but not somber. $ '$$#%$%### þ Emphasis on safety by CFI has long-lasting effect. þ CFI leads by example ± ³practice what you preach.´ !$#*$* þ Profanity detracts from professional image. þ Define and encourage proper use of aviation terms. ! (&&# þ CFI should seek improvement of own qualifications. A good pilot is always learning. þ CFI is the expert many pilots refer questions to..

(25) 4$! $# 17 789A:92 ã 2. Role of the flight instructor in dealing with student stress, anxiety, and psychological abnormalities. ã Calm, professional demeanor while maintaining control of the aircraft. ã Break training and maneuvers down into digestible chunks. 3. Flight instructor's responsibility with regard to student pilot supervision and surveillance. ã $!$# %#!!' þ Determine that student understands maneuver þ Instructor demonstrates, student practices þ Evaluation must be based on standards ' Consider student's experience and stage of training ' Not all PTS standards may apply on first practice ' But have a reasonable standard for completion þ Evaluate mastery of all elements of a maneuver not just overall performance þ Maintain training files ã !# þ Guidance and restraint for solo student operations þ Instructor alone determines student ready for solo þ Require performance of fundamental maneuvers þ Should be able to handle ordinary problems ' Traffic pattern congestion ' Change in active runway ' Unexpected crosswinds þ Instructor must retain control of situation 4. Flight instructor's authority and responsibility for endorsements and recommendations. ã !*)c##%&# þ From FAR Part 61 and Advisory Circular 61-65 þ Instructor must ensure student or pilot meets requirements prior to issuing endorsement þ ³You can never have too much ink´ ' When in doubt if an endorsement is needed, assume so þ Examples of endorsements: ' Student solo and cross-country ' Knowledge tests ' Practical tests - logbook and Form 8710-1 ' Flight reviews and instrument proficiency checks 7. Flight instructor's responsibility in the conduct of the required FAA flight review. ã )$##*$#%#%&# þ Flight reviews ' Not a test or check ride - assesses pilot's knowledge. ' Instructor must meet the qualifications in SFAR73. ' Provide awareness and flight training required..

(26) ã. ' Ensure that the pilot is competent and safe. ' Standards based on ratings held. þ Instrument proficiency checks ' Advisory Circular 61-98 and Instrument Rating PTS þ Aircraft checkouts/transitions ' CFI must be thoroughly familiar with aircraft & systems ' Record in logbook exact extent of checkout If pilot performance is insufficient, debrief on problem areas and schedule more instruction.. c c c c,c; REFERENCE: FAA-H-8083-9. To determine that the applicant exhibits instructional knowledge of the elements related to the planning of instructional activity by describing: 1. Development of a course of training. ã $##* þ Complete series of studies leading to attainment of a specific goal by determining the objectives and standards that may be tailored to Levels of Learning or Domains of Learning. 2. Content and use of a training syllabus. ã Step-by-step building block progression of learning ã Training syllabus can help keep up with þ Technology advances þ Increasingly complicated regulations ã Syllabus should be an abstract or digest of a course þ Brief yet comprehensive ã CFI may use own course or commercial product þ Order of actual training can be altered as necessary þ Consider relationships of blocks taken out of order ã Ground training focuses on cognitive domain ã Flight training on knowledge and psychomotor ã Can be used as a checklist of what to teach 3. Purpose, characteristics, proper use, and items of a lesson plan. ã þ Ensures the instructor has learned the lesson first þ Assists wise selection of material ' Minimizes unimportant material þ Due consideration given to each part of lesson þ Aid in presenting material in suitable sequence þ Outline of teaching procedure þ Relates lesson to its objectives þ Gives inexperienced instructor confidence þ Promotes uniformity of instruction ã )$$(6-7) þ #' ± lesson is a unified segment of instruction þ ## ± each lesson contains new material.

(27) ± each lesson is reasonable scope $$!' ± planned for conditions where the training will be conducted !"!' ± CFI may adapt/modify as needed !$# $##* ± should be taught so that relevance is clear to student þ c##$! ± use steps of teaching process þ Preparation, presentation, Application, evaluation ã - $#!$#!' þ Be familiar with the lesson plan ' CFI should study the plan and be familiar þ Use the lesson plan as a guide ' Avoids getting off track or omitting important details þ Adapt the lesson plan to the class or student ' If desired results aren't happening, change the approach þ Revise the lesson plan periodically ' Up-to-date for regulations and technology ' Availability of instructional aides & equipment ã c& $#!$# þ Objective þ Completion Standards þ Content of the lesson. ' Preflight discussion ' Review ' Introduction ' Post flight critique and preview. 4. Flexibility features of a course of training, syllabus, and lesson plan required to accommodate students with varying backgrounds, levels of experience, and ability. þ þ þ þ. ã. ã. ã. %#*%5$c## þ Analyze student's personality, thinking and ability þ No two students are alike þ Same methods of instruction are not equally effective on each student þ Learn the student's background, interests, temperament and way of thinking þ Instruction methods may change as student progresses through stages of training $#%$% &$# þ Flight instructors must continuously evaluate ' their own effectiveness ' Standard of learning ' Performance achieved by their students þ Desire to maintain pleasant personal relationship with student must not lead to acceptance of slow rate of learning or substandard performance þ An earnest student will not resent reasonable standards that are fairly and consistently applied &)$/#*).

(28) þ Flight instructors have a tremendous influence on students' perception of aviation þ Positive or negative impressions formed by ' The way instructors conduct themselves ' The attitudes instructors display ' The manner in which they develop their instruction þ Success depends largely on instructor's ability to present instruction so students have a positive image of aviation cc c c +< The examiner shall select TASK L and at least one other TASK.

(29) c REFERENCES: FAA-H-8083-25; AIM. To determine that the applicant exhibits instructional knowledge of the elements related to aero medical factors by describing: 1. Hypoxia, its symptoms, effects, and corrective action. 8-1-2. Effects of Altitude a. Hypoxia. 1. Hypoxia is a state of oxygen deficiency in the body sufficient to impair functions of the brain and other organs. Hypoxia from exposure to altitude is due only to the reduced barometric pressures encountered at altitude, for the concentration of oxygen in the atmosphere remains about 21 percent from the ground out to space. 2. Although deterioration in night vision occurs at a cabin pressure altitude as low as 5,000 feet, other significant effects of altitude hypoxia usually do not occur in the normal healthy pilot below 12,000 feet. From 12,000 to 15,000 feet of altitude, judgment, memory, alertness, coordination and ability to make calculations are impaired, and headache, drowsiness, dizziness and either a sense of well-being (euphoria) or belligerence occur. The effects appear following increasingly shorter periods of exposure to increasing altitude. In fact, pilot performance can seriously deteriorate within 15 minutes at 15,000 feet. 3. At cabin pressure altitudes above 15,000 feet, the periphery of the visual field grays out to a point where only central vision remains (tunnel vision). A blue coloration (cyanosis) of the fingernails and lips develops. The ability to take corrective and protective action is lost in 20 to 30 minutes at 18,000 feet and 5 to 12 minutes at 20,000 feet, followed soon thereafter by unconsciousness. 4. The altitude at which significant effects of hypoxia occur can be lowered by a number of factors. Carbon monoxide inhaled in smoking or from exhaust fumes, lowered hemoglobin (anemia), and certain medications can reduce the oxygen-carrying capacity of the blood to the degree that the amount of oxygen provided to body tissues will already be equivalent to the oxygen provided to the tissues when exposed to a cabin pressure altitude of several thousand.

(30) feet. Small amounts of alcohol and low doses of certain drugs, such as antihistamines, tranquilizers, sedatives and analgesics can, through their depressant action, render the brain much more susceptible to hypoxia. Extreme heat and cold, fever, and anxiety increase the body's demand for oxygen, and hence its susceptibility to hypoxia. . The effects of hypoxia are usually quite difficult to recognize, especially when they occur gradually. Since symptoms of hypoxia do not vary in an individual, the ability to recognize hypoxia can be greatly improved by experiencing and witnessing the effects of hypoxia during an altitude chamber "flight." The FAA provides this opportunity through aviation physiology training, which is conducted at the FAA Civil Aero medical Institute and at many military facilities across the U.S. To attend the Physiological Training Program at the Civil Aero medical Institute, Mike Monroney Aeronautical Center, Oklahoma City, OK, contact by telephone (405) 954-6212, or by writing Aerospace Medical Education Division, AAM-400, CAMI, Mike Monroney Aeronautical Center, P.O. Box 25082, Oklahoma City, OK 73125. 6. Hypoxia is prevented by heeding factors that reduce tolerance to altitude, by enriching the inspired air with oxygen from an appropriate oxygen system, and by maintaining a comfortable, safe cabin pressure altitude. For optimum protection, pilots are encouraged to use supplemental oxygen above 10,000 feet during the day and above 5,000 feet at night. The CFRs require that at the minimum, flight crew be provided with and use supplemental oxygen after 30 minutes of exposure to cabin pressure altitudes between 12,500 and 14,000 feet and immediately on exposure to cabin pressure altitudes above 14,000 feet. Every occupant of the aircraft must be provided with supplemental oxygen at cabin pressure altitudes above 15,000 feet. 2. Hyperventilation, its symptoms, effects, and corrective action. 8-1-3. Hyperventilation in Flight a. Hyperventilation, or an abnormal increase in the volume of air breathed in and out of the lungs, can occur subconsciously when a stressful situation is encountered in flight. As hyperventilation "blows off" excessive carbon dioxide from the body, a pilot can experience symptoms of lightheadedness, suffocation, drowsiness, tingling in the extremities, and coolness and react to them with even greater hyperventilation. Incapacitation can eventually result from incoordination, disorientation, and painful muscle spasms. Finally, unconsciousness can occur. b. The symptoms of hyperventilation subside within a few minutes after the rate and depth of breathing are consciously brought back under control. The buildup of carbon dioxide in the body can be hastened by controlled breathing in and out of a paper bag held over the nose and mouth. c. Early symptoms of hyperventilation and hypoxia are similar. Moreover, hyperventilation and hypoxia can occur at the same time. Therefore, if a pilot is using an oxygen system when symptoms are experienced, the oxygen regulator should immediately be set to deliver 100 percent oxygen, and then the system checked to assure that it has been functioning effectively before giving attention to rate and depth of breathing. 3. Middle ear and sinus problems, their causes, effects, and corrective action..

(31) Ear Block. 1. As the aircraft cabin pressure decreases during ascent, the expanding air in the middle ear pushes the Eustachian tube open, and by escaping down it to the nasal passages, equalizes in pressure with the cabin pressure. But during descent, the pilot must periodically open the Eustachian tube to equalize pressure. This can be accomplished by swallowing, yawning, tensing muscles in the throat, or if these do not work, by a combination of closing the mouth, pinching the nose closed, and attempting to blow through the nostrils (Valsalva maneuver). 2. Either an upper respiratory infection, such as a cold or sore throat, or a nasal allergic condition can produce enough congestion around the Eustachian tube to make equalization difficult. Consequently, the difference in pressure between the middle ear and aircraft cabin can build up to a level that will hold the Eustachian tube closed, making equalization difficult if not impossible. The problem is commonly referred to as an "ear block." 3. An ear block produces severe ear pain and loss of hearing that can last from several hours to several days. Rupture of the ear drum can occur in flight or after landing. Fluid can accumulate in the middle ear and become infected. 4. An ear block is prevented by not flying with an upper respiratory infection or nasal allergic condition. Adequate protection is usually not provided by decongestant sprays or drops to reduce congestion around the Eustachian tubes. Oral decongestants have side effects that can significantly impair pilot performance. . If an ear block does not clear shortly after landing, a physician should be consulted. Sinus Block. 1. During ascent and descent, air pressure in the sinuses equalizes with the aircraft cabin pressure through small openings that connect the sinuses to the nasal passages. Either an upper respiratory infection, such as a cold or sinusitis, or a nasal allergic condition can produce enough congestion around an opening to slow equalization, and as the difference in pressure between the sinus and cabin mounts, eventually plug the opening. This "sinus block" occurs most frequently during descent. 2. A sinus block can occur in the frontal sinuses, located above each eyebrow, or in the maxillary sinuses, located in each upper cheek. It will usually produce excruciating pain over the sinus area. A maxillary sinus block can also make the upper teeth ache. Bloody mucus may discharge from the nasal passages. 3. A sinus block is prevented by not flying with an upper respiratory infection or nasal allergic condition. Adequate protection is usually not provided by decongestant sprays or drops to reduce congestion around the sinus openings. Oral decongestants have side effects that can impair pilot performance. 4. If a sinus block does not clear shortly after landing, a physician should be consulted..

(32) 4. Spatial disorientation, its causes, effects, and corrective action. cllusions Leading to Spatial Disorientation. Various complex motions and forces and certain visual scenes encountered in flight can create illusions of motion and position. Spatial disorientation from these illusions can be prevented only by visual reference to reliable, fixed points on the ground or to flight instruments. Vhe leans. An abrupt correction of a banked attitude, which has been entered too slowly to stimulate the motion sensing system in the inner ear, can create the illusion of banking in the opposite direction. The disoriented pilot will roll the aircraft back into its original dangerous attitude, or if level flight is maintained, will feel compelled to lean in the perceived vertical plane until this illusion subsides. Coriolis illusion. An abrupt head movement in a prolonged constant-rate turn that has ceased stimulating the motion sensing system can create the illusion of rotation or movement in an entirely different axis. The disoriented pilot will maneuver the aircraft into a dangerous attitude in an attempt to stop rotation. This most overwhelming of all illusions in flight may be prevented by not making sudden, extreme head movements, particularly while making prolonged constantrate turns under IFR conditions. Graveyard spin. A proper recovery from a spin that has ceased stimulating the motion sensing system can create the illusion of spinning in the opposite direction. The disoriented pilot will return the aircraft to its original spin. Graveyard spiral. An observed loss of altitude during a coordinated constant-rate turn that has ceased stimulating the motion sensing system can create the illusion of being in a descent with the wings level. The disoriented pilot will pull back on the controls, tightening the spiral and increasing the loss of altitude. Somatogravic illusion. A rapid acceleration during takeoff can create the illusion of being in a nose up attitude. The disoriented pilot will push the aircraft into a nose low, or dive attitude. A rapid deceleration by a quick reduction of the throttles can have the opposite effect, with the disoriented pilot pulling the aircraft into a nose up, or stall attitude. cnversion illusion. An abrupt change from climb to straight and level flight can create the illusion of tumbling backwards. The disoriented pilot will push the aircraft abruptly into a nose low attitude, possibly intensifying this illusion. Elevator illusion. An abrupt upward vertical acceleration, usually by an updraft, can create the illusion of being in a climb. The disoriented pilot will push the aircraft into a nose low attitude. An abrupt downward vertical acceleration, usually by a downdraft, has the opposite effect, with the disoriented pilot pulling the aircraft into a nose up attitude. False horizon. Sloping cloud formations, an obscured horizon, a dark scene spread with ground lights and stars, and certain geometric patterns of ground light can create illusions of not being.

(33) aligned correctly with the actual horizon. The disoriented pilot will place the aircraft in a dangerous attitude. Auto kinesis. In the dark, a static light will appear to move about when stared at for many seconds. The disoriented pilot will lose control of the aircraft in attempting to align it with the light. 5. Motion sickness, its causes, effects, and corrective action. 1. Motion is sensed by the brain through three different pathways of the nervous system that send signals coming from the inner ear (sensing motion, acceleration, and gravity), the eyes (vision), and the deeper tissues of the body surface (proprioceptors). When the body is moved intentionally, for example, when we walk, the input from all three pathways is coordinated by our brain. When there is unintentional movement of the body, as occurs during motion when driving in a car, the brain is not coordinating the input, and there is thought to be discoordination or conflict among the input from the three pathways. It is hypothesized that the conflict among the inputs is responsible for motion sickness. 2. The symptoms of motion sickness include nausea, vomiting, and dizziness (vertigo). Other common signs are sweating and a general feeling of discomfort and not feeling well. 3. Always ride where your eyes will see the same motion that your body and inner ears feel. þ þ þ. In an airplane, sit by the window and look outside. Also, in a plane, choose a seat over the wings where the motion is minimized. Avoid strong odors and spicy or greasy foods that do not agree with you (immediately before and during your travel).. 6. Effects of alcohol and drugs, and their relationship to safety. ÷edication. 1. Pilot performance can be seriously degraded by both prescribed and over-the-counter medications, as well as by the medical conditions for which they are taken. Many medications, such as tranquilizers, sedatives, strong pain relievers, and cough-suppressant preparations, have primary effects that may impair judgment, memory, alertness, coordination, vision, and the ability to make calculations. Others, such as antihistamines, blood pressure drugs, muscle relaxants, and agents to control diarrhea and motion sickness, have side effects that may impair the same critical functions. Any medication that depresses the nervous system, such as a sedative, tranquilizer or antihistamine, can make a pilot much more susceptible to hypoxia. 2. The CFRs prohibit pilots from performing crewmember duties while using any medication that affects the faculties in any way contrary to safety. The safest rule is not to fly as a crewmember while taking any medication, unless approved to do so by the FAA. Alcohol..

(34) 1. Extensive research has provided a number of facts about the hazards of alcohol consumption and flying. As little as one ounce of liquor, one bottle of beer or four ounces of wine can impair flying skills, with the alcohol consumed in these drinks being detectable in the breath and blood for at least 3 hours. Even after the body completely destroys a moderate amount of alcohol, a pilot can still be severely impaired for many hours by hangover. There is simply no way of increasing the destruction of alcohol or alleviating a hangover. Alcohol also renders a pilot much more susceptible to disorientation and hypoxia. 2. A consistently high alcohol related fatal aircraft accident rate serves to emphasize that alcohol and flying are a potentially lethal combination. The CFRs prohibit pilots from performing crewmember duties within 8 hours after drinking any alcoholic beverage or while under the influence of alcohol. However, due to the slow destruction of alcohol, a pilot may still be under influence 8 hours after drinking a moderate amount of alcohol. Therefore, an excellent rule is to allow at least 12 to 24 hours between "bottle and throttle," depending on the amount of alcoholic beverage consumed. 7. Carbon monoxide poisoning, its symptoms, effects, and corrective action. 8-1-4. Carbon ÷onoxide Poisoning in Flight a. Carbon monoxide is a colorless, odorless, and tasteless gas contained in exhaust fumes. When breathed even in minute quantities over a period of time, it can significantly reduce the ability of the blood to carry oxygen. Consequently, effects of hypoxia occur. b. Most heaters in light aircraft work by air flowing over the manifold. Use of these heaters while exhaust fumes are escaping through manifold cracks and seals is responsible every year for several nonfatal and fatal aircraft accidents from carbon monoxide poisoning. c. A pilot who detects the odor of exhaust or experiences symptoms of headache, drowsiness, or dizziness while using the heater should suspect carbon monoxide poisoning, and immediately shut off the heater and open air vents. If symptoms are severe or continue after landing, medical treatment should be sought. 8. How evolved gas from scuba diving can affect a pilot during flight. Decompression Sickness After Scuba Diving. 1. A pilot or passenger who intends to fly after scuba diving should allow the body sufficient time to rid itself of excess nitrogen absorbed during diving. If not, decompression sickness due to evolved gas can occur during exposure to low altitude and create a serious in-flight emergency. 2. The recommended waiting time before going to flight altitudes of up to 8,000 feet is at least 12 hours after diving which has not required controlled ascent (no decompression stop diving), and at least 24 hours after diving which has required controlled ascent (decompression stop diving). The waiting time before going to flight altitudes above 8,000 feet should be at least 24 hours after any SCUBA dive. These recommended altitudes are actual flight altitudes above.

(35) mean sea level (AMSL) and not pressurized cabin altitudes. This takes into consideration the risk of decompression of the aircraft during flight. 8. Fatigue, its effects and corrective action. Fatigue. 1. Fatigue continues to be one of the most treacherous hazards to flight safety, as it may not be apparent to a pilot until serious errors are made. Fatigue is best described as either acute (shortterm) or chronic (long-term). 2. A normal occurrence of everyday living, acute fatigue is the tiredness felt after long periods of physical and mental strain, including strenuous muscular effort, immobility, heavy mental workload, strong emotional pressure, monotony, and lack of sleep. Consequently, coordination and alertness, so vital to safe pilot performance, can be reduced. Acute fatigue is prevented by adequate rest and sleep, as well as by regular exercise and proper nutrition. 3. Chronic fatigue occurs when there is not enough time for full recovery between episodes of acute fatigue. Performance continues to fall off, and judgment becomes impaired so that unwarranted risks may be taken. Recovery from chronic fatigue requires a prolonged period of rest. PERSONAL CHECKLcSV. c .

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(37) cllness ÷edication Stress Alcohol Fatigue Emotion. + ,c c

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(39) REFERENCES: FAA-H-8083-25; AC 90-48; AIM. To determine that the applicant exhibits instructional knowledge of the elements related to visual scanning and collision avoidance by describing: 1. Relationship between a pilot's physical or mental condition and vision. In darkness, vision becomes more sensitive to light, a process called dark adaptation. Although exposure to total darkness for at least 30 minutes is required for complete dark adaptation, a pilot can achieve a moderate degree of dark adaptation within 20 minutes under dim red cockpit lighting. Since red light severely distorts colors, especially on aeronautical charts, and can cause serious difficulty in focusing the eyes on objects inside the aircraft, its use is advisable only.

(40) where optimum outside night vision capability is necessary. Even so, white cockpit lighting must be available when needed for map and instrument reading, especially under IFR conditions. Dark adaptation is impaired by exposure to cabin pressure altitudes above 5,000 feet, carbon monoxide inhaled in smoking and from exhaust fumes, deficiency of Vitamin A in the diet, and by prolonged exposure to bright sunlight. Since any degree of dark adaptation is lost within a few seconds of viewing a bright light, a pilot should close one eye when using a light to preserve some degree of night vision. 2. Environmental conditions and optical illusions that affect vision. cllusions Leading to Landing Errors. Various surface features and atmospheric conditions encountered in landing can create illusions of incorrect height above and distance from the runway threshold. Landing errors from these illusions can be prevented by anticipating them during approaches, aerial visual inspection of unfamiliar airports before landing, using electronic glide slope or VASI systems when available, and maintaining optimum proficiency in landing procedures. 1. Runway width illusion. A narrower-than-usual runway can create the illusion that the aircraft is at a higher altitude than it actually is. The pilot who does not recognize this illusion will fly a lower approach, with the risk of striking objects along the approach path or landing short. A wider-than-usual runway can have the opposite effect, with the risk of leveling out high and landing hard or overshooting the runway. 2. Runway and terrain slopes illusion. An up sloping runway, up sloping terrain, or both, can create the illusion that the aircraft is at a higher altitude than it actually is. The pilot who does not recognize this illusion will fly a lower approach. A down sloping runway, down sloping approach terrain, or both, can have the opposite effect. 3. Featureless terrain illusion. An absence of ground features, as when landing over water, darkened areas, and terrain made featureless by snow, can create the illusion that the aircraft is at a higher altitude than it actually is. The pilot who does not recognize this illusion will fly a lower approach. 4. Atmospheric illusions. Rain on the windscreen can create the illusion of greater height, and atmospheric haze the illusion of being at a greater distance from the runway. The pilot who does not recognize these illusions will fly a lower approach. Penetration of fog can create the illusion of pitching up. The pilot who does not recognize this illusion will steepen the approach, often quite abruptly. . Ground lighting illusions. Lights along a straight path, such as a road, and even lights on moving trains can be mistaken for runway and approach lights. Bright runway and approach lighting systems, especially where few lights illuminate the surrounding terrain, may create the illusion of less distance to the runway. The pilot who does not recognize this illusion will fly a higher approach. Conversely, the pilot overflying terrain which has few lights to provide height cues may make a lower than normal approach..

(41) 3. ³See and avoid´ concept. FAR 91.113 See and Avoid. Vigilance for other air traffic must be maintained at all times by each pilot 3. Practice of ³time sharing´ of attention inside and outside the cockpit. Studies show that the time a pilot spends on visual tasks inside the cabin should represent no more than 1/4 to 1/3 of the scan time outside, or no more than 4 to 5 seconds on the instrument panel for every 16 seconds outside. Since the brain is already trained to process sight information that is presented from left to right, one may find it easier to start scanning over the left shoulder and proceed across the windshield to the right. 4. Proper visual scanning technique. 1. Scanning the sky for other aircraft is a key factor in collision avoidance. It should be used continuously by the pilot and copilot (or right seat passenger) to cover all areas of the sky visible from the cockpit. Although pilots must meet specific visual acuity requirements, the ability to read an eye chart does not ensure that one will be able to efficiently spot other aircraft. Pilots must develop an effective scanning technique which maximizes one's visual capabilities. The probability of spotting a potential collision threat obviously increases with the time spent looking outside the cockpit. Thus, one must use timesharing techniques to efficiently scan the surrounding airspace while monitoring instruments as well. 2. While the eyes can observe an approximate 200 degree arc of the horizon at one glance, only a very small center area called the fovea, in the rear of the eye, has the ability to send clear, sharply focused messages to the brain. All other visual information that is not processed directly through the fovea will be of less detail. An aircraft at a distance of 7 miles which appears in sharp focus within the foveal center of vision would have to be as close as 7/10 of a mile in order to be recognized if it were outside of foveal vision. Because the eyes can focus only on this narrow viewing area, effective scanning is accomplished with a series of short, regularly spaced eye movements that bring successive areas of the sky into the central visual field. Each movement should not exceed 10 degrees, and each area should be observed for at least 1 second to enable detection. Although horizontal back-and-forth eye movements seem preferred by most pilots, each pilot should develop a scanning pattern that is most comfortable and then adhere to it to assure optimum scanning. 3. Pilots should realize that their eyes may require several seconds to refocus when switching views between items in the cockpit and distant objects. The eyes will also tire more quickly when forced to adjust to distances immediately after close-up focus, as required for scanning the instrument panel. Eye fatigue can be reduced by looking from the instrument panel to the left wing past the wing tip to the center of the first scan quadrant when beginning the exterior scan. After having scanned from left to right, allow the eyes to return to the cabin along the right wing from its tip inward. Once back inside, one should automatically commence the panel scan..

(42) 4. Effective scanning also helps avoid "empty-field myopia." This condition usually occurs when flying above the clouds or in a haze layer that provides nothing specific to focus on outside the aircraft. This causes the eyes to relax and seek a comfortable focal distance which may range from 10 to 30 feet. For the pilot, this means looking without seeing, which is dangerous. 6. Relationship between poor visual scanning habits, aircraft speed differential and increased collision risk. ã ã ã. If the pilot does not use proper visual scanning techniques and/or fixates in the cockpit his/her risks of a midair collision will increase greatly Studies have shown that the minimum time required for a pilot to spot the traffic, identify it, realize it¶s a collision threat, react, and maneuver the aircraft is at least 12.5 seconds Therefore at higher speeds extra vigilance must be maintained because of the higher closure rate . 7. Appropriate clearing procedures. ã ã ã ã ã ã ã ã. Proper clearing occurs before the helicopter even moves Ensure that the taxiways are clear of hazards/obstructions Ensure the runway is clear of hazards/obstructions and approaching aircraft During maneuvers a pilot should perform clearing turns to look for aircraft in the blind spots Entering an airport traffic pattern extra vigilance must be maintained because of the potential for a high volume of traffic Obtain clearance or utilize the CTAF Enter at the proper position and altitude Keep up a constant scan. 9. Situations which involve the greatest collision risk. ã ã ã ã ã. Collisions can happen anywhere, increased hazard areas include: Airways especially near VORs Airports VFR corridors Practice areas.

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(44) c c c c REFERENCE: FAA-H-8083-9. To determine that the applicant exhibits instructional knowledge of the elements related to use of distractions during flight training by describing: 1. Flight situations where pilot distraction can be a causal factor related to aircraft accidents. Distractions cnterruptions.

(45) A distraction is an unexpected event that causes the student¶s attention to be momentarily diverted. Students must learn to decide whether or not a distraction warrants further attention or action on their part. Once this has been decided, the students must either turn their attention back to what they were doing, or act on the distraction. 2. Selection of realistic distractions for specific flight situations. Use distractions that will not adversely affect the students learning or compromise the safety of flight. 3. Relationship between division of attention and flight instructor use of distractions. . cnterruptions An interruption is an unexpected event for which the student voluntarily suspends performance of one task in order to complete a different one. Interruptions are a significant source of errors and students must be made aware of the potential for errors caused by interruptions and develop procedures for dealing with them. A classic example is an interruption that occurs while a student is following the steps in a written procedure or checklist. The student puts down the checklist, deals with the interruption, and then returns to the procedure²but erroneously picks up at a later point in the procedure, omitting one or more steps. For many kinds of tasks, attention switching is the only way to accomplish multitasking. For example, it is generally impossible to look at two different things at the same time. The area of focused vision (called the fovea) is only a few degrees in span and can only be directed to one location at a time. Similarly, people cannot listen to two conversations at the same time. While both conversations fall upon the ears at once, people must devote their attention to the comprehension of one, to the exclusion of the other. 4. Difference between proper use of distractions and harassment. Distractions allow the student to decide on the import tasks while harassment inhibits the student¶s ability to make proper decisions and learn.

(46) c cc REFERENCE: FAA-H-8083-21. To determine that the applicant exhibits instructional knowledge of the elements related to principles of flight by describing: 1. Characteristics of different rotor systems. VHE ÷AcN ROVOR SYSVE÷ The rotor system found on helicopters can consist of a single main rotor or dual rotors. With most dual rotors, the rotors turn in opposite directions so the torque from one rotor is opposed by the torque of the other. This cancels the turning tendencies. In general, a rotor system can be classified as fully articulated, semi rigid, or rigid..

(47) FULLY ARVcCULAVED ROVOR SYSVE÷ A fully articulated rotor system usually consists of three or more rotor blades. The blades are allowed to flap, feather, and lead or lag independently of each other. Each rotor blade is attached to the rotor hub by a horizontal hinge, called the flapping hinge, which permits the blades to flap up and down. Each blade can move up and down independently of the others. The flapping hinge may be located at varying distances from the rotor hub, and there may be more than one. The position is chosen by each manufacturer, primarily with regard to stability and control. Each rotor blade is also attached to the hub by a vertical hinge, called a drag or lag hinge, that permits each blade, independently of the others, to move back and forth in the plane of the rotor disc. Dampers are normally incorporated in the design of this type of rotor system to prevent excessive motion about the drag hinge. The purpose of the drag hinge and dampers is to absorb the acceleration and deceleration of the rotor blades. The blades of a fully articulated rotor can also be feathered, or rotated about their span wise axis. To put it more simply, feathering means the changing of the pitch angle of the rotor blades. SE÷cRcGcD ROVOR SYSVE÷ A semi rigid rotor system allows for two different movements, flapping and feathering. This system is normally comprised of two blades, which are rigidly attached to the rotor hub. The hub is then attached to the rotor mast by a trunnion bearing or teetering hinge. This allows the blades to see-saw or flap together. As one blade flaps down, the other flaps up. Feathering is accomplished by the feathering hinge, which changes the pitch angle of the blade. RcGcD ROVOR SYSVE÷ The rigid rotor system is mechanically simple, but structurally complex because operating loads must be absorbed in bending rather than through hinges. In this system, the blades cannot flap or lead and lag, but they can be feathered. 2. Effect of lift, weight, thrust, and drag during various flight maneuvers. LcFV ÷AGNUS EFFECV The explanation of lift can best be explained by looking at a cylinder rotating in an airstream. The local velocity near the cylinder is composed of the airstream velocity and the cylinder¶s rotational velocity, which decreases with distance from the cylinder. On a cylinder, which is rotating in such a way that the top surface area is rotating in the same direction as the airflow, the local velocity at the surface is high on top and low on the bottom. As shown in figure 2-7, at point ³A,´ a stagnation point exists where the airstream line that impinges on the surface splits; some air goes over and some under. Another stagnation point exists at ³B,´ where the two air streams rejoin and resume at identical velocities. We now have up wash ahead of the rotating cylinder and downwash at the rear. The difference in surface velocity accounts for a difference in pressure, with the pressure being lower on the top than the bottom. This low pressure area produces an upward force known as the ³Magnus Effect.´ This mechanically induced circulation.

(48) illustrates the relationship between circulation and lift. An airfoil with a positive angle of attack develops air circulation as its sharp trailing edge forces the rear stagnation point to be aft of the trailing edge, while the front stagnation point is below the leading edge. BERNOULLc S PRcNCcPLE Air flowing over the top surface accelerates. The airfoil is now subjected to Bernoulli¶s Principle or the ³venture effect.´ As air velocity increases through the constricted portion of a venturi tube, the pressure decreases. Compare the upper surface of an airfoil with the constriction in a venturi tube that is narrower in the middle than at the ends. The upper half of the venturi tube can be replaced by layers of undisturbed air. Thus, as air flows over the upper surface of an airfoil, the camber of the airfoil causes an increase in the speed of the airflow. The increased speed of airflow results in a decrease in pressure on the upper surface of the airfoil. At the same time, air flows along the lower surface of the airfoil, building up pressure. The combination of decreased pressure on the upper surface and increased pressure on the lower surface results in an upward force. As angle of attack is increased, the production of lift is increased. More up wash is created ahead of the airfoil as the leading edge stagnation point moves under the leading edge, and more downwash is created aft of the trailing edge. Total lift now being produced is perpendicular to relative wind. In summary, the production of lift is based upon the airfoil creating circulation in the airstream (Magnus Effect) and creating differential pressure on the airfoil (Bernoulli¶s Principle). NEWVON S VHcRD LAW OF ÷OVcON Additional lift is provided by the rotor blades lower surface as air striking the underside is deflected down-ward. According to Newton¶s Third Law of Motion, ³for every action there is an equal and opposite reaction,´ the air that is deflected downward also produces an upward (lifting) reaction. Since air is much like water, the explanation for this source of lift may be compared to the planning effect of skis on water. The lift which supports the water skis (and the skier) is the force caused by the impact pressure and the deflection of water from the lower surfaces of the skis. Under most flying conditions, the impact pressure and the deflection of air from the lower surface of the rotor blade provides a comparatively small percentage of the total lift. The majority of lift is the result of decreased pressure above the blade, rather than the increased pressure below it. WEcGHV Normally, weight is thought of as being a known, fixed value, such as the weight of the helicopter, fuel, and occupants. To lift the helicopter off the ground vertically, the rotor system must generate enough lift to overcome or offset the total weight of the helicopter and its occupants. This is accomplished by increasing the pitch angle of the main rotor blades. The weight of the helicopter can also be influenced by aerodynamic loads. When you bank a helicopter while maintaining a constant altitude, the ³G´ load or load factor increases. Load factor is the ratio of the load supported by the main rotor system to the actual weight of the helicopter and its contents. In steady-state flight, the helicopter has a load factor of one, which means the main rotor system is supporting the actual total weight of the helicopter. If you increase the bank angle to 60°, while still maintaining a constant altitude, the load factor increases to two. In this case, the main rotor system has to support twice the weight of the helicopter and its contents. [Figure 2-11] Disc loading of a helicopter is the ratio of weight to the.

(49) total main rotor disc area, and is determined by dividing the total helicopter weight by the rotor disc area, which is the area swept by the blades of a rotor. Disc area can be found by using the span of one rotor blade as the radius of a circle and then determining the area the blades encompass during a complete rotation. As the helicopter is maneuvered, disc loading changes. The higher the loading, the more power you need to maintain rotor speed. VHRUSV Thrust, like lift, is generated by the rotation of the main rotor system. In a helicopter, thrust can be forward, rearward, sideward, or vertical. The resultant of lift and thrust determines the direction of movement of the helicopter. The solidity ratio is the ratio of the total rotor blade area, which is the combined area of all the main rotor blades, to the total rotor disc area. This ratio provides a means to measure the potential for a rotor system to provide thrust. The tail rotor also produces thrust. The amount of thrust is variable through the use of the antitorque pedals and is used to control the helicopter¶s yaw.. DRAG The force that resists the movement of a helicopter through the air and is produced when lift is developed is called drag. Drag always acts parallel to the relative wind. Total drag is composed of three types of drag: profile, induced, and parasite. PROFcLE DRAG Profile drag develops from the frictional resistance of the blades passing through the air. It does not change significantly with the airfoil¶s angle of attack, but increases moderately when airspeed increases. Profile drag is composed of form drag and skin friction. Form drag results from the turbulent wake caused by the separation of airflow from the surface of a structure. The amount of drag is related to both the size and shape of the structure that protrudes into the relative wind. [Figure 2-12] Skin friction is caused by surface roughness. Even though the surface appears smooth, it may be quite rough when viewed under a microscope. A thin layer of air clings to the rough surface and creates small eddies that contribute to drag. cNDUCED DRAG Induced drag is generated by the airflow circulation around the rotor blade as it creates lift. The high-pressure area beneath the blade joins the low-pressure air above the blade at the trailing edge and at the rotor tips. This causes a spiral, or vortex, which trails behind each blade whenever lift is being produced. These vortices deflect the airstream downward in the vicinity of the blade, creating an increase in downwash. Therefore, the blade operates in an average relative wind that is inclined downward and rearward near the blade. Because the lift produced by the blade is perpendicular to the relative wind, the lift is inclined aft by the same amount. The component of lift that is acting in a rearward direction is induced drag. [Figure 2-13] As the air pressure differential increases with an increase in angle of attack, stronger vortices form, and induced drag increases. Since the blade¶s angle of attack is usually lower at higher airspeeds, and higher at low speeds, induced drag decreases as airspeed increases and increases as airspeed decreases. Induced drag is the major cause of drag at lower airspeeds..

(50) PARAScVE DRAG Parasite drag is present any time the helicopter is moving through the air. This type of drag increases with airspeed. Nonlifting components of the helicopter, such as the cabin, rotor mast, tail, and landing gear, contribute to parasite drag. Any loss of momentum by the airstream, due to such things as openings for engine cooling, creates additional parasite drag. Because of its rapid increase with increasing airspeed, parasite drag is the major cause of drag at higher airspeeds. Parasite drag varies with the square of the velocity. Doubling the airspeed increases the parasite drag four times. VOVAL DRAG Total drag for a helicopter is the sum of all three drag forces. [Figure 2-14] As airspeed increases, parasite drag increases, while induced drag decreases. Profile drag remains relatively constant throughout the speed range with some increase at higher airspeeds. Combining all drag forces results in a total drag curve. The low point on the total drag curve shows the airspeed at which drag is minimized. This is the point where the lift-to-drag ratio is greatest and is referred to as L/Dmax. At this speed, the total lift capacity of the helicopter, when compared to the total drag of the helicopter, is most favorable. This is important in helicopter performance. L/Dmax²Vhe maximum ratio between total lift (L) and the total drag (D). Vhis point provides the best glide speed. Any deviation from best glide speed increases drag and reduces the distance you can glide. . 3. Retreating blade stall. REVREAVcNG BLADE SVALL In forward flight, the relative airflow through the main rotor disc is different on the advancing and retreating side. The relative airflow over the advancing side is higher due to the forward speed of the helicopter, while the relative airflow on the retreating side is lower. This dissymmetry of lift increases as forward speed increases. To generate the same amount of lift across the rotor disc, the advancing blade flaps up while the retreating blade flaps down. This causes the angle of attack to decrease on the advancing blade, which reduces lift, and increase on the retreating blade, which increases lift. As the forward speed increases, at some point the low blade speed on the retreating blade, together with its high angle of attack, causes a loss of lift (stall). Retreating blade stall is a major factor in limiting a helicopter¶s top forward speed (VNE) and can be felt developing by a low frequency vibration, pitching up of the nose, and a roll in the direction of the retreating blade. High weight, low rotor r.p.m., high density altitude, turbulence and/or steep, abrupt turns are all conducive to retreating blade stall at high forward airspeeds. As altitude is increased, higher blade angles are required to maintain lift at a given airspeed. Thus, retreating blade stall is encountered at a lower forward airspeed at altitude. Most manufacturers publish charts and graphs showing a VNE decrease with altitude. When recovering from a retreating blade stall condition, moving the cyclic aft only worsens the stall as aft cyclic produces a flare effect, thus increasing angles of attack. Pushing forward on the cyclic also deepens the stall as the angle of attack on the retreating blade is increased. Correct.

(51) recovery from retreating blade stall requires the collective to be lowered first, which reduces blade angles and thus angle of attack. Aft cyclic can then be used to slow the helicopter. 4. Torque effect. An important consequence of producing thrust is torque. As stated before, for every action there is an equal and opposite reaction. Therefore, as the engine turns the main rotor system in a counterclockwise direction, the helicopter fuselage turns clockwise. The amount of torque is directly related to the amount of engine power being used to turn the main rotor system. Remember, as power changes, torque changes. To counteract this torque-induced turning tendency, an antitorque rotor or tail rotor is incorporated into most helicopter designs. You can vary the amount of thrust produced by the tail rotor in relation to the amount of torque produced by the engine. As the engine supplies more power, the tail rotor must produce more thrust. This is done through the use of antitorque pedals. 5. Dissymmetry of lift. DcSSY÷÷EVRY OF LcFV When the helicopter moves through the air, the relative airflow through the main rotor disc is different on the advancing side than on the retreating side. The relative wind encountered by the advancing blade is increased by the forward speed of the helicopter, while the relative wind speed acting on the retreating blade is reduced by the helicopter¶s forward airspeed. Therefore, as a result of the relative wind speed, the advancing blade side of the rotor disc produces more lift than the retreating blade side. This situation is defined as dissymmetry of lift. [Figure 3-14] If this condition was allowed to exist, a helicopter with a counterclockwise main rotor blade rotation would roll to the left because of the difference in lift. In reality, the main rotor blades flap and feather automatically to equalize lift across the rotor disc. Articulated rotor systems, usually with three or more blades, incorporate a horizontal hinge (flapping hinge) to allow the individual rotor blades to move, or flap up and down as they rotate. A semi rigid rotor system (two blades) utilizes a teetering hinge, which allows the blades to flap as a unit. When one blade flaps up, the other flaps down. As shown in figure 3-15, as the rotor blade reaches the advancing side of the rotor disc (A), it reaches its maximum up flap velocity. When the blade flaps upward, the angle between the chord line and the resultant relative wind decreases. This decreases the angle of attack, which reduces the amount of lift produced by the blade. At position (C) the rotor blade is now at its maximum down flapping velocity. Due to down flapping, the angle between the chord line and the resultant relative wind increases. This increases the angle of attack and thus the amount of lift produced by the blade. The combination of blade flapping and slow relative wind acting on the retreating blade normally limits the maximum forward speed of a helicopter. At a high forward speed, the retreating blade stalls because of a high angle of attack and slow relative wind speed. This situation is called.

(52) retreating blade stall and is evidenced by a nose pitch up, vibration, and a rolling tendency² usually to the left in helicopters with counterclockwise blade rotation. You can avoid retreating blade stall by not exceeding the never-exceed speed. This speed is designated *NE and is usually indicated on a placard and marked on the airspeed indicator by a red line. During aerodynamic flapping of the rotor blades as they compensate for dissymmetry of lift, the advancing blade achieves maximum up flapping displacement over the nose and maximum down flapping displacement over the tail. This causes the tip-path plane to tilt to the rear and is referred to as blowback. Figure 3-16 shows how the rotor disc was originally oriented with the front down following the initial cyclic input, but as airspeed is gained and flapping eliminates dissymmetry of lift, the front of the disc comes up, and the back of the disc goes down. This reorientation of the rotor disc changes the direction in which total rotor thrust acts so that the helicopter¶s forward speed slows, but can be corrected with cyclic input. 6. Blade flapping and coning. CONcNG In order for a helicopter to generate lift, the rotor blades must be turning. This creates a relative wind that is opposite the direction of rotor system rotation. The rotation of the rotor system creates centrifugal force (inertia), which tends to pull the blades straight outward from the main rotor hub. The faster the rotation, the greater the centrifugal force. This force gives the rotor blades their rigidity and, in turn, the strength to support the weight of the helicopter. The centrifugal force generated determines the maximum operating rotor r.p.m. due to structural limitations on the main rotor system. As a vertical takeoff is made, two major forces are acting at the same time²centrifugal force acting outward and perpendicular to the rotor mast, and lift acting upward and parallel to the mast. The result of these two forces is that the blades assume a conical path instead of remaining in the plane perpendicular to the mast. [Figure 3-4] 7. Coriolis effect. CORcOLcS EFFECV (LAW OF CONSER*AVcON OF ANGULAR ÷O÷ENVU÷) Coriolis Effect, which is sometimes referred to as conservation of angular momentum, might be compared to spinning skaters. When they extend their arms, their rotation slows down because the center of mass moves farther from the axis of rotation. When their arms are retracted, the rotation speeds up because the center of mass moves closer to the axis of rotation. When a rotor blade flaps upward, the center of mass of that blade moves closer to the axis of rotation and blade acceleration takes place in order to conserve angular momentum. Conversely, when that blade flaps downward, its center of mass moves further from the axis of rotation and blade deceleration takes place. [Figure 3-5] Keep in mind that due to coning, a rotor blade will not flap below a plane passing through the rotor hub and perpendicular to the axis of rotation. The acceleration and deceleration actions of the rotor blades are absorbed by either dampers or the blade structure itself, depending upon the design of the rotor system..

(53) Two-bladed rotor systems are normally subject to Coriolis Effect to a much lesser degree than are articulated rotor systems since the blades are generally ³under slung´ with respect to the rotor hub, and the change in the distance of the center of mass from the axis of rotation is small. [Figure 3-6] The hunting action is absorbed by the blades through bending. If a two-bladed rotor system is not ³under slung,´ it will be subject to Coriolis Effect comparable to that of a fully articulated system. 8. Translating tendency. VRANSLAVcNG VENDENCY OR DRcFV During hovering flight, a single main rotor helicopter tends to drift in the same direction as antitorque rotor thrust. This drifting tendency is called translating tendency. [Figure 3-2] To counteract this drift, one or more of the following features may be used: The main transmission is mounted so that the rotor mast is rigged for the tip-path plane to have a built in tilt opposite tail thrust, thus producing a small sideward thrust. Flight control rigging is designed so that the rotor disc is tilted slightly opposite tail rotor thrust when the cyclic is centered. The cyclic pitch control system is designed so that the rotor disc tilts slightly opposite tail rotor thrust when in a hover. Counteracting translating tendency, in a helicopter with a counterclockwise main rotor system, causes the left skid to hang lower while hovering. The opposite is true for rotor systems turning clockwise when viewed from above. 9. Translational lift. VRANSLAVcONAL LcFV Translational lift is present with any horizontal flow of air across the rotor. This increased flow is most noticeable when the airspeed reaches approximately 16 to 24 knots. As the helicopter accelerates through this speed, the rotor moves out of its vortices and is in relatively undisturbed air. The airflow is also now more horizontal, which reduces induced flow and drag with a corresponding increase in angle of attack and lift. The additional lift available at this speed is referred to as effective translational lift´ (EVL). [Figure 3-12] When a single-rotor helicopter flies through translational lift, the air flowing through the main rotor and over the tail rotor becomes less turbulent and more aerodynamically efficient. As the tail rotor efficiency improves, more thrust is produced causing the aircraft to yaw left in a counterclockwise rotor system. It will be necessary to use right torque pedal to correct for this tendency on takeoff. Also, if no corrections are made, the nose rises or pitches up, and rolls to the right. This is caused by combined effects of dissymmetry of lift and transverse flow effect, and is corrected with cyclic control..

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