US AAF TM 1-210: Elementary Flying - Pre-Solo Phase

36.     Effect of controls and straight and level flying.--a. Effect of controls.--(1) Instruction in the effect of controls should be the first lesson in flighttraining. The purpose of this phase of instruction is to familiarize the student with the effects of control pressure on the attitude of the airplane in flight. It is the student's introduction to flying.

(2) Instruction aloft should be preceded by detailed ground instruction given in simple nontechnical language to insure that the student has a clear and correct conception of the following:

Function of controls and control surfaces.

Effect of engine In power-on and power-off flying.

Correct method of using controls to secure a desired response.

Unless the student has a concrete idea as to why the airplane can oppose gravity and be controlled while in flight he is not mentally prepared to derive the maximum benefit from instruction and practice aloft.

(3) When learning the effect of the various controls, the student should avoid fixing his entire attention upon the actual movement he induces, and while observing the results of his efforts, should also attempt to be aware of the sensations which these movements arouse. Both the movement of the airplane and the resulting sensations are important as, with practice, one becomes associated with the other. The student should try the controls individually, using first only the rudder, then ailerons, and finally the elevators. When the rudder is used violently the student should note that the nose swings in the direction rudder is used and that he is thrown away from the direction of turning; when the stick is pushed forward (elevators depressed) , the nose of the airplane swings away from him and he is lifted from his seat or loses the sensation of weight; when the stick is pulled toward him (elevators raised), the nose swings toward him and he is pressed firmly in the seat; when ailerons are used, the wings swing away from him in the direction that pressure was exerted and he leans away from the bank. Although natural, this reaction should be explained and the student told to "bank" with the airplane. The student should vary the pressure on controls, noting the relative movement of the airplane and the sensations induced which will vary with the control pressures applied. Next, the student should use the controls in combination and attempt to determine which control is producing the major effect and, if adverse results are obtained, try to determine which control is causing the error.

(4) While the instructor is flying the airplane he should have the student follow him lightly on the controls. This applies to all flights. This practice, early in the course especially, will help to correct the common impression that it is necessary to use the controls violently and through a large range in order to maneuver the airplane.

 (5)  in the first flights, the altitude should be sufficiently high to prevent the student from becoming apprehensive of the ground and to make frequent assistance by the instructor unnecessary. The very fact that the student finds he is able, almost from the first, to make the airplane respond to his control without assistance is a long step toward complete confidence.

(6) Normally, acrobatics with the student are prohibited until he has had 35 hours. However, other than during the first flight, a few steep banks and chandelles will demonstrate that smooth, coordinated pressure obtains better results than rough, abrupt use of the controls. The ease with which maneuvers may be performed should be stressed.

(7) After flight, during critique, instruction and explanation relative to the scope of the next flight should be given. This flight should begin with a quick review of the work previously undertaken and practice started on straight and level flying. It will be found that students vary in aptitude even at this early state. However, progress at this time is not always indicative of aptitude.

b. Straight and level flying.--(I) The purpose of this phase of instruction is fourfold:

(a) To develop the student's control touch, alertness, and technique to the point where he can maintain straight and level flight.

(b)  To enlarge the scope of the student's perception.

(c) To improve coordination.

(d) To afford the instructor an opportunity of observing the student's reflexes and reactions.

(2) Preflight instruction should cover the correct method of maintaining straight and level flight with emphasis on--

(a) Observation of the attitude of the airplane with respect to the lateral, longitudinal, and vertical axes.

(b) Observation of the flight direction by reference to an objective on the earth, clouds, or horizon.

(c) Coordination of control pressures and the applications of those pressures only when needed.

(d)  The effect of turbulent air.

(e) The use of stabilizer controls to eliminate fatigue and improve performance.

(3) It is impossible to overemphasize the formation of correct habits of flying straight and level. Perfection will not be attained rapidly unless attention is given to the maneuver. It is not uncommon to find a student with enough time to be doing advanced maneuvers who, through failure to master this simple fundamental of straight and level flying, cannot progress.

(4) Overcontrolling, poor cockpit posture, tenseness, and fighting turbulent air constitute the problems confronting the flying instructor with the average student in this simple though fundamental maneuver.

37. Turns, gentle and medium-a. The purpose of this phase of instruction is fourfold:

(1)     To improve coordination.

(2)     To develop precision in control while changing the direction of flight.

(3)     To develop the technique of smooth flying by training in--

(a)     The gradual building up of steady control pressures as required by the degree of bank.

(b)     The steady holding of control pressures built up while the airplane is changing the degree of bank.

(c)     Relaxation or easing off of control pressures as the desired degree of bank is attained.

(4) To increase the student's ability to change the attitude of the airplane without constant attention upon the airplane itself.

b. Preflight instruction should be a simple explanation of the attitude of the airplane in various degrees of bank, that is, gentle turns up to 30°, medium turns from 30° to 45° , and steep turns above 45°; and the sequence of pressures involved in establishing, holding, and rolling out of turns smoothly.

c. From the beginning the student should be taught that the bank is merely a step toward the final goal as the experienced pilot does not consider the steepness of the bank but establishes it automatically in order to accomplish a turn in the desired direction.

d. It is essential to caution the student against a tendency on the part of many to lean away from the direction of bank. Even if the student does not press his body against the high side of the cockpit he may turn the head in order to keep the eyes level with the horizon. In primary instruction, where the student is seated behind the instructor, this fault is often overlooked until the student reaches basic instruction, by which time the habit is so deeply formed that it is difficult to break.

e. 1he probability of' skidding and slipping should be explained by showing the cause, correction, and how recognized. The student should go into the air knowing precisely what the instructor expects of him. Emphasis should be given to smoothness and precision.

f. In flight, the student's attention is diverted from the nose of the airplane by requiring turns of a specified degree such as gentle turns of 90° and medium turns of 180°. In any case during the pre-solo phase the student should not swing from bank to bank but from level to bank and bank to level, as the slight pause between turns allows the airplane to free itself from misuse of controls and usually assures a correct start on the next turn.

9. When first teaching a student to execute turns, only medium turns should be used as the control pressure in a gentle bank is so slight that the student fails to recognize it.

h. From the beginning the student must be required to check for other airplanes in the direction he intends to turn. This safety habit should be thoroughly formed before the student is considered qualified for solo flight.

i. As soon as the student has a fair conception of precision turns, he should be started on maneuvers requiring elementary application of turns such as rectangular courses and S-turns. It is excellent practice to require turns for several minutes at the beginning of each period. The practice of turns gives the instructor an opportunity to use hand signals to good advantage. When the student's troubles are slipping and skidding, the deliberate exaggeration of the error with complete explanation at the time may aid not only in identifying the error but in correcting it.

38.     Confidence maneuvers-a. Purpose-(1) The purpose of this phase of instruction is to--

(a) Demonstrate the inherent stability of the airplane with power on and off, that is, the airplane will not go out of control or appreciably change its attitude when the pilot temporarily removes hands and feet from the controls.

(b) Increase the student's confidence in the airplane.

(c) Eliminate apprehension in the student insofar as possible.

(d) Demonstrate that jerky, violent application of control pressure prevents the development of control touch and renders smooth, precise flight impossible.

(e) Impress upon the student that, when in doubt, he should relax and allow the airplane to free itself from misuse of the controls.

(2) While all flight maneuvers contribute to building confidence for the average student., certain maneuvers have been found particularly helpful. The purpose of these maneuvers, which are described later in this discussion, should be explained to the student prior to leaving the ground. The lesson to be learned from each maneuver is important and the student should be prepared in advance to appreciate the truths drawn from the demonstrations. If the maneuvers are introduced unexpectedly or without comprehensive explanation, no beneficial results will be obtained. However, if the student is forewarned, he will not be apprehensive and can obtain the confidence that is desired. The instructor, by his manner in preparing the student for the practice of these maneuvers, should continue to strike a casual note. He must inspire confidence in himself and, by so doing, will transmit confidence. Emphasis should be placed on relaxed, smooth, easy handling of the controls; that aircraft are so designed that they will of themselves, if permitted, regain and maintain more than safe flying speed when the controls are released.

b.      Description of maneuvers.--(1) Establish a bank not to exceed 45°  with varying control pressures. Remove hands and feet from the controls temporarily, placing the feet flat on the floor and holding the hands outside the cockpit where the student may see them. Require the student to hold his hands up, keeping both feet on the floor, free of the rudder pedals. During the interval of flight when the airplane is not controlled by either student or instructor, the student should note the stability of the airplane. The instructor should then take the controls and repeat the demonstration a number of times, afterward requiring the student to duplicate the maneuvers.

(2) From a banked turn, assume level flight and remove hands and feet from the controls as in (1) above and note the stability of the airplane in level flight with no pilot to guide it. The exercise described in this paragraph and the preceding one should be alternated.

(3) Pull the airplane into a stalling climb with power on. Both the student and instructor remove hands and feet from the controls and observe the stability of the airplane as it climbs to a stall. When the airplane has climbed to a partial stall, the instructor takes the controls and the airplane is eased gently out of the stall, maintaining the initial flight direction. After demonstration, the student should be required to duplicate the maneuver.

(4) Pull the airplane into a stalling climb, power on. Both instructor and student remove their hands and feet from the controls and the instructor closes the throttle. During the period the airplane is in flight without human control, it is observed for stability and reaction. Note that the airplane assumes a diving attitude, regaining flying speed unassisted. After demonstration, the student should be required to duplicate the maneuver. After completing this series of maneuvers the student should have considerable confidence in the airplane. Confidence may be considered the cornerstone upon which is built the skill of the military pilot.

39. Torque.--a. The rotational effect upon an airplane, resulting from the torque, set up by the propeller-engine combination, requires certain adjustments on the control surfaces to counteract this force. These adjustments on primary type airplanes are such that "yawing" is, normally, eliminated at cruising speeds. Yawing of the airplane will take place at less than cruising speeds with power on and at higher speeds with power on or off.

b. Inasmuch as primary type airplanes are powered by a direct drive engine, the yawing effect at less than cruising speed is to the left and conversely to the right at more than cruising speeds. From the above discussion it is seen that sufficient rudder must be applied to maintain straight flight or to avoid slipping and skidding in turns when this torque effect is present.

c. It is important that the student be thoroughly familiar with and understand the forces causing torque and resulting yawing of the airplane. A general discussion of this subject with the student should be followed by actual demonstration in the air. It is equally important that the student understand that correction for torque is not a matter of holding rudder, but that the so-called neutral position of the rudder changes as the torque effect decreases or increases.

40. Climbs and climbing turns.--a. Climbs.--(1) This maneuver should be started from a level flying position and with the throttle advanced to approximately two-thirds open. The nose is pulled up slightly above the horizon and maintained in that position. After 2 or 3 minutes of climb, level off by putting the nose back down to the horizon and retard the throttle to cruising rpm.

(2) The student must be taught to hold the correct rate of climb by feel of the proper air speed and by the position of the nose above the horizon. The greatest difficulty which students encounter in climbs is overcoming the torque. On the first day of instruction in this maneuver, the instructor should demonstrate to his students the effect of torque by holding the airplane in a normal climb straight ahead and then suddenly releasing the right rudder and allowing the nose to swing to the left.

b. Climbing turns-(2) Prior to the introduction of climbing turns, the student has had some practice in the fundamentals of flying technique. He is familiar with the climb and the turn, but these have been practiced separately. Control touch has been stressed but due to the student's limited flying experience, its need and value have not made the impression that is desired. Consequently, it is essential that, before landings are undertaken, maneuvers be introduced which, aside from their utility value, emphasize control touch and combine the climb and turn.

(2) As a training maneuver, rate of climb, rate of turn, and constant angle of bank should be stressed but only in the sense that their accomplishment is the result of light, controlled pressures which effect and maintain the desired attitude.

(3) During climbing turns, a shallow bank should be maintained, and since both climb and turn are slow, the student is able to devote more attention to control pressures and less attention to the nose of the airplane.

(4) In addition to the foregoing, the maneuver aids in preventing aerial collisions, as turning constantly clears the area forward of the airplane and permits approaching aircraft to be observed and avoided.. Practice of this maneuver will also help develop the ability to hold an even turn with some semblance of ease and consequently improve all of the student's flying.

(5) Common faults are:

(a)     Using positive movements of the controls rather than even pressures.

(b)     Too much opposing pressure on the aileron and rudder. This action tends to reduce the bank and slow the turn. It is very noticeable to the instructor as it gives him a desire to shift his position to the high side of the bank. It may be corrected by requiring the student to relax definitely on the conttrols after establishing the turn and then use light, corrective efforts.

(c) Climbing and turning too steeply. This is a normal reaction providing it is not exaggerated and responds to correction.

Note-Later in his flying training, if the student becomes rough and abrupt in the use of the controls, it will help to smooth up his control touch if he will devote the major portion of a solo period to practicing climbing turns and gliding turns.

41. Glides and gliding turns.--a. Glides--(1) While gliding in for landings in the earlier lessons, the instructor should have called the student's attention to the attitude of the airplane and the relationship of the pitch of the sounds incident to gliding, to attitude and speed. He should have attempted to fix in the student's mind the correct angle, and its corresponding sound and feel, to be assumed for a normal glide. Also, when leveling off and landing, the decrease in pitch of the sound as the speed is decreased should have been called to his attention and the relationship established. However, even though the student is allowed to follow through on the controls during these operations, the control touch during the glides and landings will be strange until he is given the controls completely. This early instruction in the relationship of angle, speed, and sound will nevertheless facilitate greatly the comprehension of instruction when glides and landings are undertaken.

(2) One of the demonstrations during the "confidence maneuvers" was to allow the airplane to assume its own attitude without power and without interference. In the explanation accompanying this, the instructor pointed out the necessity for back pressure on the stick during the glide. This should be reexplained and the student shown also that since this diving tendency is constant, back pressure must be held constantly in order to hold the desired angle and speed.

(3)     Initial instruction in glides should be given at an altitude of at least 2,000 feet and combined with instruction in climbs. The throttle should be eased back and the airplane eased into a glide until the proper angle is established. When this angle has been assumed, the instructor should so indicate to the student and require him to hold it while he again explains the necessity for fixing in his memory the angle, speeds sound, and feel of the controls of the airplane.

(4) Abnormal glides should not be demonstrated until the student has grasped the fundamentals of the normal glide or confusion will result, since the ,student will have no basis for comparison in recognizing his errors and correcting them.

(5)     Due to lack of experience, the student will be unable to recognize slight variations of speed and angle of bank immediately by vision or by the pressure required on the controls. Hearing probably will be the indicator that will be used most easily at first. The instructor, therefore, should be certain that the student understands that an increase in the pitch of sound denotes more speed, while a decrease in the pitch denotes less speed. When the student receives such an indication, he should consciously apply both other means of perception so as to establish how they deviate from the correct. In this way he will fix the correct relationship more firmly in his mind and increase the sensitivity of his perceptions.

(6) If this is not done, the student may be able to "get by" after a fashion but he never will develop the proper sensitivity to the stimuli or awareness of what is going on. The goal to be sought is suconscious correction for the slightest deviation before any visual evidence of change is noticeable.

(7) As soon as a good comprehension of the normal glide is attained, the student should be shown abnormal glides. These demonstrations should be exaggerated for the benefit of the limited perceptiveness of the student. In demonstrating too slow a glide, the airplane should be mushed and the student's attention called to the sluggishness of the controls, the extra pressures required to hold the nose, and the definite feeling that the aircraft is falling out from under him. It then should be stressed that, although this is an exaggerated condition, any time the speed is below that of a normal glide the pilot does not have complete control of the airplane and that these same conditions exist, the difference being merely in the degree of their existence.

(8) Too fast a glide should then be demonstrated, ending with the airplane being brought to level flight and allowed to coast level until normal gliding speed is regained and then the normal gliding attitude resumed. The instructor should have the student note that although good control is maintained, excess speed is acquired which is hard to dissipate and results in extended floating. He should explain that when this condition exists close to the ground  it is exaggerated, oftentimes, by the ground cushion of air and will absolutely destroy any efforts toward accuracy in landing.

(9) In a normal glide, the flight path may be sighted to the spot on the ground on which the airplane will land. This cannot be done in any abnormal glide. In the early stages of glide instruction, it may be necessary in some airplanes to have the student force the airplane into the gliding attitude as a safety precaution. However, as experience is acquired, this should not be done.

(10) Too few instructors pay proper attention to fixing the normal glide in the student's mind together with the results of abnormal glides. As a consequence, students experience difficulties with accuracy landings, which are comparatively simple if the fundamentals of the glide are understood thoroughly.

b  Gliding turns.--(1) Gliding turns are particularly important in a student's training. Since they are directly related to accuracy landings, as will be seen in later discussions., they almost always are used for some practical purpose. Therefore, it is necessary that they be executed more subconsciously than other maneuvers since most of the time during their execution the pilot will be bringing his attention to details other than the mechanics of making the turn.

(2) Since they are used close to the ground more than any other maneuver, the accuracy of their execution and the formation of proper technique and habits are of especial importance.

(3) It is then evident that the perfection of these maneuvers is of the utmost importance to the student, and since the action of the control system is somewhat different in a glide than with power, gliding maneuvers stand in a class by themselves and require the perfection of a special technique beyond that required for ordinary-power maneuvers.

(4)     This control difference is caused in the main by two factors:

(a)     Absence of the usual slip stream.

(b) Difference of relative effectiveness of the various control surfaces at various speeds and particularly at reduced speed. (This will be noted more particularly during the practice of stalls.) This last factor has its effect exaggerated by the first and makes the task of coordination even more difficult to the inexperienced student.

(5) These principles should be explained thoroughly to the student in order that he may be alert to grasp the difference in coordination necessary. After he has developed the feel of the airplane and the control touch, this compensation will be automatic; but while any mechanical tendency exists in his coordination, he will have difficulty in executing gliding turns, particularly when making a practical application of them in attempting accuracy landings.

(6)  Three elements in gliding turns which tend to force the nose down and increase gliding speed are--

(a) Decrease in lift due to the direction of the lifting force being at an angle to the pull of gravity.

(6)  Use of the rudder the same as in a power turn.

(c) Normal stability and inherent characteristic of all well-designed airplanes to nose down when the power is off.

These three factors make more back pressure on the stick necessary than in the case for a straight glide or a power turn and therefore affect even more the normal relationship of control coordination.

(7) When recovery is being made from a gliding turn, the compensating relaxation of this back pressure must be increased or the nose will come up too high and considerable speed will be lost. This error will result in considerable attention and conscious control adjustment being required before the normal glide can again be resumed.

(8) Since these elements mentioned above reduce speed of airplane and reduce lift in normal power turns, it is readily seen that more speed and more lift will be lost in a gliding turn of equal degree of bank for the following reasons:

(a) Due to the reduced speed of the airplane in a glide, any further reduction will cause a greater corresponding proportionate reduction in lift.

(b) The increased back pressure necessary on the elevators causes more drag and consequently loss of speed.

(c) Since centrifugal force must be used to equalize the difference in the direction of the lifting force when the airplane is off an even keel, some energy or power must be used to obtain it. Since the engine is throttled back, this can come only from gravity. This will therefore require either a steeper gliding angle to maintain normal speed, or a reduction of the normal speed with its consequent mushing and approach to a stall.

(9) From the above it will be seen that, in order to maintain the most efficient or normal glide, more altitude must be sacrificed than normally since this is the only way speed may be obtained without power. It is apparent, therefore, that the gliding angle will necessarily be steeper to maintain the same speed and lift as in the straight glide, and that the turn in a glide decreases the efficiency of the performance of the airplane to an even greater extent than does a normal turn with power. This is a principle that must be thoroughly explained and impressed on the student, as it will furnish a basis for understanding many of the errors he will make and is a principle that few will learn through their own efforts at error analysis.

(10) From the above it will be seen that the student must learn still a different set of  relationships of control touch, angle of glide, and sound for gliding turns to maintain the same speed and lift as in normal straight glides. These will vary again with the degree of bank; therefore, the student should confine his early efforts to one angle of bank (again preferably the medium) , and the instructor insist on its constant maintenance until enough background and feel is attained to give appreciation of the shading of pressures necessary for gliding turns of varied or varying steepness of bank.

(11) After the desired degree of bank to be used during the early practice has been fixed in the student's mind, he should be shown the undesirable results of too much speed and too little speed, as explained in the discussion of straight glides.

(12) Another factor that affects the more or less mechanical student during the practice of gliding turns is the decrease in the overbanking tendency in turns without power. If the same effort is applied to oppose these tendencies as has been customary in power turns, the bank will decrease. The inexperienced student will not sense this and attempt to increase the rate of turn to that anticipated by applying more rudder, which will soon result in a flat skid.

(13) In the recovery from a gliding turn, the rudder action is, of course, practically the same as in a power turn, but the pressure required is much less. Hence, even though the action of the rudder is the same, it seems to be different because the resistance to pressure is so much less due to the absence of the slip stream. The net result, then, is a much greater application through a greater range than is realized by the student; and as a result, the turn seems to 'stop immediately when the rudder is applied in recovering. This. last factor, particularly, is important during landing practice since the student almost invariably starts to recover too soon and either will come in cross wind or try to force the ship into the wind with the rudder alone. This results in the landing being made in a skid that is too easily and too often mistaken for drift, thus confusing the student who can see that something is wrong but is at a loss for the reason. When this happens, he is too occupied to give his attention to making the landing, and a bad landing results. If he does not notice it, as often is the case, he lands in the skid. Instructors too often fail to realize this factor and either accuse the student of using too much rudder or of landing cross wind, when actually the real cause is the premature starting of the recovery from the gliding turn.

(14) Particular attention must be paid to the action of the nose in entering and recovering from gliding turns. As in all other turns, it must not be allowed to describe arcs with relation to the horizon and particularly it must not be allowed to come up during recovery or during the exercise of rolling from one bank to the other when alternating the turns. This exercise should be practiced in all turning maneuvers since it not only insures equal practice of the maneuver both to the right and to the left, but is also one of the best means of perfecting coordination, if executed slowly and smoothly. This particularly is true in climbing and gliding turns since they require a constant variation of the relative pressures on the different controls.

(15) Time devoted to glides and gliding turns, other than that ordinarily obtained during landing practice, is particularly important when landings are begun and as an additional exercise during landing practice, since the landings will be no better than the glides. Poor glides and gliding turns invariably result in poor landings.

(16)    During the entire training period and particularly during gliding work, it should be impressed upon the student that he must not think of control movement. He must be taught to think in terms of movement of the airplane. In other words, by exerting certain pressures he moves the airplane in the desired fashion. This must be instilled in him until the airplane practically becomes a part of him, controlled by subconscious muscular reaction to his wishes. An example of this is the manner in which the fingers ordinarily are used in picking up an object. No conscious thought is given to directing the action of the fingers; their actions are automatic and only the incidental result of a desire to examine the object that attracts the attention.

C. Spirals.--(1) Definition-A spiral is simply a steep gliding turn, maintained through several revolutions.

(2) Purpose.-The chief value of this maneuver is in improving power-off turns, teaching orientation, and eliminating possible tendencies in the student toward vertigo or dizziness. The practice of spirals also aids in the teaching of normal recovery from steep gliding turns and corrects the faults of stalling or diving out of such a turn--dangerous errors close to the ground.

(3) Execution.--Considerable altitude must be obtained before starting this maneuver in order that the spiral may be continued through a long series of turns, since it will be found that the student probably will exhibit no difficulty in the first two or three turns. It is only when it is prolonged that the student is prone to let the ship get away from him, become dizzy, or lose his sense of position. This maneuver should not be continued below 1,000 feet. No judgment of drift or altitude is necessary at first, except to see that the recovery altitude is sufficiently high, later, a ground object should be used as a center and due allowance made for drift. The objectives are a constant gliding speed and maintenance of a predetermined position.

42. "S" across roads (fig. 2).--a. General-The first few hours of the student's flying training have been devoted to practicing turns and straight and level flight, with the objective of starting the development of habits of coordination and timing, which are essential to proper handling of the controls of the airplane. Unless he has had prior flying experience, due to necessity, his attention has been confined solely to the airplane, that is, its relation to the horizon and his efforts upon the controls. If permitted, this concentration of attention would become a habit, and a bad one, just as deeply fixed as any other bad habit he may have formed. Therefore, just as soon as he shows some proficiency in the mechanics of turning, it is necessary that he be placed on some very minor problems of application. Additional and more difficult ones should be added as he indicates the ability to advance. The time to introduce such maneuvers is when the student is able to-

(1) A Within reason, coordinate his efforts upon the controls in the manner required for turns..

(2) Within reasonable limits, maintain altitude while going into, while in, and during recovery from turns.

(3) Have some conception of his relationship to objects upon the ground,

(4) Estimate a safe climb.

(5) Differentiate between a dive and a slight variation from level flight,

. b. Purpose-The "S" across roads is a maneuver involving very elementary application of turns and generally is the first one of this type undertaken.  Its elementary performance does not require much ability and neither does it distract too much of the student's attention from the airplane.

c. Requirements.--(1) Ground objects-Road, fence line, hedge, or similar prominent landmark which may easily be observed from the air and whose general line is straight for a distance of approximately 1 Mile. A longer distance is desirable, and a much shorter one will complicate the maneuver.

(2) Altitude-The altitude should be 500 feet. the same as that used for traffic around landing fields, with the purpose of' developing the student's perception of' a specific altitude and one which will help him when landings are undertaken.

(3) Bank-Within the range in which the student has had experience, the "S" across roads is a maneuver which may be used throughout the course to advantage, varying the steepness of the bank according to the student's progress.

d. Procedure-(1) While in straight and level flight at 500 feet, cross the road at an angle of  approximately 90° to its general line. As soon as the road is crossed, start the turn in the direction it is desired to travel and maintain the turn. Plan while recovery so as to be heading at an angle of 90° to the road and permit straight and level flight for a short interval just prior to, and after crossing it. Repeat the process until the end of the road is reached and if by that time insufficient practice has been obtained, reverse the direction of turning and adjust flight to permit traveling back down the road.

(2) The maneuver is flexible and is not governed by any set rules. The foregoing procedure is merely one of many types. However. if the road is crossed at an angle of much less than 45°, straight and level flight can be maintained but momentarily and the maneuver becomes a series of short, choppy turns or in effect is nothing but one of the phases of the confidence maneuvers. Under this last condition the student is apt to concentrate too intently upon the airplane. He is unable to estimate or correct for drift or obtain a conception of radius of turn, and most of the intent of the maneuver is lost and it ceases to have any step-up value.

Note.--Each maneuver should embody some of the principles of the succeeding one, or should have some step-up value.

e. Compensation for drift.--To compensate for drift during "S" across roads or various types of eights:

(1) On upwind side--Start with a shallow turn and steepen when sufficient ground distance has been gained to permit completing the maneuver. The shallow turn will give a greater or larger radius of turn and consequently lengthen the track upon the ground and make distance into the wind.

(2) on downwind side-Start with a steep turn and decrease its steepness when sufficient ground has been gained to complete the maneuver. The steep turn gives a shorter or smaller radius of turn and thus permits control of the amount of drift.

f. Common faults.--(2) usual errors in turns, that is, tenseness, poor coordination, and failing to maintain altitude.

(2)     Poor timing of start of turn and recovery from turn.

(3)     Failing to correct for drift,

(4)     Errors in straight and level flight,

43. Rectangular courses (fig. 3) . -- a. General. - Practice in the 'IS" across roads has given the student some practice in turning and planning his flight in relation to ground objects. Preliminary practice has also included definite changes in direction through angles of 90° , 180° , and 360°. However, before landings are started, he should have some experience in a maneuver which simulates the flight path required around a landing field or otherwise when these are undertaken he must learn to accommodate himself not only to flying a prescribed course but many other things as well. Obviously, if too many things are undertaken at once, especially during landing practice, it not only confuses the student but adds to the difficulties of traffic which, at best, is congested at the time when every effort is being made to solo as many as possible.

b. Purpose-Rectangular courses are included in the program of flying training in order to afford the student an opportunity to accustom himself to flying in relation to a definite ground course and at the same time maintain altitude. The maneuver not only simulates conditions encountered during landing practice but has the following useful purposes:

(1) Application of turns.

(2) Dividing attention between ground objects and the airplane.

(3) Practice in timing the start of turn so as to permit the turn to be fully established at a definite point on the ground.

(4) Practice in timing the recovery from a turn so as to permit flying in definite relation to an established ground course.

(5) Practice in establishing track or determining "crab" angle.

c. Requirements-(1) Ground-Field, woods, or similar landmarks whose general outline is rectangular, easily observed from the air, and is approximatly one-fourth mile on the shortest leg.

(2)Altitude.--Five hundred feet.

(3) Bank.--Within the range of the student's experience.

(4) Flight path.--(a) Do not attempt to fly over the actual perimeter of the rectangular course or, in other words, do not attempt to place the fuselage directly over the ground landmarks outlining the course. This is not only difficult to do but has the following disadvantages:

1. Turns must be very steep or, if made within the range of the student's experience, the flight path ceases to be rectangular and becomes a circle inscribed within the rectangle.

2. Requires an exceedingly large field or similar outline and thus limits the number of available courses.

3. Turning point is lost and the student must guess where to start and recover from a turn. This will cause considerable jockeying and promotes overcontrolling at a time when smoothness and precision must be developing.

(b) If the field is small, then the flight path should be so conducted that the outline of the field appears to be slightly outside the wings on the side toward the course.

(c) The distance flown to one side affects the steepness of the bank used since turns must be made steeper as the flight path approaches closer to the actual outline of the course. When the outline appears to "cut" the wings at a point about midway to the fuselage, the bank of the turn will be approximately 45°.

d. Procedure-(1) Approach the field at 500 feet and parallel to one side. Time start of turn in order to permit maximum bank at the corner of the field. Time recovery from turn so as to permit flying parallel to the adjacent side. After flying around the field a few times in one direction, the direction of travel should be reversed.

(2) The maneuver may be made more complicated if prior to its execution, the student is directed to make a certain number of complete trips in one direction, then a certain number in the opposite direction, and, when he believes that he has completed the requirements, to leave the vicinity of the field. This version of the maneuver will require some concentration in order to keep track of the number of completed trips and involves some planning when he attempts to reverse his direction of travel.

(3) The maneuver may be further complicated and at the same time afford useful practice if the student is required to retard throttle along one leg, establish glide, execute turn in glide, recover from turn in glide so as to be flying along the adjacent leg, open throttle, establish climb, turn out from the field in order to meet the requirements of the normal rectangular course, and obtain sufficient altitude so that the same procedure may be followed at the opposite corner of the field.

(4) This adaption will require a fairly large rectangular course and it is practically impossible to repeat the procedure more than twice during one complete trip. However, its advantages are manifest and it will aid the student when similar conditions are met during landing practice.

(5) Explanations should be amplified by blackboard sketches and the maneuver demonstrated before the student attempts it.

Common errors.--(1) Usual errors in turns, such as tenseness, poor coordination, and gaining or losing attitude,

(2) Improperly timing the start and recovery of the turn,

(3) Losing course when it is necessary to leave it in order to reverse direction of travel.

(4) Failing to allow for drift, or not establishing "crab" course.

(5) Losing count of completed trips.

(6) Poor planning.

Note--The sole purpose or all elementary maneuvers, such as the "S" across roads and the rectangular course is to prepare the student to solo. It should be borne in mind that the more practice the student can obtain under simulated conditions, always keeping the time element in mind,. the easier it will be to teach landings as then the student can devote the major portion of his attention to the major mission-landing and taking off. Experience has taught that the actual process of landings comparatively simple providing instruction does not involve all of the phases of the trip around the landing course.

44. Stalls, power on and off-a. For training purposes, stalling should be considered as a loss of speed to the extent that it lessens proper control of' the airplane although the term is customarily used to describe the condition at which speed has been so reduced as to cause the controls to be practically ineffective.

b. Effective control, assuming properly designed control surfaces, normal stability, and similar factors are dependent upon the forward speed of the airplane being above a rather definitely established minimum for the type. However, any design features should not be the only consideration, as practical flying requires that the pilot know how rapidly controllability falls off during a further slight reduction in speed. This critical speed is the deciding factor and determines the degree of impunity with which the airplane may be flown at low speeds. Operating at low flying speeds is not necessarily dangerous, but it is dangerous to operate at or near the critical speed unless the pilot is aware of it, is alert, and can give the major portion of his attention to flying the airplane.

c. One of the most important objectives of flying training is to develop an awareness of the approach to stalling speeds, or of the speeds at which the controls become relatively ineffective. Fundamentally, vision is the most important. sense used. However other supplementary senses should be developed, to indicate approach to stalling speeds in order to permit sight to be used for purposes other than continually checking the attitude of the airplane. In other words, insofar as possible, vision should have the role of checking or verifying when stalling is indicated through other senses.

d.      The use of the major senses is noted in the following:

(1) Vision-Visually, in most instances, a stall is an attitude in which the nose of the airplane is carried higher than it should be for the speed and power developed.

(2) Hearing.--As speed decreases, the noises incident to flight diminish in pitch and intensity; if the engine is used, it labors and the loss of rpm is audible; vibratory noises increase. All of these are noticeable, the degree depending upon the magnitude of the stall.

(3) Kinesthetic, or muscle and tenson sensitivity. As speed is lost, a proportionate loss in resistance to control movements can be noted as well as a greater lag between change in control pressure and the response of the airplane. As speed is  further reduced, the resistance to control pressure becomes less, movements of the control surfaces must be of larger amplitude in order to obtain even mediocre results, and the lag between pressure and response becomes greater. When completely stalled, all responses to the controls will cease; they may be moved through extreme ranges and not produce results.

e. From the foregoing it may be seen that no one sense plays a full part in the detection of stalling speeds and, with training, each supplements another.

.During the early phases, sight is practically the only means whereby the student is able to note stalling as other sensory aids ate in the process of development. However   this condition should not exist for too great a period as visual flying (as opposed to Instrument) requires that all be used.

1. All stalls require either altitude or additional power to regain sufficient speed for recovery.  The more severe the stalling, the more altitude or power is required. The longer it takes to detect the approach of stalling speeds, the more severe the final stall will be. For this reason, during early training it is essential to err on the side of requiring slightly more speed than is absolutely necessary for the performance of a maneuver. Later, when more experience has been gained, the same maneuver may be performed at a safe minimum speed.

g. Spins result from exaggerated stalls so in order to prevent accidental spins more attention needs to be given to stalls. Recovery from spins is an important part of the student's training but the dangerous spin or stall is the one that occurs at too low an altitude to allow recovery no matter how well trained the pilot is in that phase of the maneuver.

Prior to solo all students are given definite practice in recovery from spins, but during early solo flights (first few solos) ability to recover will not suffice as it is seldom that there will be sufficient altitude to allow for losses due to the stall which precedes spinning and still leave enough to permit recovery from the spin. During the early period of training, time and care devoted to stalls are far more important than that on spins.

h. Controls normally become effective in the following order: rudder--permitting taxiing at relatively low speeds; elevators--raising the tail for the take-offs; and ailerons--not usually effective until considerable speed has been developed. As speed is lost they become ineffective in the reverse order, that is, ailerons. elevators, and rudder. The order of comparative strength named is not a hard and fast rule but it is reliable enough to be of great aid when difficulties are experienced during, acrobatics, as frequently a check will reveal that, at low speeds, a major control has been used first arid thus prevented a weaker one from becoming effective.

 i. The following includes specific instruction in stalls and some of the salient points to be covered:

(1) Execution, power on-At a safe altitude, from level flight ease back upon the stick until further efforts on this control not only fail to obtain any response but actually cause the nose of the airplane to fall slightly. To demonstrate the lack of effective control when fully stalled, move all controls through their maximum ranges arid require the student to note the comparative lack of response to their use. At this time demonstrate that it is impossible to maintain either the attitude or the altitude for any appreciable period and that attempts to do so only aggravate the stall, with resulting excessive loss of altitude, and no control of the falling attitude during recovery. During recovery, use all controls in the manner which forces the airplane to fall straight ahead, wings level. Require the student to repeat the maneuver several times, slowly, so as to permit him to recognize the various sensory indications of loss of speed. Vary practice in straight stalls by pulling up similarly as in the start of a chandelle and stalling the airplane in this position.. During recovery, force the airplane to fall straight ahead, wings level, emphasizing the use of ailerons and rudder to obtain the effect desired. Require the student to repeat the maneuver and stress that recovery should be made in a level attitude.

(2) Execution, power off-From level flight, throttle fully retarded, ease back upon the stick until all responses cease. Demonstrate the lack of control as in the foregoing. Require the student to repeat the maneuver. If the elevators are used before dissipating the excess speed of cruising over gliding, the nose of the airplane will rise, similarly as in power-on stalls but to a lesser degree. If the cruising speed is dissipated before using the elevators, the nose will rise but little and the stall will occur in a more or less horizontal plane. This latter type has the advantage of' being a departure from the normal stall in that the nose of the airplane is not above the horizon.

j. Once having been demonstrated, and the student permitted to learn for himself that it is impossible to hold the airplane in the air by means of the controls alone, it is a waste of time to practice full stalls. Practice should be concentrated on partial stalls which permit the development of ability to detect loss of speed and yet riot sacrifice complete loss of control. Obviously, it would be poor training if the student's conception of loss of speed included only that condition when all control was lost and this, unquestionably, would be the case if his practice consisted in going from full control to no control without regard to any loss of speed or control during the transition.

k. it should be demonstrated that the spin usually requires complete stalling plus the use of full rudder arid elevator. Spins in primary type airplanes will not result, even at low speeds, unless control movements are exaggerated.

1. It is extremely important that the student be taught to recover from stalls with smooth though positive use of controls. Sudden and jerky use of elevators in attempting to recover from a stall even with the plane in a gliding or diving attitude may aggravate the stall and cause still further loss of altitude before recovery can be made. During recovery from stalls use the controls smoothly but positively, as opposed to roughly and abruptly, and in the manner that will produce results. This principle should be applied not only to stalls but in the performance of all maneuvers. It should be emphasized that at low speeds it requires large control movements to obtain any results but if they are used sharply as well as through great ranges, each one so used acts as an air brake and further reduces any remaining speed. Do not attempt to recover from the dive at the moment the nose of the airplane falls below the horizon but At that point, if a tentative effort upon the elevators does not obtain positive results, relax and wait until sufficient speed has been regained so that there will not be too great a lag between control efforts and airplane responses. Any attempts to recover too soon will result in the loss of more altitude than necessary and cause the student to form the bad habit of attempting a maneuver when he has insufficient speed with which to accomplish it.

M. Practice in stalls furnishes an excellent opportunity to further the development of control feel. Stalls are also of great aid in bringing out the saving action of "When in doubt, relax and give the airplane an opportunity to vindicate its inherent stability."

n.      Common errors are--

(1) Tenseness.

(2) Watching the nose of the airplane too intently.

(3) Using insufficient control during recovery, especially of the rudder, to force the airplane to fall straight ahead, wings level. Incidentally, some instructors, when their students have had difficulty in maintaining straight flight on the take-off, have taken them in the air and had them practice recovering from stalls along a road, emphasizing that the recovery should be made parallel to it. The object, of course, is to demonstrate that at low speeds it requires large and positive movements of the controls

(4) Attempting to hold the airplane in the air long after all controlling speed has been lost.

(5) Rough and abrupt use of controls during recovery.

o. For emphasis, the ability to recover from spins is important but it is far more important to develop the ability to detect and correct for loss of speed, which is preliminary to spinning.

45. Taxiing-a. Many minor accidents can be traced directly to the student's inability to taxi correctly. It should be explained to the student that the direction of the airplane's travel while on the ground is controlled by means of the rudder, and he should be required to obtain positive directional control of the airplane before any attempt is made to teach landings, A good exercise to teach directional control is to taxi at varying speeds and require the student to change the direction several degrees to the right and left upon signal from the instructor in taxiing on the field or while coming into the line, the student should be required to check the area ahead by turning the airplane rather than trying to look over the side.

b. Unless the field is soft or rough, it is best to taxi with the stick relaxed (elevators neutral) or slightly to the rear. On a soft or rough field the stick should be held back sufficiently to retain a safe margin of control. When taxiing down wind, if the wind is of considerable velocity and especially if the airplane is light, it is necessary to hold the stick well forward (elevators down), the amount depending upon the velocity of the wind. Taxiing into the wind is more easily accomplished since the forces causing involuntary turning are absent.

c. Since the propeller blast plays an effective part, especially in taxiing without brakes, proper handling of the throttle is one of the first requisites of taxiing. Short blasts from the propeller are an aid in turning but the student should be discouraged from the first in attempting to turn the plane without the help of a man on the wing tip unless the radius available for the turn is more than the required minimum. While taxiing for considerable distance, the throttle should be set so as to give a reasonable and safe speed and should be varied as little as possible,

d. Loss of control while taxiing (ground looping) may result unless the speed is slow before attempting a change of direction, especially into the wind. The speed at which taxiing can be safely accomplished is determined by experience but the instructor should insist that it be well below maximum. Control is the main objective; that is, to be able to stop when and where desired, and to be able to turn when and in the manner required. In general, the speed depends upon the condition of the surface of the field, the proximity of other airplanes, and the experience and judgment of the student. The approved procedure for taxiing when in the proximity of other airplanes or obstacles is to apply slight brake pressure and to taxi at a reduced rate of speed with the engine pulling against and overcoming the brake pressures. Employment of this technique will materially reduce the tendency to "nose up" caused by sudden application of the brakes, the so-called slack having been previously removed. Furthermore, with application of slightly more brake pressure, the airplane can be stopped promptly at any desired point.

e. Students should be taught to use the brakes and allowed to use them when necessary. Lack of familiarity with the pressures required to operate airplane brakes may result in an accident when brakes are suddenly applied in an emergency.

46. Take-offs.--a. General.--Each type of airplane will have a theoretical take-off attitude, which is best suited to develop speed and lift and assure the quickest departure from the ground. However, under practical conditions, this ideal may be approached but rarely attained, as it is seldom that the takeoff surface is perfectly smooth. In general, practical flying requires that the take-off be made to fit the field somewhat more than to fit the characteristics of the airplane.

b. Use of throttle.--Peculiarities in take-off characteristics are developed or accentuated in proportion to the rapidity with which the throttle is opened or full power developed. Consequently, proper use of the throttle is the first requisite which insures a smooth, straight, controlled take-off.

c. Control of airplane.--Resistance to movements of the controls, coupled with the response of the airplane to such movements, is an indication of the pilot's degree of control of the airplane. This resistance is not a measure of flying speed in terms of miles per hour but only in the sense of controllability. It is possible to move the controls so rapidly and forcibly that this resistance will not be noted or appreciated. When this is done, the pilot must wait for the response of the airplane before he has a very intelligent idea of what next to do.

d. Effects of speed on controls.--The context of the preceding paragraph must be considered when instructing in take-offs as at no time during the maneuver is the speed of the airplane commensurate with that to which the student is accustomed. Consequently, he will tend to move the controls through large ranges as he meets no appreciable resistance to his efforts. As a result, response of the airplane is delayed and occurs long after efforts have been exerted. This will tend to cause the student to over control unless considerable emphasis is placed upon ease and feel. He should be advised to feel lightly for the resistance to his efforts and, by bearing against it, accomplish the desired results. With this conception, with practice and experience, he will develop the perception which will enable him to determine when sufficient speed has been developed to assure a normal take-off, rather than merely to guess at it.

e. Brakes.--Brakes have added to the ground controllability of the airplane but, except in an emergency, they should not be used during the take-off Brakes have materially reduced the difficulties of primary training. Accidents due directly to improper use of brakes are very infrequent and with normal care and proper instruction, no trouble will be encountered in the use of this control.

f.      Take-off technique on soft fields.--If the field is soft, the take-off attitude should be such that the line of thrust makes a slight angle away from the ground. The tail wheel should be raised from the ground in order to prevent this structure from ploughing through the soft surface and adding to the resistance which must be overcome by the engine, but not raised to the extent that is required for a normal take-off.

g. Taking off-When taxiing into position for the take-off, the student should taxi along a line more or less at right angles to the direction of taking off. If this distance is greater than a few feet, he should "S" in order to see if his path of travel is clear. During the early part of his approach he should observe not only ahead but in the direction from which other airplanes may be coming in to land (to avoid being landed upon). As he approaches the line of take-off, he should observe in the direction that take-off is contemplated so as to insure that he has a clear line of flight and sufficient take-off area. The airplane should then be stopped between 45° and 90° to the direction of take-off and the areas to the rear and front checked for airplanes or obstacles. After both his rear and front areas have been checked, the student should straighten the airplane into the take-off direction, pause momentarily, and proceed as follows:

(1) Open the throttle just sufficiently to overcome the inertia of the airplane and cause it to roll slowly,

(2) Then fully open the throttle, using a smooth, unhurried effort.

(3) Maintain direction upon the ground no matter how much effort is required upon the rudder.

(4) After the throttle is fully opened, ease the stick forward until resistance is felt and then exert pressure against this resistance until the tail is raised and the airplane appears to be in the approximate attitude it assumes when in a shallow climb.

(5) When desired attitude is assumed, relax upon the elevators.

(6) Then exert a light, tentative effort back upon the elevators and, if resistance is felt, continue this backward movement with a slow, firm pressure such that the tail is not lowered but the weight of the airplane feels to be upon the stick.

(7) Attempt to determine the instant the airplane leaves the ground and then establish a shallow climb.

Note-Do not attempt to force the airplane from the ground, as this tends to delay the take-off and cause the initial climb to be too steep.

h. Value of proper instruction.--Other than tenseness and apprehensiveness, most of the difficulties encountered are due to opening the throttle too rapidly and at the same time attempting to raise the tail of the airplane. By attempting the execution of too many unfamiliar things at once, he does none of them well. Corrections and guidance in this respect will assure normal success. More latitude in the procedure may be permitted as the student develops proficiency.

i. Take-offs cross wind.--(1) General-Although take-off's should be made into the wind whenever possible, if instruction is given in a narrow field, it frequently becomes necessary to make cross-wind take-offs. Unless the wind is quite strong, these present no serious problem. There is, of course, a tendency to weathercock, which has been discussed thoroughly under taxiing. This tendency becomes less and less as the speed increases and the controls become more effective. There is also a tendency for the ship to drift sideways as it begins to bounce just prior to taking off. This imposes severe abuse on the landing gear and connecting parts of the structure.

(2) Execution-(a) The take-off should be started in the normal manner, using extreme care to maintain a straight course by use of the rudder. The tail should be lifted as quickly as possible and raised somewhat higher than in a normal take-off, so as to acquire ample speed on the ground and eliminate bouncing as much as possible.

(b) As the speed approaches that of flight, a slight pressure should be exerted on the stick toward the windward side. This pressure should be maintained as the ship gets into the air so as to counteract drift. It is desirable to gain sufficient excess speed before taking off so that the ship may be definitely "pulled off" without danger of its settling back on the ground. It then should be carefully leveled off, and as soon as climbing speed has been acquired, drift correction should be applied.

(c) One thing that may be confusing to the beginner is that, in this maneuver, rudder and aileron are used in opposite directions; that is, if the wind is blowing from the right side, left rudder must be applied to keep the ship from swinging into the wind, but the stick is pressed to the right so as to depress the windward wing.

47. Landings-a. General.--(1) The practice which has been devoted to stalls, as well as the instruction received in glides, will prove of great benefit to the student in the practice of landing. Having followed the instructor through on landings since the initial flights, he will have some idea of the process and the sounds, with reference to the relative attitudes of the airplane incident to a landing. A landing is nothing more than a very slow, mushing, stall started about 10 Feet above the ground and progressively increased and continued as altitude is lost until the complete stall occurs just as the wheels and tail touch the ground, or preferably just an instant before.

(2) Before initial landing practice is begun, the student should be seated in the airplane while the ship is on the ground and his attention called to the position of the nose with respect to the horizon and the attitude of the airplane with respect to the ground.

(3) During the foregoing periods, when the student has been allowed to follow through only, he naturally will ask questions regarding. the technique of landing, especially when his attention is called to the sensations he experiences. All the factors should be explained to him before actual practice is to start, since this will prevent the formation of erroneous ideas and their resultant bad habits.

(4) (a) When a number of students start their training together and take their instruction at approximately the same rate, it will be natural for some rivalries to develop. These increase when landings are started and great care must be exercised that the apt students do not get "cocky" nor the slow students discouraged. The slower student, particularly, will redouble his efforts in an attempt to catch up and, as a consequence, double his errors, which further delay his progress.

(b) Often an instructor will make the mistake of starting landings too soon with such a student in an effort to force progress or as a means of building up his morale.. When this is done, the results invariably are bad. The student is not ready and consequently makes more errors and has more difficulties, while morale gets lower and lower.

(c) Congested traffic plays havoc with the student who is not ready to cope with such conditions, by distracting attention sorely needed for the work he is attempting. This also results in the instructor frequently being forced to interrupt the student and take full charge as a safety measure, which further confuses and discourages such a student.

(d) By combining air work and landing practice, the landings are not unduly emphasized to the exclusion of his other flying. This tends to keep the student more relaxed and also to make it easier for him to retain his proficiency in the maneuvers which he has had previously.

(5) The slow student started on his landing practice will experience many "close calls" during the trip around the field, particularly in congested traffic. He usually will not realize the gravity of these situations until it is pointed out to him. As a result, he will attempt to play it safe and concentrate on doing this to the extreme, thereby getting himself in all sorts of awkward positions, completely forgetting his relation to the field, his flying, and what he is attempting to do. Not all students will experience all the above difficulties, but most will experience one or more. An explanation of the situation, or keeping the student on the preliminary work until he is definitely ready, will eliminate the majority of the difficulties and make others easier to eliminate.

(6) Although, in glides and stalls, attempts have been made to build up the student's kinesthetic sensitivity, few will have developed it at this time to a degree where it is of primary assistance in landings, although it will be a factor. Vision is therefore the most important sense used. The controls are moved accordingly as the ground seems to rush up at the airplane or come at it more slowly. Unless the student is concentrating on some other factor, such as drift or other aircraft, the reactions on the controls to prevent the airplane flying into the ground will be instinctive and of the self-preservation type.

(7) When the student is erratic in his judgment during landings--that is, leveling off too high one time and flying into the ground the next--such a difficulty may be due to one or more of the following:

(a) Overcorrection, in an attempt to determine the correct position for the focus of vision.

(b) Inconsistency of focus, trying to cover both extremes, near and far, and missing the correct position.

(c) Tension or nervousness.

(8) (a) Most students will be more or less familiar with the meaning of the term "reaction time" since several studies of it have been publicized widely in connection with the driving of automobiles. The change of focus from a long distance to a short one requires a definite time interval and even though it is small, the speed of the airplane is such that it covers an appreciable distance both forward and toward the ground, during this interval. Therefore, the student who alternates his focus from one extreme to the other probably will seriously overcontrol in an attempt to make his reactions take care of a situation which he did not expect. If the focus is changed gradually, being brought progressively closer as speed is reduced, this interval and its attendant reaction will be reduced materially and the whole process smoothed out.

(b) The student's attention should be called to the view of the nose rising into the same position it occupies when the ship is resting on the ground. It will complicate matters and confuse him if, in the early stages of landing instruction, the instructor insists that he look out of both sides alternately. The refocusing time will apply here as in the case of the extremes of distance. However, as soon as the student has made considerable progress, this practice should be required and the habit of looking out of one side only eliminated. Such a habit, if not eliminated, will tend to make the student land with one wing low, which is the one toward which he looks, usually the left, and cause the student to be blind on one side and fail to observe any obstructions or hazards that may loom up.

(c) The student should, of course, have formed the habit of constantly looking on both sides while in flight, and this should be carried on throughout the glide until the lev