US AAF TM 1-210: Elementary Flying - Intermediate Phase

50. Forced landings.--a. General- (1) Forced landing practice not only prepares the student for future emergencies by improving his judgment of speed, distance, and in estimating suitable landing fields, but aids in determining his capacity for additional flying training. Behavior during simulated forced landings is considered a criterion of the student's judgment and technique. Failure during simulated conditions indicates more certain failure during actual conditions. This practice is such an essential part of the student's training that care and consideration must be given to this phase of his work. Other things being equal, technique and judgment in a simulated forced landing depend upon experience. A forced landing that would be difficult for a student with only 10 hours' flying experience should be comparatively easy for one with the experience of 80 hours. For this reason the instructor Must have a conception of' the factors which effect forced landings, their degree of difficulty under various situations, and how much he may reasonably expect from his student.

(2) First explanations made to the student should be confined to the bare essentials. The experience gained through one simulated forced landing enables him better to understand explanations covering his errors and the proper procedure which should govern him on his next attempt. As his experience Increases, so will his ability to absorb details and his understanding of instructions increase.

(3) Each forced landing presents a specific problem and the procedure depends upon the conditions existing at the time. The objective is to land the airplane safely. Due to possible nonavailability of safe landing fields, it may be necessary to land with minimum damage to the airplane and with maximum safety for the pilot. In general, if the airplane can be maneuvered so that it strikes the ground as slowly as possible and on three points as required for a normal landing, the airplane itself may be a total wreck but the pilot is likely to escape serious injury. No definite rules are applicable to forced landings, either as to the use of the parachute or attempting to land when a crash is inevitable. The procedure in such a situation must be decided upon by the pilot whose decision is based upon training and practice. For this reason forced landing practice (simulated) is a very important part of the student's training. By simulating conditions he obtains the experience which he can apply under actual conditions.

(4) Simulated forced landings are given throughout the entire elementary course. They are started as soon as the student has a conception of glides and gliding distance, and instruction will continue until he graduates from the stage. He will average one or more simulated forced landings for each dual flight.

(5) The object of this intensive instruction is to-

(a) So accustom the student to establishing his glide, automatically, select a field and plan his approach during simulated conditions, that when faced with an actual emergency, he will follow this procedure without conscious thought and before he even realizes the gravity of his situation.

(b) Teach him to consider and observe the terrain over which he is flying with the view of determining the best sites for possible emergency landings.

(c) Check the student's judgment, technique, reactions, poise and ability to apply his flying to a practical problem.

b. Wind direction and velocity.--(1) The wind direction and velocity are important during a forced landing since they affect the speed with which the airplane strikes the ground, affect the distance it rolls after landing, and materially affect the ground distance the airplane will glide. Consequently, they must be considered in the original selection of the emergency field.

(2) As a general rule, in forced landings, the airplane should be headed into the wind when the landing is made. However, there are factors which affect the final decision, such as lack of altitude in which to maneuver, slope of the field selected, and the nature of approach obstacles on the ground, all of which may more than offset the advantage of landing into the wind.

(3) The student should determine wind directions from indicators located on the airdromes, smoke columns from factories, houses, brush fires, etc. Prior to flight he has some conception of its velocity from the experience he has had in like situations. During flight, he may determine its relative velocity by observing smoke columns and drift over the ground. For example, if the smoke rises lazily in the air, gradually loses its shape and slowly bends down wind, it indicates a light ground wind and smooth air conditions; if it drops rapidly from its source, hugs the ground, holds its general form and direction, it indicates a strong ground wind. The same information may be obtained from the observation of flags, wind cones, and dust clouds. If the student is observant, he will find many things which will give him an indication of both wind direction and velocity. As his experience increases, he should be able to determine these factors from observation of his drift and relative travel over the ground.

(4) The direction and velocity of the wind are factors in all flying. For this reason, considerable attention is given during elementary flying to forming the habit of continually being aware of the wind direction and velocity. As a means to furthering this end, all training eights and chandelles are performed into the wind, not that the wind is an absolute factor in their performance, but to teach the student to observe and be cognizant of the wind and any drift caused by it. All through his training he is reminded to consider the wind and the manner in which it may affect his flight.

c. Altitude.--(1) From a low altitude (500 feet or less) actual forced landings due to engine failure present difficult problems involving decision and skill. Power available and altitude limit the amount of change in direction that can be made and consequently no definite rules of procedure may be given. Necessity requires that the first rapid inspection for emergency sites be made within a definite area in respect to the position of the airplane and requires a quick, accurate, angular estimation of the distance the airplane can glide. The wind direction and velocity are important and during the first inspection they should be considered, since a field in the general direction of the wind and within safe maneuvering distance would be the best choice. However, too much attention cannot be given to the wind as a factor (due to the limited altitude) and every effort should be made to reach the nearest and biggest clearing which is definitely within gliding range. Once on the ground, a well timed ground loop or the application of brakes may solve the problem of staying within the limits of the clearing. The lack of altitude seldom permits more than one choice of fields and in this respect any change in the initial decision is dangerous.

(2) Even under ideal conditions a forced landing from 500 feet or less may result in a minor mishap. Success in the forced landing depends upon the first reactions of the pilot. If he can accurately estimate the situation, quickly arrive at a decision (it may not be the best) and meanwhile fly the airplane safely--the rest is a matter of maneuvering and the final results will depend upon the terrain. In any event if this first reaction is sound, the airplane should strike the ground under control and in an attitude chosen to give the greatest margin of safety.

(3) During the early part of his elementary training, simulated forced landings from any altitude are difficult for the student as he has not developed the perception which enables him to make a rapid, accurate estimate of the situation. This is because his perception of the factors involved (altitude, terrain, distance the airplane can glide, maneuvering, and the effect of the wind upon maneuvering) is in the process of development. His ability in these respects is directly proportional to his aptitude and the experience which he has gained from practice in power-off accuracy maneuvers.

(4) Sound training principles demand that practice in power-off accuracy maneuvers commence with those from a low altitude, or where the student may readily see objects in their true proportion and relative movement of the airplane is very apparent, and later work up to higher altitudes. In other words, he must first see things as they are. With this experience as a basis, he may then estimate or make allowance for things as they appear.

(5) Due to the foregoing reasons, it cannot be expected that the first few simulated forced landings attempted by the student will be successful, either as to decision or technique.

d. Terrain-The nature of the terrain is determined by its general appearance. Each crop has its individual color and characteristics when viewed from the air. Bright green fields in the midst of brown fields usually indicate early growth grains or irrigated field crops. Since crops are seasonal, the height of the growth and coloring may be estimated by the time of the year. When crops are harvested, all cultivated fields make fair emergency sites. Ploughed fields are usually free from obstructions but recent rains may have made them an undesirable choice although there is the advantage of a short roll. The student should be encouraged to consider the nature of the country over which he is flying.

e. General procedure in forced landings.--Assuming that available altitude is sufficient to allow time for selection of a field and give freedom when maneuvering, the instructor should insist that the student

(1) Relax on all controls, assume normal flight.

(2) Automatically establish glide.

(3) Look for fields in the direction that is easiest for the pilot to observe to each side and forward and within safe gliding distance. If these appear to be poor prospects, observe in the more difficult directions, beneath and to the rear. If there are several available, select the one which appears-

(a) To be large enough.

(b) Located. in direction favorable for landing, considering the pilot's estimate of the wind, his relative position, and altitude.

(c) By its color and general appearance, to possess suitable characteristics.

(4) Select-the center of the field as his first objective or landing point. (A definite portion of the field should be selected and this portion well within the field.) By so doing, it will automatically allow for reasonable errors in underestimating the strength of the wind or the distance the airplane can glide.

(5) Plan to maneuver to a general position just to the leeward and to one side of the field (selected key position) so that landing may be made from a gliding turn and plan to have sufficient altitude when that general position is reached. Remember that the pilot does not place too much consideration on the altitude indicated by the altimeter but is mainly interested in whether he has enough, too much, or too little in which to accomplish his purpose.

(6) As the approach is continued-

(a) He should be able to make a closer estimate of the distance he will glide, as from observation of his rate of approach, he has determined the general direction and "strength" of the wind.

(b) Obtain a more accurate estimate of the nature and height of approach obstacles.

(c) Select the best portion of the field for, the landing point.

f. Salient points-(1) Once a field has been selected, the student should not change his choice but should make every effort to land in it.

(2) First instruction should be a one, two, three order of procedure: first, get the airplane into a safe glide; second, look for a field; third, maneuver in order to reach it. With practice, first and second procedures are simultaneously executed and the problem becomes one of maneuvering. As the student's experience increases from the practice of simulated forced landings and other power-off work, with proper guidance and correction he will be able to increase the area included in his first inspection (to each side and perhaps to the rear of the airplane). This will give him a greater choice of fields, more ease, and time to note the characteristics of the emergency sites and with consequent better judgment in his final selection.

(3) As has been stated before, success in forced landings from a low altitude depends upon the first reactions of the pilot. The speed and manner of this first reaction is a personal quality and there are definite minimum traits which are required. Unless this primary reaction is sound, ability to maneuver is of no practical value as the initial delay, due to the first unsound reaction, causes the loss of too much valuable altitude.

(4) Accuracy in maneuvering should improve as the student obtains more experience as a result of practice in power-off maneuvers such as 180° side approaches and 360°. Consequently more can be expected from him as he progresses through his training.

(5) As in all student training, practical demonstrations by the instructor must be given in order to clarify the situation and present the student with an actual picture of what is desired.

(6) From higher altitudes the forced landing becomes less difficult as a rule for the experienced pilot. The additional altitude affords a greater choice of emergency fields, more time in which to arrive at a decision, and more opportunity for the application of aids learned through experience such as "S"-ing", "playing the turn", simulated use of the flaps and the various accuracy approaches. The instructor's efforts should be directed to the end that the student takes advantage of the opportunities afforded when simulating forced landings from a high altitude and. not waste them by careless, ill-considered decisions and useless maneuvering.

(7) A constant gliding speed, even though it is slightly too fast, is imperative as otherwise it is impossible to obtain reasonably exact information as to the rate of approach.

(8) Violent maneuvering should be avoided as this tends to distract the student's attention from his main objective and make him too conscious of the actual handling of the airplane. Violent maneuvering also prevents him from obtaining a true conception of wind drift or the comparative velocity of the wind as it is then too difficult to disassociate the effect of the rapid maneuvering from any ground movements caused by the wind. It should be kept in mind that several well timed gentle turns will make it unnecessary to turn steeply when close to the ground and thus will afford an opportunity to "S."

(9) The value of "S" turns and gentle turns must be stressed during simulated forced landings.

(10) The poor expedient of increasing the gliding speed, or diving, to cover up an error of "over shooting" should be avoided and an explanation made to the student as to why such a method is impractical. While such a procedure may have some advantages in certain primary types, it is dangerous habit to cultivate as with the more modern types of airplanes it gains nothing and the additional speed must be dissipated before the landing can be made.

(11) The main objective, landing in the field selected, should not be lost sight of. Concentrating too intently upon intermediate objectives, such as the key position, may cause unconscious maneuvering to reach these objectives rather than the field selected. Intermediate points are a means to an end and enable the pilot to estimate drift, relative loss of altitude and relative rate of approach.

(12) Unless his actions are dangerous, the student will have a better understanding of corrections if they are given to him after he has completed his simulated forced landing, rather than during the maneuver.

(13) The instructor will open the throttle upon recovery from a simulated forced landing but it must be forcibly impressed upon the student that he has the controls throughout the recovery unless the instructor indicates otherwise. After the throttle has been opened the student will execute a normal take-off procedure, including the first turn, terrain conditions permitting.

(14) Quick, accurate perception, positive decisions, and ability to handle the airplane are the requisites of all forced landings, real or simulated.

(15) In airplanes equipped. with flaps, their use should be simulated in simulated forced landings, as they might actually be used in real forced landings. The student should give the instructor an easily understood signal when, in his judgment, flaps should be used. They will not actually be used unless a landing is contemplated.

g. Rules.--The following rules should be impressed on students:

(1) It is impossible to dive down to a field and land on it. Speed is essential, but too much can be just as disastrous as not enough.

(2) A normal glide cannot be stretched.

(3) It is impossible to glide low over a field and land on it.

(4) Always remember the main objective--a safe landing.

(5) Be cool and calm--a forced landing is after all only another landing.

(6) Use a normal approach which already has been learned.

(7) Wild gyrations, violent slips, and other extraordinary maneuvers are unnecessary and usually result in failure to accomplish the desired result.

(8) Always have a reasonably safe field within gliding range.

(9) Do not change your mind after making a selection.

(10) There is only one hard and fast rule for forced landings--they must be accomplished safely.

51. Step turns.-- If, in gentle and medium turns, the student has developed the ability to coordinate the movements of hands and feet and is able to maintain constant altitude by means of elevators, steep turns should not be difficult. The maneuver is merely an elaboration of what he has been practicing but requires firmer and more sustained application of pressure upon the controls with a consequent greater change in the attitude of the airplane. Since steep turns are the basis for chandelles and lazy eights, considerable time and practice should be devoted to them.

b. The maneuver should be flown smoothly. During demonstration and first practice by the student, the turn should not be steeper than approximately 60° or not the maximum turn that can be properly flown. As the student develops proficiency, the turn should be steepened to a maximum of approximately 70°. Turns much steeper than the latter mentioned cannot be flown with ease, and the violent efforts necessary will break the continuity of training. Maximum steep turns should not be given until the student has acquired control touch and a realization of the limitations of the airplane.

c. The student should attempt to associate the pressures he is using with the responses of the airplane. He should be conscious of the pressures he is using and the direction of application of such pressures until they are firmly established and have "meaning" to him.

d. in the transition from medium to steep turns, as the bank steepens, pressure must be increased upon the stick in order to compensate for the tendency of the nose to lower and the airplane to slip. This effect is due to the change in direction of effective lift and action of the rudder when going into the turn, both of which tend to cause a loss of altitude. To offset this condition requires that the stick be used smoothly and constantly until the turn is established. Due to the simultaneous aileron-elevator use of the stick, the pattern of its movement must be rounded. Properly timed, the rounded movement automatically corrects for the conditions which tend to prevent maintaining constant altitude. This rounded movement of the stick results in smoother flying in all turns but in shallow turns the rounded movement is slight and usually not considered.

e. The common fault of the student is to push the stick to the side, wait for the bank to become steep and then pull back on the stick, or in other words, execute the maneuver in a series of steps. Such actions cause slipping during the interval while waiting for the bank to steepen and later, when the elevators are used, they must be used excessively to correct for the slip with the result that, after the turn is established, too much pressure is brought to bear upon this control in proportion to the steepness of the turn.

f. The rudder functions in a normal manner. It should be used firmly with the ailerons and efforts relaxed upon it at the approximate time when efforts are relaxed upon the ailerons. After the turn is established, momentary pressure may be necessary upon this control in the direction of turning in order to offset any premature use of the elevators.

g. It is common belief that in steep turns, or during inverted flight, the controls reverse in their functions, that is, the rudder becomes the elevator and the elevator becomes the rudder. At this time it is well to explain that the controls never change their functions. The attitude of the airplane may change in relation to the earth and consequently the attitude of the pilot in his relation to the earth, but in relation to the pilot the controls will always function in the same manner, that is, use of elevators always forces the nose of the airplane toward or from the Pilot depending upon the direction that pressure is exerted; ailerons always force the wings away from the pilot, depending upon the direction that pressure is exerted. Considering the pilot as the axis of movement, the controls always function in the same manner.

h. The steep turn affords the instructor an opportunity to explain effectively the marked tendency toward stalling while in the turn and the danger incident thereto due to the centrifugal force set up in the turn. This, in reality, amounts to increasing the weight until more power is needed to prevent stalling than is available, depending, of course, upon the steepness of the turn. This is one of the reasons why steep gliding turns and turns with minimum power should be avoided by the inexperienced pilot while near the ground.

i. An excellent exercise for perfecting control pressures in steep turns is to require the student to roll from one steep turn to another changing direction 180° or less depending on the proficiency of the student. (Coordination Exercise.)

52. Elementary eight (fig. 4) .--a. An eight is a training maneuver in which the path of the airplane roughly traverses the outline of the figure eight. In all. except lazy eights, the eight is considered as lying in a horizontal plane.

b. The purpose is to-

(1) Improve turning.

(2) Develop ability to divide attention between the actual handling of the controls and outside objectives.

(3) Develop ability to think and plan ahead of the airplane.

(4) Enable the student to learn that radius of turn is a measure which is affected by the degree of the bank and which must be considered in planning the turn to arrive at a definite objective.

(5) Demonstrate the manner in which drift affects the track upon the ground and the methods used to correct for it.

(6) Build the student's confidence in his ability to handle the airplane when close to the ground.

(7) Develop perception of the required altitude.

c. The following factors should be given consideration by the instructor prior to undertaking either of the two types of elementary eights:

(1) Difficulty of the maneuver.--Considering the student's experience could he be expected to perform it after a normal amount of practice? Eights become more difficult in direct proportion to the amount of attention which must be diverted from the actual handling of the controls.

(2) Steepness of the bank to be used.--This should be within the range in which the student has had experience.

(3)     Altitude. --Should be 500 feet, the same as that used for traffic.

d. It is important that the instructor explain the effects and the methods used to offset drift and poorly selected initial banks which are too shallow or too steep to permit arrival at the desired objectives. Those explanations should be made while on the ground and stressed during practical demonstrations in the air. Unless this is done the student, very likely, will not anticipate the airplane's position or plan sufficiently far ahead of his actual position. As a result of this delayed planning, or lack of any planning, last minute corrections will require hurried changes and adjustments. Since the rudder is the most natural corrective control to use, undesirable factors of skidding or slipping will be introduced at a time when all effort should be devoted to coordinated use of aileron and rudder.

e. All eights aid in developing the student's ability to think and plan ahead of the airplane and, obviously, this cannot be started too soon, provided the demands are consistent with his experience. Blackboard sketches clarify verbal descriptions and afford a means of demonstrating the effects of drift and poorly selected turns as well as the methods of correcting them.

f. Description and method of execution are as follows:

(1) Figure 4(1) Select the intersection of two roads, or the intersection of two similar landmarks, as the axis of the maneuver. While in level flight, maneuver the airplane so as to complete the turn at the intersection and pass through it while in level flight. Repeat the process in the opposite direction. The maneuver should be started so that the airplane will be traveling into the wind as it changes from one bank into the other. Perfect execution of this maneuver will result in two perfect circles being formed.

(2) Figure 4(2).--(a) Select the intersection of two roads or the intersection of two similar landmarks, as the axis of the maneuver. The wind direction should be parallel or nearly parallel to one axis. At 500 feet, maneuver the airplane so that it passes through the intersection and bisects the 90° angle formed by the two roads. Continue level flight for a short interval. and start the turn so as to be in the steepest part of the bank when the road is crossed and perpendicular to it (into the wind). Recovery from this turn must be started as soon as the road is crossed, completely recovering in time to permit straight and level flight for an interval before passing through the intersection at 45° again. Repeat this maneuver in the opposite sector. If a strong wind is blowing the interval of straight flight will have to be shortened and the bank started earlier. Wind correction will also require a delay in the recovery from the bank after crossing the road at 90°. The correct execution of this maneuver will result in a perfect figure eight.

(b) Common errors.

1. Failing to determine wind direction in relation to crossroads.

2. Failing to maintain proper altitude.

3. Failing to correct for drift.

4. Not bisecting angle formed by crossroads.

5. Skidding on turns.

6. Failing to make both sectors of figure eight of equal size and shape.

53. Chandelle (fig. 5).--a. General,(1) The chandelle ts essentially a training maneuver, combining several phases of flying which have previously been taught, such as a shallow dive, climbing turn, steep turn, and recovery from steep turn when the speed of the airplane has been materially reduced.

(2) The chandelle requires that the airplane be under control at all times, although, during recovery, speed is reduced to a safe minimum. In this respect it continues the process of developing an awareness of the factors indicating loss of speed and yet

it is more advanced than a partial stall in that the student is required to devote his attention to other matters at the same time. As such, assuming sufficient practice to obtain experience and an understanding of the maneuver, its execution is an indication of the student's progress.

6. Description- The chandelle is an exaggerated climbing turn in which the airplane changes direction through 180°. The maximum climb and the maximum bank occur at approximately the midpoint of the change in direction. Recovery starts at this point, or very slightly later, and is completed when the airplane has changed its direction through the specified amount. Upon complete recovery, the flying speed should be reduced to a safe minimum and the airplane approximately level. Turning rate should increase and decrease uniformly throughout the maneuver. The maneuver should be completed by utilizing initial speed plus the power from the engine. It should be performed smoothly and "flown" throughout.

c. Execution- Advance throttle to slightly more than cruising position and do not retard until the series of maneuvers is completed. Nose down to obtain some excess speed. Roll into a gentle bank and pull the nose into a climb increasing the bank up to the midpoint of the turn. When past the 90° point in the turn, begin to decrease the bank slowly, holding the airplane at the same rate of climb by using as much elevator pressure as possible without increasing the climbing angle. When the turn is approximately three-fourths completed, begin lowering the nose while continuing the roll out. The 180° point can now be seen and the roll-out process slowed down or speeded up so that the wings are exactly level at the point of completion. The nose should be held slightly above the horizon until cruising speed has been regained.

d. Comments-(1) The limits of the chandelle lie between a level turn as a minimum and an Immelmann as a maximum. This would place it as a "step-up" maneuver although it has sufficient value in itself to be well worth the time spent on it.

(2) The initial speed obtained determines the extent of climb permissible during the maneuver. Since no two pilots obtain the same initial speed, the outline of the maneuver will vary accordingly. This is probably the basic cause for the students, complaint that each instructor executes chandelles differently.

(3) The instructor must judge from performance where the student is having his difficulties. If it is in the initial speed or the initial bank, these may easily be corrected by amplifying his description of the maneuver or exaggerating the student's errors. If in errors of coordination, timing, etc., the same errors will probably be found in other work, although perhaps not to such an exaggerated degree. Eliminate difficulties in the understanding of the maneuver and any that remain must be due to technique in the component parts, that is, climb and various degrees of turns. To correct, do not continue on the chandelle but go back to practicing the components. After a reasonable amount of practice has improved proficiency in the components, attempt the maneuver again. If the same difficulties exist it is evident that the trouble lies with the student. To eliminate all possibilities of doubt, try some other maneuver, such as the lazy eight and repeat the process.

(4) The instructor must realize that devoting entire periods to practicing chandelles, or any other maneuver other than power-off accuracy work, especially when the student is having trouble with them, is not conducive to building a high state of morale.

e. Common errors. --(1) Concentrating on the nose to the extent that he fails to obtain a picture of the attitude of the airplane.

(2) Initial bank too steep, when elevators applied, causing the maneuver to be nothing but a steep turn with the nose slightly above the horizon. This same effect is obtained by banking too rapidly and delaying elevator action.

(3) Initial turn too shallow without increase of bank during the climb. This causes speed to be lost in climbing to such a degree that it is impossible to complete the change in direction without stalling. This same effect may be caused by applying elevator too soon and too rapidly.

(4) Starting correctly but allowing bank to increase too rapidly so that the arc of the maneuver is too flat and inconsistent with initial speed.

(5) Failure to maintain correct pressure on rudder while bank is increasing and speed decreasing (allowance for torque).

(6) Failure to maintain continuous backward pressure on the elevators until the maneuver has reached that phase where it is merely recovering from a steep turn.

(7) Allowing the airplane to overbank beyond the vertical.

(8) Too early and too firm application of the rudder at the beginning of recovery. This fault will cause slipping and prematurely stop the turning moment before the complete change in direction has been made.

54. Lazy eight (fig. 6).--a. General.--The lazy eight is essentially a training maneuver. Its performance combines dive, climb, and turn. As with all composite maneuvers, it requires ability to execute its components and blend them together into one smooth, continuous maneuver.

b. Description.--The lazy eight is a turning maneuver during which the nose of the airplane roughly traverses the outline of a figure eight lying on its side in a vertical plane. A fixed, geographical point Is selected for the axis of the maneuver. Part of the arc of the eight is below and part above the horizon. The speed is varied from excess at the bottom to maneuvering flying speed at the highest point of the loops of the eight. The turning rate is approximately uniform throughout.

c. Execution.--Select a fixed, distant, easily distinguishable Object upon the ground as the axis of the maneuver. Turn the airplane so that its flight path is approximately 90° to the point selected. Ease into a gentle dive to obtain some excess speed. Start up in a straight climb and as the nose reaches the horizon, roll into a gentle climbing turn. Time the rate of climb and increase in bank so that the peak of the arc is reached at approximately 45° of turn. From that point the nose starts down and passes through the point. As the airplane is flown through the point, the dive is continued and recovery from turning so timed that when completed, the airplane is in a level position approximately 90° to the selected point, with just sufficient excess speed to repeat the maneuver. Repeat by turning in the direction opposite to that originally used, thus completing the outline of the figure eight. During practice, several eights are performed consecutively.

d. Comments.--As a training maneuver the lazy eight possesses many advantages.

(1) During its performance the attitude of the airplane is changing continuously and thus the maneuver requires a high degree of timing and coordination.

(2) While, for demonstration purposes, the maneuver can be divided into several steps, its proper performance requires blending into one continuous outline. This factor compels the student to plan ahead of his actual position and anticipate the changing attitude of the airplane.

(3) Since the maneuver is made in relation to a fixed point upon the ground, it requires a high degree of orientation, not only as to the attitude of the airplane in relation to the horizon, but also in relation to the fixed point.

(4) The fixed point factor places the maneuver in the same category as elementary and pylon eights, that is, proper performance requires that consideration be given to ground objective, rate of turn, and radius of turn. However, it differs from these last named maneuvers in that the factors of turning must be considered in an oblique plane rather than the horizontal one

(5) Since speed is varying during the maneuver, its performance aids in the development of those sensory factors indicating loss of speed and at the same time does not permit devoting all attention to speed factors alone.

e. General discussion-(1) The limits of the maneuver lie between a steep turn as a minimum and the half roll as a maximum. For training purposes the maneuver is performed approximately midway between the two extremes and the initial speed becomes the deciding factor. If the maneuver is too shallow much of its training value is lost, especially in the factor of improving orientation.

(2) In some respects the maneuver is very similar to the chandelle and the practice of one aids in the performance of the other. Similarly as with the chandelle, practice should not be started until the student has obtained some proficiency in steep turns.

(3) When first starting instruction in the maneuver it is best to omit the fixed point and concentrate on timing, coordination, and blending of controls. If the ground element is desired, use a road or similar line as the axis of maneuver or position at which to start recovery and plan for the succeeding portion of the eight. As proficiency develops, introduce the more exacting requirements of a fixed, distant point.

(4) There is a certain rhythm to the maneuver which, once obtained, insures success. However, the student may start hurrying, fail to anticipate the attitude of the airplane, and soon become confused.

(5) Care should be taken to prevent the maneuver from becoming "set-" However, it is best to start with a more or less orthodox type and after proficiency has developed in this one, change the requirements. Varying the requirements, either the fixed point, or the angular relation to the point when starting the maneuver, will prevent any tendency to become mechanical.

f. Common errors.--(1) Failure to acquire sufficient initial speed. This causes so much trouble that the student either falls out of the maneuver, or intentionally increases the dive on the next loop.

(2) Watching the nose so intently that the student fails to acquire a picture of the attitude of the airplane in relation to the horizon, the point, or, in fact, anything that will help him.

(3) Failing to watch the point and maneuver the airplane accordingly.

(4) Placing the airplane directly over the point so that it is necessary to slip or "dive on a wing" in order to pass through it.

(5) Excessive dive after passing through the point. This is due to failure to take up the slack in the elevators so that an appreciable time elapses before corrective action obtains results--error in anticipation.

(6) Starting recovery (ailerons) too soon, or too late, so that the airplane is not placed in position to repeat the maneuver.

(7) Climbing turn carried to the stalling point so that the airplane cannot be flown but must fall, in order to regain speed. This is due either to neglecting to watch the point, failing to detect loss of speed, or both.

(8) Failure to balance the amount of pressure exerted on ailerons and rudder properly, causing excessive slipping and skidding.

55. Pylon eight (fig. 7).--a. The pylon eight is the most difficult of the various types of eights and requires much time and patience on the part of the instructor. In this maneuver, probably more than in any other, repeated demonstration is necessary. The maneuver is one of the best in the curriculum for the development of the student's judgment of altitude, speed and distance, and his ability to fly the airplane correctly while his attention is diverted to an exterior object.

b. Not the least of the benefits derived from the pylon eight is the development of judgment in the selection of pylons. The student must be encouraged to make a choice of pylons quickly and avoid cruising about. At the same time he should become aware that houses, barn lots, and populated areas are to be avoided. Good pylons such as cross roads, isolated trees, hay stacks, and corners of cultivated fields are numerous. Care should be exercised to see that the pylons are on level ground as correct altitude is vital to the correct execution of this maneuver. Pylons should be selected so that a line between them will be at right angles to the wind and the turns around the pylons should be made into the wind.

c. The pylon eight changes in form as proficiency is developed. The pylons are selected closer together and the bank is changed from medium to steep. Regardless of the bank, the line of site from the eye to the pylon should lie in a plane perpendicular to the longitudinal to the axis of the airplane.

d. While the altitude increases as speed and power increase, 500 to 700 feet is approximately correct for primary type airplanes. One of the student's first faults, when he realizes the extreme importance of correct altitude in this maneuver, is to spend too much time looking at the altimeter. If the line of sight appears to move ahead of the pylon and trace an arc around it, then the altitude is too low. In order to correct this apparent fault, a weak student applies additional inside rudder, producing a skid and at the same time holds the original altitude rather than following the skid to force the airplane to a higher altitude. If the line of sight appears to describe a circle in the reverse direction, the altitude is too great. Confronted with this situation the weak student attempts to force the line of sight on to the pylon by use of outside rudder producing a slip which he probably fails to recognize and at the same time maintains his original altitude. The correct altitude is one in which the line of sight remains directly on the pylon and in which the only variation is caused by the degree of bank changing in the turn due to the wind velocity. The instructor should demonstrate that the pylon can be held when the turn is started too low, by skidding and when started too high by slipping. The fallacy of these corrections should, of course, be explained.

e. A student who, after sufficient dual and solo practice, cannot fly the airplane correctly while devoting his attention to the pylons, or who makes the same mistakes repeatedly and does not further develop his judgment of altitude, speed, and distance cannot become a satisfactory military pilot.

Common faults.

(1) Starting at the wrong altitude.

(2) Gaining or losing altitude.

(3) Starting turn too soon or too late.

(4) Starting turn too close or too far from pylon.

(5) Skidding or slipping.

(6) Coming out of turn too late.

(7) Tenseness on controls.

(8) Failure to allow for drift between pylons.

(9) Incorrect throttle setting--incorrect speed.

(10) Poor selection of pylons with respect to wind.

(11) Executing maneuver down wind.

(12) Selecting pylons in rough terrain.

(13) Selecting pylons in populated areas.

56. Coordination exercises.--a. Purpose.-All. maneuvering in the air is accomplished by a combination of the use of the ailerons, rudder, and elevators. Any maneuver, not too complicated, which makes use of these three controls, blended together, is of value in smoothing out the coordination of the student. An advanced coordination exercise fulfilling the above requirements is described in the following paragraphs.

b. Description.--This maneuver consists of continuous 900 steep turns. The airplane is rolled from a steep turn in one direction to a steep turn in the other and timed so that it turns exactly 900. The altitude should remain constant and the use of the controls should be smooth and positive.

c. Common errors.

(1) Loss or gain in altitude.

(2) Slipping or skidding.

(3) Poor blending of elevators.

(4) Rough use of controls.

(5) Inaccurate pattern.