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Turns and Level Are Complex
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Angle of Attack; ...Controls and What They Do; ... Anticipation; ...Holding Headings; ...Oh, that Right Rudder; ...Propwash; ...Propeller; ...P-Factor;...Torque; ...The Gyroscopic Propeller; ...Level Dynamics; ...Turns Lesson; ...Leveling Off from Climb; ...Level Cruise #1; ...Level Cruise #2; ...Level Cruise #3; ...Unable to Fly Level; ...On Making Turns; ...Why Turns Turn; ...Level Turn Dynamics; ...Bank Recovery to a Heading; ...Level Turns; ...Level Turn Exercises; ...Climbing Left Turns; ...Climbing Right Turns; ...Steep Turns; More Thoughts; ...Second Way; Steep Turns (Basic); Steep Turns (Complex); L/R Steep Turns; VSI in Slow Flight and Steep Turns; PTS Steep Turns; Downwind Turns; Impossible Turn; Clearing Turns; Graveyard Spiral; Flying Turns at the End of a Long Rope; Blind Canyon Turn; The Pirouette Turn; Normal Bank Attitudes; ...Turns (Advice); ...Takeoff Emergency Turn Revisited; ...Conquering the Base to Final Turn; ...A Very Close Analysis of Why It Is as It Is; ...
Angle of Attack (AOA)
Your learning progress is directly related to your understanding of how the controls affect flight. Accidents are the ultimate solution of a lack of understanding. A pilot must understand the function of the rudder and angle of attack related to flight. By definition, the angle of attack is the angle made by the chord line of the wing and the aircraft flight path. At a certain critical angle of attack a wing or a part of it will stall regardless of speed or load factor. Stall warners are used because AOA indicators are difficult to install on small aircraft and even when installed the AOA at stall varies however slightly.
A wing can produce lift by increasing the AOA until reaching the stall AOA. AOA is controlled by used of the elevators. Any increase in speed will increase the lift. In straight a level flight lift is equal to aircraft weight. The fact is, airspeed does not cause a stall, AOA causes a stall regardless of speed or load factor. Load factor can be increased by turns, abrupt control movements and dive recoveries. In these instances the aircraft may stall at a higher speed because of the load factor but the AOA is always the same. Load factor 3.8 corresponds to load factor needed to maintain level flight in a 74.7 degree bank.
There is a relatively wide range of level flight speeds. A pilot can by varying power and AOA, one against the other, transition through all the level flight speeds. A fixed power setting and AOA allows a pilot to trim for a hands-off airspeed. Changes of power only in a hands-off flight situation will cause the aircraft to change the nose, up or down, and, with dampening by hand, the aircraft will climb or descend at very near the original speed.
There is controversy between the aviation guru Wolfgang Langewiesche and the FAA as to what flight controls do. Regardless, to place the aircraft into a given position the same essential movements are required. Elevators do control the angle of attack and in so doing they control airspeed. Elevators do not 'elevate' the aircraft except by converting excess airspeed into altitude. The primary factor used to 'elevate' an aircraft is excess power. The landing process is best stabilized by setting constants. Power is the first and easiest constant to set. With power set the elevator becomes the speed control and trim is the 'lock' that will set a constant speed. Once a locked constant speed is attained, small power reductions can be used to control the glide path descent. Maximum power is used to intercept a higher glide slope.
Controls and What They Do
When engineered, an aircraft will have controls that are designed to give a 'feel' of solidness. This design is there to prevent over control. Almost any aircraft can be torn apart but too abrupt control movement. This is why knowing the Va speed is so important to a pilot. Aircraft controls by design try to warn the pilot of potential dangers by providing feedback. Every control movement gives the pilot a 'feel' for what the aircraft is doing. Designs for differing purposes set the control force required for a given maneuver.
Designers try to harmonize the control forces around the three axes. The standard control force rations are 1:2:4. The roll axis force is 1. The pitch forces are 2 or twice the roll axis required force. Rudder forces are 4 or twice the pitch forces required. The axes are the basic elements. The placement of controls and their required forces are built around the force capabilities of the human body.
Since the movable control surfaces are distant from the pilot, the use of rods, cables, chains, and associated levers, pulleys, hinges and horns are needed to provide the connection and desired movement. An unwanted factor in this connection is friction. Frictional forces have a negative effect on a pilot's ability to trim and stay trimmed. Friction can be the subtlest force faced by a pilot. When trimming and staying trimmed becomes a problem, suspect friction as the culprit.
The 'feel' on the controls is proportional to the airload on the control surface. A control has a neutral or trimmed condition in normal flight. The further from this condition the surface is moved by the pilot, the greater becomes the control force required. This occurs even at slower airspeeds. Control 'feel' is a tactile pilot indicator to be added to wind noise, propeller beat and engine sounds as an airspeed indicator.
Student pilots must be taken through basic maneuvers so as to learn by experiment how control force feels. Once these forces and their changes have been experienced they can easily be transferred from aircraft to aircraft just as we do with automobiles. Once you learn to fly smoothly in one aircraft you can learn quickly to fly in another. Engineered force-feedback is basic to all aircraft design. A pilot does not watch the yoke move; he feels the movement and the pressures.
Feel and movement of the controls can be altered in an aircraft. Spades, servo tabs, counter weights, springs and aerodynamic design are commonly used by engineers to affect changes. Size, strength, and placement are used to reduce some of the forces required by the pilot. From a given trimmed condition every control requires an initial force to make it make its initial move. This beginning force is called 'breakout'. If this required force were not there it would be impossible to fly smoothly while holding a control. With 'breakout' force required a plane's controls will only move when intentionally forced past the 'breakout' pressure. The 'breakout' force is a very carefully selected item of control. It must be there to prevent the unintended pressures and yet allow very small-intended pressures to have effect.
The primary controls are the elevators, ailerons and rudder. These provide primary movement around the axes of flight. In combination, they give coordinated movement around the axes of flight. Engine power is an additional primary control of pitch. Again, in combination, it gives coordinated movement. No change in one axis occurs without having some effect on the other axes.
Secondary controls include trim and flaps. Devices that augment engine power and control operations, weight, center of gravity and load factor have secondary effect on control. Complex aircraft may have additional controls. The effect on all controls is dependent on conditions of altitude, speed, temperature and weather.
Neutral pitch is engineered into the placement of engine, wings. horizontal stabilizer and loading limits. The pitch is moderated to a designed degree by elevator, engine power and trim. Any change in elevator or engine power along with the rapidity of change requires coordinated control movement in the other axes. To change only pitch, by whatever means, some additional combination of rudder and aileron is required.
Ailerons "control" bank angle, roll and roll rate but, in combination with the other controls. On application of aileron in a turn, rudder must be "coordinated" to keep the tail behind the nose; elevator is used to counter loss of vertical lift. Ailerons work in opposite directions, usually in differing distance and with an effect called adverse yaw. The down aileron gives lift and drag (induced). The drag resists the turn so that rudder is applied for coordination.
Rudder is used most often in anticipation of known requirements from the other controls. Rudder will induce roll as well as yaw. The rudder can be used to raise a wing in a stall. Anticipatory rudder is applied to counter the effects of power/pitch applications. A rudder applied yaw is used to make possible crosswind landings. P-factor, torque, precession and slipstream all require use of the rudder. Skillful rudder on the ball and in anticipation is the distinctive mark of a good pilot.
Power is a pitch control. Just adding power (no other control input) will cause the nose to rise and roll to the left. Speed will decrease. In a turn, power will make the left turn possible with little or no rudder but require rudder to "lead" the right turn. There are countless cause/effects in the creation and control of a given airspeed and pitch condition. If you are ever asked about what controls airspeed and pitch, just say, "The pilot".
The ability to anticipate changes in control pressures required for a particular maneuver must be developed. Failure to anticipate rudder movement required to move the nose as airspeed decreases is a most common flight error. The behavior of instruments such as the airspeed indicator and vertical speed indicator that lag in relation to sound and attitude changes must be expected and understood. Chasing the airspeed indicator is a common student fault. Even worse is not recognizing that the VSI (vertical speed indicator) takes about 12 seconds before giving accurate indications unless the control movements are exceptionally smooth. Starting the trim from a known position and keeping track of its movements in various flight configurations makes possible rapid/correct trim pressure corrections.
--Practice of the right kind makes perfect
--Don't begin a maneuver until the aircraft is in stabilized flight.
--Start over if a maneuver starts wrong.
--Don't practice making mistakes.
--Self-evaluation is a part of the process
--Be willing to seek advice.
A pilot (not a student) is expected to hold a heading. The PTS allows a + 10 degree or 20 degree range. It is a mistake to be accepting of this range. Successful flying is most dependent upon acquiring and holding a heading, not a range of headings. Success in holding a heading is dependent upon a pilot's ability to 'hold' the yoke in one position while attention and movement is directed elsewhere. It doesn't come easily or cheaply but it is there to be achieved. Rudder alone will do the best job.
Turning to a heading is another much sought skill. The variables in a turn far exceed those in level flight headings. The turn has the angle of the bank, anticipation of yoke pressures, and airspeed as a factors. The quality of the turn is measured by the pilot's ability to determine when to begin rolling the wings level, when to stop at level and most of all how to keep it there during the transition. For every degree of bank and airspeed we must learn what to do and when to do it.
Other opinions to the contrary, the thirty-degree bank is the safest and most controllable bank. The turn can be cleared and completed in a minimal time. The established bank is quite stable in comparison with others. Making a standard bank procedure develops a sense of turn time and direction that is easily adapted to airport patterns. This stability can be demonstrated by entering a 30-degree bank, putting in about 1/2 turn of trim to hold the nose and then holding the bank with light rudder. It will hold both bank and altitude better than in any other banked condition.
The preferred method of recovering from a bank to a selected heading is to begin recover at half the number of degrees in the bank. A thirty degree bank's recovery will begin at 15 degrees before the desired heading. These markings are easily observed on the heading indicator. With some adjustment in the recovery rate this method will work for all banks. In the real instrument (IFR) world the standard-rate turn (3-degrees per second) recovery can be done quite quickly without regard to any rule.
Oh, that right rudder
A pilot should not assume that yawing tendencies caused by attitude, P-factor, gyro effect and lift are limited to tail draggers. Any correctly flown single engine propeller driven aircraft will respond to these factors and effects. Just how much response is noticeable depends on airspeed and power applications. The left turning tendencies in airplanes is a part of their nature. The pilot must learn to anticipate changes in these effects in use of the right rudder. Reaction will always be too late if not too little. Try holding the nose straight with the rudder momentarily while rolling into a 30-degree bank. to do this you must keep your eyes outside the cockpit and watch the nose. Establish the bank and hold it with the ailerons.
The air flow from a propeller swirls like a corkscrew around the fuselage of the plane. It curls across one wing differently than the other and into the vertical stabilizer and rudder from only one side unless there is one below the fuselage. In a C-150 the left wing will have a higher angle of attack than the right. Higher angles of attack create drag. The prop wash hits the left side of the vertical tail components. Because of prop wash the rudder is the first on your controls to become effective. In low speed high power situations your rudder is the most effective control you have. Both of these effects contribute to the left turning tendency of an aircraft. The pilot must counter these effects by anticipating use of the right rudder.
The propeller has 80% efficiency. This efficiency exists only at the designed cruise speed, which is often faster than the L/D and fuel efficiency speed. A constant speed propeller is most efficient as RPM is at or slightly below manifold pressure. A propeller is most efficient if the leading edge is rounded smoothly and the trailing edge is squared.
The arc that a propeller makes can be considered as a variable pitch disk. In a vertical plane to the horizontal the pitch of the entire disk is the same and it pulls equally side to side and top to bottom. Pitching the nose up causes the blade pitch angle on the left descending blade to increase and the rising blade on the right to decrease. The descending blade takes a larger cut than the rising blade. It is working harder and exerts more pull on the right side. The net effect of this is to turn the aircraft to the left. Some aircraft engine installations point the engine slightly to the right. The right thrust effect is used to offset the p-factor of the descending blade. Usually the pilot must anticipate P-factor with applications of right rudder.
I have always demonstrated torque using a rubber-band powered model while using only the fuselage with no wings or tail. Wind up the propeller and let it go. As the rubber-band unwinds the propeller turns in one direction and the fuselage turns in the other. On the ground the landing gear prevents your airplane's fuselage from turning but it does cause the left tire to exert more ground pressure than the right. This causes a left-turning tendency. Additionally the left wing can be set (twisted) to provide the additional lift that counters the torque effect of the propeller while in the air. This wash-in amount is most effective at cruise. In low-speed-high-power situations the pilot must add right rudder.
The Gyroscopic Propeller
Pitching of the nose causes yaw, and yawing of the nose causes pitching. As mentioned before the propeller is a spinning disk and has all the effects of the toy gyroscope you see in stores. Just by pitching up you can cause the plane to yaw to the left. Yawing the aircraft back and forth with the rudder will cause the nose to vary in pitch.
When a pilot has his aircraft flying so that the amount of propeller thrust is equal to the drag and the wing lift equals the weight plus the negative lift of the tail surfaces he is in level flight. The weight will always be focused to the center of the earth. Up to the wing's critical angle of attack an aircraft and power available will be able to maintain level flight over a wide range of speeds. When the aircraft is flying slowly drag is mostly induced drag. At high speeds drag is mostly parasitic drag.
Enter successive 20, 30 or 45 degree banked turns. Reduce power during the turn. Hold altitude. Stabilize turn at reduced power with trim. Note increased rate of turn at lower airspeed. A one-third reduction in airspeed will reduce your 30-degree bank turn radius by over 50%.
Leveling Off from Climb
An old saying among pilots is, "How long does it take a student pilot to level off?" Thirty-five hours is the answer. It should not take that long if the instructor is on the ball. The student should know for leveling off from a climb at Vy will require a certain amount of anticipation, a certain amount of trim, a certain amount of acceleration, changing amounts of yoke pressure, a power adjustment, changing sounds and some fine tuning. The trick is to put the aircraft into the desired attitude and leave/keep it there.
Demonstrate how pushing forward on the yoke will both lower the nose and level the bottom of the wing's surface with the distant horizon. Have the student perform. Have the student watch the wing and hold it locked level with his arm against the door. Have him note the pressure required. Have him swing his eyes to measure the space between the nose and the horizon. Have him touch the bottom most button on the trim wheel and move it full up while keeping the nose in position. Have him note the gradual change in pressure as the plane accelerates. Power should be reduced when reaching 85 kts. Instructor might make any fine changes needed. If the student needs to search for level flight and is carrying control pressure then he's doing something wrong.
Level Cruise #1
As you reach a desired altitude sight on the horizon under the left wing and move the yoke forward until the wing tip is level. Immediately bring your vision to the nose and hold the yoke so that the nose does not change position relatively to the horizon. Trim to relive pressure but according to the final trim condition desired. If you continue to adjust the trim while the aircraft is still accelerating you will create problems to yourself. Let the aircraft reach its cruise speed (85 kts) and power set before making final trim adjustments.
Level Cruise #2
By going high and then diving to acquire cruise speed you can get to speed faster. Some aircraft actually get on a 'step' like a speed boat and will maintain a higher than normal speed until the condition is disrupted. The reason for not reducing the power initially to 2450 is that some deceleration occurs during leveling off. This causes a 100 decrease in RPM.
Level Cruise #3
The actual reason for having the student to look at the bottom side of the wing for the nose level attitude is because the student does not yet know where to look over the nose. The use of the wing can be substituted by a marker on the windshield once level for the particular person has been determined. Each persons 'level' will be slightly different. Level flight is established and maintained by positioning the nose. Repetition in positioning the nose is the best way for a student to learn where level is. The more often you trim for hands off level the better able you will be able to discern just where level is. With constant power there is one point on the windshield that keeps the plane level, every rate climb or descent has a specific position for placement of that point based on constant airspeed. Airspeed is a relatively coarse way of nose adjustment. It takes & makes a proficient pilot who uses the nose position for level flight. The pilot who trims for his climb and descent airspeeds soon develops a set of constants for the aircraft. With repetitive practice the pilot will learn to feel, hear, and SEE just where a particular configuration and attitude will position the nose.
Unable to fly level
After you have been flying a while either with the instructor or solo a common phenomenon seems to occur where the new pilot is suddenly having difficulty in leveling off. This is normal. As we have trained and practiced we have developed along with the procedures for leveling a set of references. We may have started with the wing on the horizon and gradually been able to reference the nose to the horizon. Now, it doesn't seem to work. We may oscillate in altitude, airspeed and trim for several minutes and still not get it right. It is going to happen.
The reason it this occurs may be due to one factor or a combination of factors. If the weather changes so that your usually clear horizon is blocked by haze or cloud formations you have lost an essential reference. Flying in mountains where the horizon cuts through the mountains can be a causal factor. Perhaps due to a distraction you forget to trim. Power control can cause the aircraft to fail to accelerate or to exceed cruise speed. Any one of these or a combination can cause leveling off problems. You might practice making deliberate errors in your leveling off procedure to ascertain the corrective procedure that works for you.
Most of the small movements evade detection of the eye but are sensed subconsciously by the peripheral vision, dangerously so. In certain pattern turn conditions the peripheral vision can deceive your brain as to the true attitude of the nose.
On Making Turns
In the very beginning of flight instruction and any proficiency check I review the four basics. Of these, the making of turns require the most attention. A properly performed turn is a thing of beauty with just the right amount of aileron, rudder and pitch. Just the other day, I had a student reviewing for her second solo in the pattern. She had what I call an 'a-ha' experience. She had performed the cross wind turn from entry to rollout at exactly 65 knots in the C-150. Such a turn is not easy. The use of rudder must be anticipated along with feather-light pitch pressures.
The aileron into the roll in and out must be smooth and blended with the use of rudder. I want my students to use 30-degree banks, no more, no less. Such a bank is unique in that when reached and held there the yoke will be parallel to the cockpit panel just as in level flight. the 30-degree bank is very stable and can be held there with light rudder pressures. There is only .15 G difference between level and the bank G-forces. The 30-degree bank feels good when done right and held there.
There are distinct differences between left and right 30-degree banked turns. In a Vy climb a turn to the left may well not require any additional rudder pressure except when rolling out. The entry into a right bank from a Vy climb will require leading with the rudder, holding it into the turn and relaxing it during the roll-out. These uses of the rudder are not intuitive and exist to a slight degree even in level and descending flight.
Practice doing the Dutch roll will sensitize the student to the sensations of a slip, skid, and coordinated flight by creating the discomfort of uncoordinated flight. The rigging of the aircraft is a variable factor that accounts for the need of pilots to adjust to each aircraft. The making of 30-degree banks is useful as a maximum limit in the pattern because it makes the turn quickly into the cleared area. A more shallow bank is useful if a higher rate of climb is required as in making a 270 departure. ATC prefers the 30-degree bank to the 20-degree bank because it is less likely to be confused with a wing wobble. 30-degree banks can be checked with both the attitude indicator and the Cessna wing strut being parallel to the ground or horizon.
In making turns there are two criteria that are used around the pitch axis. In level flight it is the altitude and in climbs and descents it is airspeed or rate of descent. The indicator in both cases is the nose and sound. 30-degree banks do not require much pressure but the application an removal of that pressure must be done in anticipation of what is going to be happening.
On rolling into the turn you apply pressure with the forefinger and hold it until beginning to roll out. At this point you apply thumb pressure because the increased lift in level flight always causes a pitch-up unless anticipating counter pressure is applied. The usual rule for rolling -out on a heading is to begin at half-the-angle-of-bank. Students should be encouraged to watch the nose during turns with only quick glances at the heading indicator for the lead-in heading used for rollout. The final heading should be initially acquired by watching the nose. Any fixation on the heading indicator prior to or after roll-out will generate wing wobble. Precise turns are a matter of consistency in the roll-in and the rollout.
Why Turns Turn
A turn is a combination of several aerodynamic factors. Individually each factor has both positive effect and negative effect. Beginning with the ailerons the inside aileron goes up and decreases lift that lowers the wing while the outside aileron goes down and increases the lift that raises the outside wing. We now have roll. Along with raising the wing the outside aileron just by increasing the lift also creates drag. Parasitic drag that is. This drag is a negative that tends to swing the nose away from the turn. This is yaw... Adverse yaw, that is. The combination of roll and drag is called coupling. With roll you get yaw. The speed or rate of your roll entry, by affecting the relative winds of the two wings, causes additional but slight adverse yaw.
Without coordinating rudder to counter any adverse yaw the aircraft is in a slip. The lower wing is faster and moving forward and rising with the increased lift. The relative wind weakly moves the vertical stabilizer away from the turn effectively moving the nose into the turn and reducing the slip.
Coordinated rudder solves all the dynamic equations of the turn. It eliminates adverse yaw and all the forces that reduce roll effectiveness. the rudder must be applied or even anticipated at the beginning of the roll and then pressure reduced once the aileron deflection is reduced. The roll-out to heading reverses the roll-in process. Turns are more enjoyable when the proper rudder forces are applied.
Level Turn Dynamics
A banked aircraft transfers some of the available wing lift away from the vertical into a turning force. It is this transfer of lift that makes it necessary for the pilot to increase the wing's angle of attack to obtain the lift required for maintaining a constant altitude. In this bank there is an apparent increase in weight caused by the horizontal centrifugal forces of the banked turn. At a 60-degree level altitude bank the weight of everything is doubled. (2 G's) A 30-degree bank has an effective weight increase of .15 Gs.
Since the most likely C-150 mid-air will come from a faster aircraft from the rear quarter, always look beyond 90 degrees when clearing but any aircraft above the horizon will pass overhead. Any following aircraft should pass to the right, initiate clearing turns to the left. There is nothing wrong with raising the wing for clearing. The instinctive desire to see around the wing in the direction of the turn is both dangerous and inefficient. You can't really see and you decrease your ability to hold both bank and airspeed. Keep your eyes on the nose and horizon during a turn. Don't turn into an area you have not cleared. Do not pull back on the yoke to recover from a turn or bank, use the ailerons.
Bank Recovery to a Heading
Lead your recovery from a left bank by applying right rudder. Lead your heading recovery by 10 degrees in a 20 degree bank, 15 degrees in a 30 degree bank and 22 degrees in a 45 degree bank. Every recovery from a bank also requires that some forward pressure be applied to prevent the 'pop-up' airspeed loss that will occur as the wings acquire added vertical lift when leveled.
The turn is the only of the four basic maneuvers that exists in conjunction with the other three. The level turn is a balanced condition, as with level flight, where the lift equals the aircraft weight. With constant power the airspeed and angle of attack are controlled with the elevator. Some airspeed is lost during the turn due to an increase in pitch. The rudder keeps the tail behind the nose. The quality of the turn is a blend of yaw, roll, pitch and power. The blend is changed as the angle of the turn increase or if it occurs as level, climb or descent. A climbing or descending bank requires a different blending of these factors.
Elevator controls pitch. Elevator trim is for removing control pressures when a prolonged flight condition or attitude is to be maintained. Entering a 30 degree bank requires slightly forward yoke input on the elevator with the thumb. This prevents excessive loss of airspeed. On reaching 30 degrees a slight back pressure with the finger will give the pitch needed to maintain altitude. Recovery from the bank requires slight forward pressure with the thumb again. These finger applications are more pressures than movement. If the turn is to the right, rudder pressure precedes aileron movement. Recovery from a left turn requires that right rudder pressure precede aileron movement.
The only control difference between the left and right bank is the anticipation and lead required on the right rudder. You lead the right turn with right rudder perceptibly before you need to with the left rudder in a left turn. Again this is because of aerodynamic factors . Likewise, the recovery from the left bank requires anticipation and leading with the right rudder before leveling off. In this instance forward pressure is required to prevent the 'pop-up' from causing an altitude gain when leveling off. The steeper the bank the greater the need for knowing about the amount of anticipation and firm forward pressure required.
The design of most light aircraft gives a stable 30 degree bank hands off with just a little nose up trim. The aircraft will tend to level off from any bank less than 30 and become steeper from any bank more than 30. At 30 degrees the G-force is +1.15, at 20 degrees the G-force is 1.06, at 45 degrees you get +1.41 G, at 60 degrees the G force is +2.0. Aileron must be held into the bank at less than 30 degrees, against the bank at more than 30 degrees and neutral at 30 degrees. Any time the ailerons are not neutral there is induced yaw which must be countered by rudder. Adverse yaw ceases when ailerons are neutral.
A similar maneuver will work with most any G.A. plane but the amount of trim will vary. A bank of less that 30 will cause the aerodynamics of the plane cause it to want to level off. Yoke must be held into the bank. A bank of more than 30 will cause the plane to want to continue on over. The yoke must be held against the bank to keep the bank from increasing.
Level Turn Exercises (Instructor)
Select a flight course on a cardinal heading and toward a prominent point on the horizon. Execute a series of left and right 30 degree banked turns of 90 degrees. The first turn should be to the left. (Any passing traffic to your rear should be passing to your right.) No turn should be initiated without visual clearing. This clearing should include at least 30 degrees to your rear. I recommend saying, "Clear left, turn left." Once the turn has been cleared and the 90 degree reference point selected under the wing the pilot's eyes should be over the nose of the aircraft. Since we are turning left P-factor will aid in coordinating the ball position so little left rudder will be required. Once the 30 degree of bank has been attained the yoke must be neutralized as to bank. (The aircraft in a 30 degree bank is relatively stable.
An aircraft in less than a 30 degree bank wants to level out and must be held into the bank by yoke pressure. An aircraft in more than a 30 degree bank wants to increase the bank and you pressure must be held against the bank. This is part of the VFR to IFR transition problem.) The C-150 wing strut parallel to the ground makes a 30 degree angle bank. Yoke pressure will be slightly forward initiating the bank; slightly back as the 30 degree bank is reached and slightly forward to prevent 'pop up' as the aircraft is leveled off. (The automotive practice of leaning forward, then tilting and turning the head during a turn will cause problems in holding altitude.) As the turn progresses toward the 90 degree point the 90 degree reference will come into view. The leveling off from a left turn requires some anticipation of the pilot in leading the yoke pressure out of the bank with light right rudder pressure. Forward yoke pressure is applied just as wings level occurs.
The turn to the right requires some slightly different techniques. Clearing and selecting the 90 degree point is followed by, "Clear right, turn right." Initial yoke movement into the bank is preceded by right rudder since there is no P-factor assistance. Very little left rudder is required leveling off from a right turn. All yoke pressures and movement are essentially the same. (If a student increases the bank instead of leveling off it is probably because they are using and misinterpreting the attitude indicator instead of watching the horizon.)
The first turns should use visual references then use the heading indicator. (I often reset the heading indicator to get the visual points to correspond to cardinal headings.) Leveling off on a given heading requires only that the leveling pressures preceded the selected heading by a number of degrees half the angle of bank. A 30 degree bank should begin leveling 15 degrees before the selected heading.
The accuracy of the visual reference turns can be demonstrated by having the student note the present heading and a 90 degree visual reference point. Make the turn while the heading indicator is covered; checking only when level. It is important to practice these turns only a few times during each flight. Don't beat on a particular skill for too long. Level turns have skills related to both climbing and descending turns. It is important that the instructor utilize the instructional time and flight segments in the most efficient manner. A good way to provide a break between skill practice is to survey the area for check and reference points.
One of the very first exercises I do with a new student is to justify my insistence on 30 degree banks in all VFR maneuvers. In the C-150, after clearing, I have the student enter and hold a 30 degree bank and give about a half turn of nose up trim, then he is to let go of the yoke and fly only with rudder.
Climbing Left Turns
All turns that are going to exceed the angular range of windshield vision should be preceded by "clear R/L, Turn R/L" Failure to clear will fail any flight test.
Since there is increased P-factor present in a climbing left turn, some right rudder might be required throughout the turn to keep the ball centered.. Even more right rudder will be required when leveling off. The aircraft will tend to lose some indicated airspeed when all turns are initiated. A slight, almost imperceptible forward pressure with the thumb will prevent this indicated speed loss. As soon as the 30 degree bank is reached the thumb pressure is removed and replaced by sufficient one finger pressure to maintain both bank and airspeed.
In addition to P-factor that exists in a climb, in a climbing turn we introduce yaw. Yaw in a turn is caused by drag. Drag, in turn, is produced by a higher angle of attack. The high wing in a turn has more yaw and more induced drag and a higher angle of attack because of the down aileron. The fact that it is moving faster is a minor but existing parasitic drag factor. It is the initial induced drag of the aileron's greater deflection when rolling in and out of banks that increases the need for more rudder
Climbing Right Turns
Right rudder pressure is being held in the climb due to P-factor. Even more is now required to initiate the right turn. Anticipate the need to lead with right rudder in making right turns. Yoke pressures and anticipation is much the same as with left turns. Recovery from the bank requires only that the right rudder pressure be relaxed and then reset for P-factor to climb on heading.
At some point during the first four flights steep turns should be demonstrated by the instructor. You should use a prominent visual reference on the nose at a cardinal altitude. While the PTS (Practical Test Standards) requires only one 360 degree turn, the most instructive steep turn consists of two full 360 degree turns, 45 degrees of bank, a constant altitude, and cruise power. The bank entry to the 45 degree steep turn should be smooth and rapid. Initially check the angle of bank on the horizon against the attitude indicator. Once the angle has been achieved concentrate on the horizon and its angle. Variations of five degrees of bank may be used to control altitude. The new PTS requires only one 360 degree turn with recovery near heading.
After clearing, enter the steep turn smoothly and rapidly, lead with right rudder if to the right. Sight on the horizon and anticipate the loss of lift with a locked elbow on the door and sufficient back pressure to prevent a loss of altitude. Angle of bank may be varied from 45 + 5 degrees to adjust altitude. Using the elevator to adjust altitude gives only an illusion of change. Actually the turn is being made steeper with a resulting loss of altitude, increase in G-forces, airspeed and angle of attack.
Steep turns are precision maneuvers flown as a confidence builder. The vertical lift lost by the steep bank must be replaced by increasing the angle of attack by applying back pressure. The seemingly great pressure required is because of the increase in G force due to the bank. The critical angle of attack of the wing remains the same but due to the increase in weight (G-force) the stall occurs at a much higher speed. (A stall in this situation is called an accelerated stall because of the higher speed.) Rudder is used to compensate for drag /adverse yaw from the raised wing. Once in the turn, the raised wing will travel faster and provide more lift. To compensate for this lift caused over banking tendency the ailerons must be held against the bank.
The steep turn, properly performed as to bank and altitude, will, as the second 360 degrees of turn are performed, come in contact with the wake turbulence of the previous 360 degree turn. This second 360 is no longer required by the PTS (Practical Test Standards) but it is the best way to self check performance of the maneuver. Encountering the wake will cause the wings to rock and maintaining altitude typically becomes a problem. The initial surprise seems to be the cause. The student will instinctively relax pressure when it should be held or increased. If more than 100 feet is lost the process should be started over from the beginning. Since the bank is 45 degrees the leveling off should begin about 22 degrees early. A very positive forward pressure must be applied to prevent a pop-up increase in altitude. The turns should be performed both left and right but perhaps at different time since they may cause student distress.
There are two distinct ways the steep turn may be performed, with or without trim. The unexpectedly high yoke pressures required to hold both the bank and the altitude is difficult for students but very instructive. They should learn to press their arm against the door to lock the pressure and position. The second way is easier but requires some timing. Airline instructors do not allow the use of trim. At the moment the 45 degree bank is attained, give the trim wheel two quick full turns down. This will release almost all of the pressure required to hold altitude. Now most of attention can be devoted to bank angle and the slight changes needed for altitude. The yoke release often caused by the surprise of wake turbulence will be compensated for by the trim setting. However, when leveling off the trim must be removed very quickly before it aggravates the typical pop-up pressures of leveling off.
First: go as quickly into the bank to 45 as you can in both methods. Easy way: Using the tip of your right forefinger quickly make two top to bottom of the trim wheel. Now a light touch will keep you in the bank and at the same altitude. Lead your recovery by 22 degrees and again quickly remove the two turns of trim with your finger tip. Do not pinch the trim wheel.
After clearing turns, choose a reference point or direction over the nose before beginning. You will start your rollout when that reference point first enters the side of the windshield. This gives you a way to keep your head outside the cockpit during the maneuver.
Steep turns can be done using trim or without trim. Learning without the trim is more difficult because of the required control pressures. The steep turn of the PTS requires that airspeed be kept within ten-knots. At cruise power this should not be a problem if some extra power is added once into the turn. when there is no visual horizon it may be necessary to use the attitude indicator. You should practice using both the visual horizon and the AI. At constant power the horizons (actual and AI)in position, you will be holding altitude. You do want to practice your recoveries so as to come out on a predetermined heading.
Flying from the low seat in a turn will commonly cause a pilot to climb. Flying from the high seat will commonly cause a pilot to descend. Tandem seat cockpits do not have this problem. You will have a point on the windshield at eye level that is offset from the aircraft centerline by the same distance as your head. By marking this spot in some way you can make your left and right turns by keeping the mark on the horizon. Some adjustment of the mark is to be expected for different flights and aircraft weights. Your mark will always work for you.
A steep turn in VFR can be referenced to this windshield mark. Just keep the mark on the horizon. Use the center dot on the attitude indicator for IFR turns. The VSI is an early indicator of attitude change. Watch it. Sound changes are early warning signals to check the VSI. Most turn corrections tend to be in excess of what is really required. One technique to use when you make an attitude correction is to immediately take half of it off. This is one way to reduce the tendency to over react.
If you are flying a plane where you can push the throttle all the way in, I suggest that you find out how fast the plane will maintain a steep turn at full throttle. Then, find the power setting that will give you that speed in level flight and use that for your entry speed and power setting. Roll into the turn aggressively and put the power in as you go through 30 degrees of bank.
Go as quickly into the bank as you can. Lock your arm and elbow against the cabin door. Listen to the sounds! As one of the others advised anticipation is the name of the game. Watch the VSI with quick glances. Watch the nose vs. the horizon the same way. You will probably overreact to VSI movement so when you do react release half of the reaction and you will be about right.
The new PTS now requires only a 360 but I suggest that you do a 720. On the second time around you will be in contact with your own wake turbulence if you have done the first 360 well. The wake turbulence is a way to check your performance. Don't do to many steep turns at one time.
Trimming makes the steep turn easier but it bypasses the instructional purpose of doing the steep turn. The purpose of the steep turn is to develop the awareness and anticipation of the control forces and attitudes required. Heavy control forces are designed into the performance of the aircraft when and where destructive G-loads exist. If trim is allowed in steep turns to show the required attitude, then just as many turns should be made without trim to show the required control pressures to attain and maintain that attitude.
A common error related to steep turns is what the pilot does when a loss of altitude occurs. The initial perception is that the loss is due to insufficient back pressure on the yoke. This may well be the case but the recovery of this lost altitude by only increasing the back pressure is not the solution. The increase in back pressure alone will tighten the turn by increasing the angle of bank which will lead to a further loss of altitude. The geometry of the hand, arm and yoke cause this. Any increase in back pressure must be accompanied by a decrease in bank angle at the same time. Often loss of altitude can be corrected by just removing some of the bank. It is this incorrect recovery from a banked turn that leads the graveyard spiral and spatial disorientation. Get the wings level, recover altitude and start the steep turn again. The essential is that the angle of bank be held so that no changes in back pressure are required.
Trimming during steep turns can be dangerous. The potential is there if situational awareness is dimmed. Any descent can become a high speed spiral at excessive G-load. The steep bank should never be entered at speeds over Va. Higher speeds than Va will over stress the aircraft. A steep turn can only be recovered by leveling the wings. Ailerons will still be effective. Rolling out of the trimmed bank without removing the trim can cause a low-speed unusual attitude. Pulling back on the yoke to hold altitude or prevent a spiral dive is more likely to increase the bank and make the spiral more steep. Avoid such trimming at night, IFR, or in low visual conditions.
I recently took a flight check ride where the airspeed was decreased to 80 knots with power at 2200 rpm. I was then told that I was to enter into a steep turn of 45-degrees while adding power into the turn to maintain the 80 knots throughout the turn. I have always considered relatively low speed steep turns as something to be avoided. I did not do well. I had never tried to perform in that manner. I believe it can be done with some difficulty by anticipating the power application. I normally do steep turns at cruise power. More about this later.
Opinion (Another way)
He (instructor) went on to suggest I use a touch of power as you roll into the turn and reduce power as you roll out. Neither right or left turns made much difference but it did make the turn more level and reduced control pressure.
Opinion How to turn in a tight canyon.
Maximum power, maximum pull on the elevator (stall warning going on C172), bank probably greater than 60 deg then watch for reference points on the sides of the terrain. That was the first time I'd done maximum performance turns. It's amazing how small a turning circle you really need.
Steep Turns (Basic)
Pressures keep changing in the steep turn your coordinated aileron and rudder, back pressure, all changing to opposite aileron and reduced backpressure when established at a constant airspeed. If you have gone smoothly to slightly over 30 degrees and held some back-pressure the normal over-banking tendency of the aircraft will wind up at the desired 46-degree angle. It will take opposite aileron to keep it there.
The plus/minus ten-knot speed allowance can be set up either entering the turn or after the turn is established. Enter the turn and add some power in anticipation of a loss of speed. Another way is to wait until the turn is established and then add a predetermined amount of power to stay within the allowance.
The vertical speed indicator is the rabbit to be watched. The slightest movement up or down is a warning of altitude changes soon to follow. The VSI is a more important instrument than the altimeter is during a steep turn.
The recovery from the steep turn is based upon the half-angle recovery method but must be followed by abrupt forward yoke to prevent a sudden increase in altitude. Watch the VSI and lock your elbow.
Steep turns (Complex)
A method is to use additional power to maintain altitude.
Determine in flight the descent rate at a given bank angle when not maintaining altitude.
Add 1" of MP for every 100fpm of sink to maintain altitude.
Technique works only from something less than cruise speed. A good entry speed would be a holding speed or approach speed. Add the throttle smoothly when rolling in the bank and reduce throttle when rolling out.
L/R Steep Turns (Opinion)
One possible factor in making left turns more difficult than those to the right is the asymmetry of the sight picture when making left vs. right turns.
In both cases, the horizon should appear in the same place relative to a point straight ahead of you. But since that point is well left of center, much more of the windshield is filled with the ground during a right turn than during a left turn. This may make your pitch seem much lower during the right turn. You're then applying much more back-pressure than would usually be needed for that seemingly-lower pitch, which perhaps makes the back-pressure seem more than it really is in that situation.
VSI in Slow Flight and Steep Turns
Slow flight and steep turns are areas where a pilot would do well to pay more attention to the VSI. The VSI is a very good precursor of altitude loss. By watching the VSI a pilot will be able to anticipate the need for power sufficient to prevent any descent. In slow flight every change in power should be accompanied by proportionate rudder pressure. In the steep turn you can use the VSI to get the yoke pressure back or forward to prevent altitude excursions.
One instructor suggests using a small isosceles triangle on the windshield as an instructional aid. 45degree; 45degree; left turn right turn edge.
PTS Steep Turns
--Ability of pilot to explain the maneuver.
--Purpose is to show smoothness, coordination, orientation, division of attention and control
--Answer questions related to aircraft limitations and that your aircraft meets or exceeds requirements.
--Not a ground reference maneuver, rather a performance maneuver.
--Knowing that stall speed increases with load factor and need to avoid stall.
--Must be completed no lower than 1500'.
--Make clearing turns before beginning maneuver
--Pilot awareness of traffic, altitude and direction during the maneuver.
--Entry and performance speed not to exceed Va.
--Examiner can specify entry speed.
--Smoothness is an important criterion of excellence.
--PTS only 360 in either or both directions.
--FAA-H-8083-3 Airplane Flying Handbook specifies otherwise. Mostly up to examiner.
--Recover from turn +10 degrees.
--Examiners can use outside reference as target for reference.
--Due to tumbling use of heading indicators may be inaccurate.
--Divided attention inside and outside.
--Be prepared to answer questions related to what you should have seen outside during the turn.
--+ 100 feet of altitude and 10 knots of airspeed.
--Before the maneuver discuss whether or not the use of trim is allowed by this examiner.
--Be prepared to do the steep turn with or without trim.
--Be careful not to increase speed during last part of turn. Common fault.
The downwind turn problem is not one of physics so much as psychological. The sensory reaction to ground proximity, ground speed and flight position is likely to create a situation conducive to instinctive reaction rather than considered anticipation.
Popular wisdom is that a pilot should never turn back to a runway on takeoff. An even older wise axiom is, Never say Never". Studies of the most likely to succeed turn back to the runway is the one that is into the wind at 45-degrees. The requisites are that the turn be coordinated, smooth and on airspeed.
This maneuver must be practiced at altitude until performance meets the highest standards of angle, airspeed and smoothness. Lack of coordination will cause a stall and spin entry. Only practice of the right kind will prepare a pilot for low level performance.
The Vy climb speed used for takeoff is very nearly the same as the standard approach speed and the 45-degree steep turn stall speed. The stall margin requires strict attention to the performance of the turn and foregoing ground proximity awareness. Success means survival. You will not be able to get back to where you lifted off. You may be able to reach the departure end of the original runway. This is better considering you will have a tailwind. Anything over a ten-knot tail wind would negate making the 'impossible turn' possible. Crosswinds, crosswind runways, and local factors can change your options.
--The most basic 'clearing turn' is with the neck prior to starting the engine and YELLING clear.
--The next 'clearing turn' occurs when you make a 360 prior to taking the runway or at least facing the final approach course so as to clear both base legs.
--The training 'clearing turn' during climb out that I use is practicing Dutch rolls. This clears the airspace covered by the raised nose.
--The 'clearing turn' I use prior to airwork can either be a left 360 or a left 90 followed by a right 90. The initial turn is always to the left since passing traffic should pass on the right.
--Found a CFI did not know what a course reversal was.I usually initiate course reversals with a left 90 and then a right 270 for the same reason stated above. The best time to look for traffic in a Cessna is when the wing is raised away from the turn. The course reversal is another good way to make the 'clearing turn'.
-- I have found that the safest 'clear area' is to avoid flying at thousands and five-hundreds when within 3000' AGL. My local safe area is to fly below Class B shelves at 2700 AGL.
Graveyard Spiral (Hood)
This is a slow turn that will gradually increase in bank angle because of the lift differential between the inboard and outboard wing. The pilot does not need to apply any input. Bank angle increases result in the nose dropping and speed increasing. An aircraft can be expected to have the wing fail upward and forward under the positive-G overstress of this situation. However, if the speed is greater than 15% of the Vne the failure may be downward and aft. Flutter causes this type of failure.
Flying Turns on a Point Around a Long Rope
This method not only works, it has been around for a while. It was developed by Nate Saint, missionary pilot to South America in the 1950's. He and his buddy Jim Elliot used to lower gifts to the natives this way. They also used a telephone in the bucket for ground to air communications. I read a biography on Nate that included some of his original drawings of how it works. He has some other aviation inventions, too, like a redundant fuel delivery system that works on gravity and was made from non-aviation spare parts...
Blind Canyon Turn
The infamous "blind canyon 180" can get you into a mess of trouble if you don't have a complete understanding of minimum radius turn theory. Just hauling back with full power isn't the whole story here by a long shot. You might not have the room to make it using a level turn. First of all, the stall speed increases by the square root of the load factor x the wings level stall speed as bank is increased, so if you have a stall speed of 60kts wings level, you will pay off at 85kts in a 60 degree bank. And this is just the beginning of the story. There is also a specific airspeed where minimum radius, best rate, and maximum available g can be married to produce an optimum turn. In fighters, we call this corner velocity or corner speed.
For a typical general aviation light airplane, this speed can be found at the intersection of the aerodynamic limit and limit load factor lines on a v/g diagram. It loosely translates to your Va or maneuver speed. Remember, this all applies to level turns. It's possible to reduce the turning radius even more than this by using the vertical plane in the turn. Again in fighters, we call this a high yo yo. You can consider it a wingover. By raising the nose and bleeding off airspeed, then allowing the nose to come through the turn with maximum bank unloaded, you can severely reduce the horizontal turn radius for the turn. There is a level of performance even above these maneuvers that is possible with aerobatic training, even if performed in a normal category airplane. If performed properly by a trained pilot, a hammerhead turn will produce an absolute minimum radius 180 by using the vertical plane almost entirely to reduce the horizontal turning component to near zero. This would be considered an emergency procedure in a normal category aircraft, although it can easily be done within the allowable load factor limits.
The bottom line on blind canyon turns is this. Don't get caught in this situation in the first place, but if you fly in terrain where an emergency maximum performance turn could save your life, go out and get some competent instruction in these procedures. .Just yanking it around with power isn't the way to go!
Fly safely, Dudley A. Henriques
The Pirouette Turn
Pre-decisions are credited by accident survivors as having much to do with their success. The pirouette,
pivot turn, is an emergency escape procedure as a last option when you have run out of aircraft performance and turning room. The entry into this situation requires a continuous series of bad decisions. Even then the pirouette will not be of help unless you have practiced to proficiency. An incorrectly performed turn will only make a bad situation worse. This means you must practice it. More importantly, the pilot who understands the factors leading to will never need to make the turn.
The pirouette turn allows a 180-degree turn with a minimum radius and no loss of altitude. This is a maximum performance turn required when you have run out of performance. The procedure is to reduce to idle power, put in full flaps and maintain wings level. Then before you begin to sink you put in full power, pitch up the nose and kick in full left rudder. Milk off the flaps.
The aircraft will have made 180-degrees of turn faster than you can say what to do. It is most effective to the left. But could be done to the right if you did not add power. The bank angle should be shallow enough to avoid a stall but steep enough to minimize the turn radius. It is my opinion that this maneuver could be practiced at altitude but perfected at real or simulated high-density altitudes.
1. Zero bank for level flight
2. Shallow bank that requires yoke pressure into the bank to remain constant and prevent leveling.
3. Medium bank that can be flown without any yoke pressure but requires trim to hold altitude
4. Steep bank that requires yoke pressure against the bank to prevent increasing angle.
Is your difficulty with coordination, maintaining altitude, or something else? Since you fly gliders too, I'm doubting it's coordination. But just in case, remember that you only have to counter-act adverse yaw when you are rolling, not turning! As you roll into the right turn, the aileron on the left wing moves down creating more lift and more drag. So applying right rudder yaws the nose to the right. I know you know this, and I apologize for repeating it. But what many students don't realize is that once the bank angle is established and the ailerons on neutralized, the adverse yaw also neutralizes and you no longer need any rudder pressure! Take your feet off of the pedals (so to speak). When you want to roll out of the right turn, the aileron on the right wing moves down causing more lift and more drag, which requires left rudder! Very few students remember this.
Once the wings are level, take your feet off of the pedals. Next time you're flying, practice rolling into and out of turns. Be aggressive enough with the controls so that you can feel any skidding and slipping. Don't stare at the ball or the string; try to feel it. If you feel pressure on your right butt cheek, you need more right rudder, or more left yoke/stick. If you feel pressure on your left butt cheek, you need more left rudder or right yoke/stick. An easy way to visualize this is to think of your car. A car only yaws. As you turn the wheel to the left (yawing left), you feel pressure on your right butt cheek. You're skidding to the left. To correct for the skid, you need turn the wheel to the right (right rudder). If you fly gliders often, try to do more thermals to the right next time you go up. Practice makes perfect!
If the problem is altitude, remember what is happening aerodynamically. As you roll past 30° of bank, you're going to be losing a lot of the vertical component of lift, and you will need to apply more back pressure to maintain altitude. Don't wait for the airplane to descend; anticipate it and start correcting for it early. If you're in an airplane with side-by-side seats, remember that the sight picture is going to look differently from a left turn to a right turn. If you're sitting in the left seat, the nose of the airplane is going to appear to be higher above the horizon in a left turn than in a right turn. Some airplanes (like a C-310R) have significantly different sight pictures! In the glider, just track the nose right along the horizon all of the way around the turn. Again, practice rolling into and out of steep turns (360° in each direction), and be aggressive enough so that you can see where you may need improvement.
And one last thought: if you're adding a lot of power when
you roll into your steep turns, you will need significantly more
rudder when rolling into right turns to counter-act torque. Likewise,
when you reduce power when rolling out of the right turn, you
will need significantly more left rudder due to decreasing torque.
I hope I've answered the question you were asking, and I hope I was able to help.
Chris Fleming CFI/G, ATP
--Make the turn at stall speed + five knots based upon weight and POH.
--1.3 times stall speed takes larger turn radius.
---Practice the turn at altitude at stall speed to get height you need for turn-back.
--Allow four seconds for decision making
--On average use a 225-degree teardrop back and 45 degree alignment series
Conquering the Base to Final
As many of you know from my presence around here for the past 6 years, I will from time to time see something being discussed on the group that I feel can use some additional comment. But I feel that what I want to say might be a bit extensive for a simple in thread reply. The recent discussion on how much the airspeed increases in a skidding turn is such a situation. If you will bear with me, I'll discuss what I want to say here. I make it a habit never to say that the way someone is learning something is wrong. I'd rather just tell you the way I do something, or have taught other pilots to do something and let all of you make up your own minds. It is always my hope that you will try the things I suggest here and perhaps become a bit better or a bit smoother. The things I'm about to suggest to you have taken me all the way through my career.
When you fly high performance airplanes in the low altitude aerobatic display arena, or deal with ACM and test flying in the 3 dimensional fighter arena, you start learning how to fly an airplane a bit differently than you do in everyday life. Certain things reveal themselves as possibly standing out in need of correction, and as you get deeper into high performance flying, you adjust! You begin "smoothing out" your technique and discarding some of the very basic rote things you learned when you began training as a pilot. In other words, you improve your technique. To be blunt with you, if you don't improve your technique, and continue doing things completely by the book, you will simply die in these arenas.
Such is the case with skidding turns. One of these "adjustments"
that you make in your technique as you fly in the arenas I've described to you
is so subtle that it usually goes unnoticed. You just begin doing it
naturally, that is unless you also happen to be a flight instructor interested
in better ways of teaching student pilots to fly airplanes. In that case you
incorporate what you are doing into your basic training curriculum as I have
done for more years than I can remember. :-)
Now, let's revisit those skidding turns from base to final and take a slightly different approach to dealing with the situation. First of all, you all know the math. For a normal loaded turn, the stall speed increases as the square root of the load factor. But we're talking about skidding turns here aren't we, and in particular, the turn from base to final; and we're asking how much the stall speed increases in this skidding turn. Well, first of all, most base to final turns are descending, not level and under normal g, This usually means unloaded, so by the time we factor in this "unloaded" turn, and throw in a skid (excessive inside rudder and perhaps a bit of opposite aileron just to show the world how REALLY dumb we are. THEN factor in everything that an angular velocity for the relative wind in the skid might be doing to our pitot static system and Walla!!.....we can see that it's going to be REAL hard to nail down the exact IAS that the old puddle jumper is going to show us as we reach climax and depart most likely over the top.
Let's also assume shall we, that since we were stupid enough to allow all this to happen, we're also going to be surprised enough when it DOES happen. By the time we the inevitable involuntary reflex action that freezes our "first timers" hands and feet solid for those precious nano-seconds that we now no longer have to recover the airplane; that we in fact, may very well might have just bought the farm.
Now, this brings me finally to my point about all this. It's fine to use a
ball for checking the quality of the turn; and it's right as rain that you
should know that the stall speed increases with bank, but let me tell you
something about this, and it might surprise you. Pilots who fly airplanes in
maneuvering flight where perfect if not near perfect performance is not only
required, but a life saving necessity, usually DON'T use
a ball for turn quality!! Imagine for a moment, you are with me in a fighter
we're demonstrating as we flatten out of a half Cuban and sight up the show
line at 200 feet AGL. Now, as we establish the correct nose attitude for the
roll set we begin a roll to the left with left aileron and left rudder to offset the yaw. Almost immediately we have to switch to top rudder and go forward stick to pass through knife edge without dishing the nose. If we dish the nose, we're dead. There's no air under there to correct in time. Now we blend in forward stick and that top rudder into forward corner stick and neutral rudder as we reach exact inverted.
Now I won't take you all the way through this roll. I just wanted to make a
point here. (No, not a point roll :-) Notice that at no time during this
sequence did we even think about looking at the ball. We were watching the
When turn quality MUST be exact, you don't have to use a ball to check it. You keep your damn eyes out there in front of the nose. You draw an imaginary line with your eyes directly forward to the horizon, or a point directly in front of you, and you use the nose movement on the horizon or that point to give you INSTANT turn quality information without ever looking at the panel.
This is my point here gang. That nose out there directly in front of you paired with your own eyes is the finest ball you will ever see as long as you fly an airplane. If you are doing this correctly, ANY deviation from a
perfect turn entry and exit will be immediately apparent to you. The overall point here is "don't get bogged down in UNNECESSARY work when you should be SOLVING THE PROBLEM!!!......like worrying about what the airspeed will be at stall instead of FEELING the airplane.....and CORRECTING the error....NOW!
Here's an exercise to practice. I've been doing it all through my career and I have had every pilot I've ever taught to fly do it as well. You are going to do alternating turn entries, first one way, then the other, with a hesitation between them in level flight. These are NOT Dutch rolls! The amount of heading change isn't a consideration...it's random....just keep it around 30 degrees or so. The object is to roll into the turn while WATCHING THE NOSE.......stabilize.......Roll out the other way. Then repeat the exercise again and again. Do this with a safety pilot and clear when necessary.
Here's what you're looking for. Roll in fairly hard....left hand...left foot.....check the nose. IT SHOULD BE PINNED!!!!!! If the nose moves an inch to the right....you don't have enough inside rudder for the amount of aileron. If the nose moves left in yaw...you have too much inside rudder.
NOTE what you are either over controlling or under controlling and do it again, only this time correct what you did wrong the last time. Keep this up until you can roll into and out of these random turns with the nose ABSOLUTELY PINNED until you neutralize the bank. By doing this, and watching that nose, you will immediately see the quality of your turn entries and exits. Forget the damn ball! Get your head out of the cockpit and FEEL the airplane.
Now, what has all this to do with that skidding turn from base to final. Simple! After practicing this exercise, this base to final turn, if done INCORRECTLY, will be so IMMEDIATELY apparent to you, that long before you ever reach that increased airspeed you're worrying about; you will have seen and corrected the error, which is the ultimate and ONLY thing that should be happening in this situation. Hope this hasn't been too long winded and that it possibly might help some of you.
Remember; in this new instrument intensive environment that we all live in, it's important to know the math and watch the gauges, but never forget that if you learn attitude flying, and become proficient at hand flying the airplane using the multiple cues available to you in this environment, you will become much better pilots.
By Steve Seibel
Gene's Take On
A Very Close Analysis of Why It Is as It Is
Experiments in airplanes show P-factor and other factors will vary in left or right turns. The amount of slip indicated by ball displacement depended on how quickly the bank was entered up to 60 degrees. Adverse yaw is the primary cause of ball displacement you enter a turn. Slips and skids are caused by the tail failing to follow the nose
A cause of adverse yaw is when the opposite wings twist by wash in and wash out in the turn so as to produce differing drag to the relative wind. The wash in of the lowered wing changes the amount of lift. Likewise the raised wing’s lift is changed with more drag. The dominating factor of all this is the method by which the wings can be raised or lowered just by flying with the rudder.
Aircraft have inertia or resistance to movement in every axis. Even with perfectly balanced controls the inertial in the roll axis will create some side effects such as slips and skids during a roll input or recovery from shallow banks.
Changing seats in an airplane makes you notice that not only are you using different hands you are using different references to your instruments and a different reference for the nose location depending on whether you are sitting en the high or low seat during the turn. Just where you look greatly depends on your experience. The key from either seat is not to use the center of the nose as your aiming point.
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Continued on 3.25 Skids or Slips