Airplane Spin Phases

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A spin is not a static maneuver; instead the plane moves through several distinct phases with the characteristics of the spin changing in each phase. The four phases are spin entry, incipient spin, developed spin, and spin recovery. Other books may use other names, but the basic concepts documented during each phase of the spin are still the same.

Spin entry phase
The spin begins as the plane stalls and the rolling/yawing motions begin. The nose of the plane normally drops well below the horizon as the spin begins to take effect. To enter a spin, first slow the airplane, just as with a stall. As the plane stalls, make sure the elevator control is fully aft, assuring a complete stall, then push full rudder in the direction you want to spin. For example, if you want to spin to the right, push full right rudder and hold it there. This will cause the plane to enter the second phase of the spin, the incipient phase.

Normal spin entry is made from a power-off, flaps-retracted stall. Before beginning the maneuver, fly clearing turns to the left and right, paying particular attention to the airspace below. You could lose several thousand feet of altitude, so it is important to make sure there are no aircraft below that could pose a safety concern. A photographic sequence of events follows: 
Figure shows the view looking out the left window from the pilot’s seat. The angle of attack is very apparent in this view. As the plane stalls, the ailerons should be in the neutral position and maintained in that position throughout the course of the spin. If the ailerons are turned into the spin, or away from the spin, they could cause a significant change in its characteristics. The rudder should be briskly applied, and the elevator should be moved to the full aft position if it is not already there.

Figure depicts the forward and left views of a spin as it progresses. As you can see, the change in pitch as the plane enters the spin is dramatic. The plane used in this photo sequence has a tendency to roll slightly inverted as it first enters the spin, then it settles down into a steep nose-down attitude as the spin develops. The steep nose-down angles and rapid rate of rotation can be disorienting to many pilots new to spins. Once the spin begins and the nose is pointed at the ground, the section lines, trees, or roads are the best ground reference that the pilot has to maintain orientation. Keep the ailerons in a neutral position, the stick or control yoke fully back, and full rudder toward the direction of spin rotation in. Changing these control inputs will also change the spin.

Insufficient backpressure on the elevator control can prevent the plane from stalling cleanly and getting a good break as the stall takes place. This can make it more difficult to get the plane to enter a spin.

Using ailerons relates to the insufficient elevator backpressure situation. As students attempt to force the plane into the spin while it mushes along, they frequently roll aileron in, thinking their use will help things along. This can cause the plane to spiral, which looks similar to the spin but is a completely different maneuver.

Use of less than full rudder, briskly applied as the plane stalls, may prevent the plane from cleanly entering the spin. A common reaction from the plane is that it yaws in the direction of the rudder input but never really breaks cleanly and enters the spin. Do not be overly forceful in the rudder input, but be authoritative in its application and you will get a nice, clean entry into the spin.

If power is carried into a spin, it can cause the nose of the plane to rise, putting the plane into a flat spin mode —this can be very dangerous. Always be certain that power is at idle when you stall the airplane and plan to enter a spin. If you should happen to inadvertently carry power as you enter the spin, immediately reduce it to idle.

Like unplanned stalls, the purpose of learning to do spins is to be able to recognize the potential for a spin and how to avoid it. Then, if that should fail, how to recover from it as rapidly as possible. Almost without exception, pilots who are exposed to spins for the first time have a strong tendency to pull back on the control yoke, trying to raise the nose —exactly opposite of what is required. Although most pilots could read this and assume they are well informed for spin recovery, there is no substitute for experience and practice.

If you should happen to accidentally enter a spin, determine which direction the plane is spinning before you make rudder input. Directly over the nose of the plane is the best location to look to figure out whether the plane is spinning to the left or right. If you are so disoriented that you can’t tell which way the plane is spinning, step on the rudder pedal that has more resistance. The difference in airflow over the rudder can make the rudder pedal that would be used for spin recovery more resistant to movement. And if using that rudder pedal fails, try the other one.

Incipient spin phase
The incipient phase of the spin takes place as the plane transitions from forward flight to the nose-down, rolling, yawing descent present in a spin. Inertia, lift, drag, and yaw all affect the plane during the incipient phase. In fact, NASA has expended a great deal of time and resources studying spins and what factors affect them.

It generally takes approximately two turns for the plane to make the transition from horizontal to vertical flight path. Due to the tendency of a plane to want to continue in its original motion, in many cases it is easier to recover from a spin while the plane is in the incipient phase. In fact, while not an approved method of recovery for most aircraft, letting go of the controls while the plane is in the incipient phase can often result in the plane recovering from the spin on its own. DO NOT assume this is the case for the plane you are flying and go off and practice spins without competent instruction. Selftaught spins are not recommended for anyone. At the end of the incipient phase, the plane’s momentum has transitioned into a fully developed spin, and it is much less influenced by the forces originally acting on it during spin entry.

Developed spin phase
The developed phase of a spin is not an unchanging situation. The plane actually goes through cyclical periods as part of the developed phase. The changes here include differing pitch attitudes and rates of spin rotation—oscillations in nearly every axis. For example, the Pitts Special S-2B has a tendency to be nose low at the 180-degree point of the spin, and the nose is higher at the 360-degree point.

Every plane is different in the way it reacts during the developed spin phase. Some airplanes will have a more nose-down tendency during the spin, while others may have faster rotation rates. Depending on how you enter the spin and apply controls, the same plane may behave differently from spin to spin. The center of gravity can also affect the spin characteristics of a plane. Generally, the more aft the center of gravity is, the flatter the spin will be.

Spin recovery phase
The recovery phase of the spin begins when you apply correct flight control inputs that stop spin. It may take several turns from the point the spin recovery begins before the spin is finally over. It is very important that you know whether your plane is reacting correctly.

According to the FAA, the proper spin recovery technique is as follows:
1. Retard power.
2. Apply opposite rudder to slow rotation.
3. Apply positive forward elevator movement to break stall.
4. Neutralize rudder as spinning stops.
5. Return to level flight.

If the operations manual for your plane lists a different set of procedures to recover from the spin, use those rather than those listed here. Generally, the plane reacts immediately, recovering from the spin in less than one turn if the control inputs are correctly applied.

Figure shows a pilot taking these steps to recover from a spin. We have already indicated that a plane can take several turns to recover from a spin AFTER the correct control inputs have been applied. Many pilots become concerned if the recovery control inputs do not immediately produce a recovery from the spin, and they attempt other inputs, prolonging the time and altitude lost before they actually stop the spin.

The rudder input opposite the rotation of the spin should be brisk and to the full limit of the rudder travel. This input stops the yawing motion of the plane and ends the rotation of the spin. The forward application of elevator reduces the angle of attack and breaks the stall. The amount of elevator input necessary and the briskness of the input will vary from plane to plane. For many aircraft, a small forward movement is enough to break the stall, while with others it will be necessary to get the elevator control forward of neutral before the angle of attack is reduced to below the critical angle of attack. Keep the ailerons neutral as you recover; it is not uncommon for pilots to roll in ailerons in the same direction as the counter spin rudder input. This can aggravate the stall, making it more difficult to recover from the spin.

Once the spin is stopped and the rudder is neutral, ease the nose of the plane back to level flight. Avoid being overaggressive on the nose-up elevator input; like stall recovery, this can result in a secondary stall. At higher airspeeds, excessive use of the elevator can result in higher g-loads on the plane and damage the airframe, not to mention making for an uncomfortable recovery.

Spins can be disorienting to pilots who are new to them, especially the recovery phase of the spin. They have just had the plane pitch nose down and begin to rotate as they watch the terrain below spin crazily about the nose. When it comes time to begin the recovery, the pilot is often more than ready to exit the spin, and he or she applies the recovery controls in an aggressive, and sometimes counterproductive, manner. After a little practice, most pilots begin to feel more comfortable practicing spins and settle down as they make control inputs during recovery. But during the first few spins, a number of common errors seem to come to the surface.

The first error is incorrect order of application of the controls. One pilot knew spin recovery required power-off, full opposite rudder and forward elevator control input, but he figured the order didn’t matter. The order he wanted to use reversed the rudder and elevator steps, which can result in an accelerated spin. Improper order of the steps could prevent recovery or even make the spin worse.

Partial rudder input opposite the direction of the spin, or slow input of the rudder, can slow the recovery from the spin. Make sure you take the rudder pedal right to the stop. Once rotation has halted, you must then remember to neutralize the rudder pedals. Many pilots will forget to center the rudder after the spin stops, and the plane begins to yaw in the opposite direction as a result of the continued rudder input. This can result in the plane entering a spin in the opposite direction of the one it just recovered from.

Many pilots use an excessive amount of forward elevator as they break the stall. Use the minimum forward elevator needed to break the stall. Additional elevator actually increases the rate of descent and the loss of altitude. Figure shows the altitude lost during one, two, and three-turn spins, comparing the loss between a Cessna 152 and Pitts Special S-2B. These are for comparison only and should not be considered indicative of the altitude those model aircraft will lose in a spin. Notice that a one-turn spin results in a 600-to 800-foot loss of altitude. If in the pattern, you don’t have much room to recover if you actually get into a spin. Excessive forward elevator pressure as you recover could mean the difference between having or not having a successful recovery.

Once pilots have stopped the spin and broken the stall, they often pull back on the elevator control too rapidly or with too much force as they attempt to get back to straight-and-level flight. Use the elevator with authority, but do not overreact and cause an accelerated stall during spin recovery. At the other end of the spectrum, some students do not pull out of the dive after spin recovery quickly enough. Not only does this cause additional altitude loss, but also it allows the airspeed to rapidly build. If left unchecked, Vne can be reached very quickly, again with the potential for structural damage.

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