In this lesson, you will learn how an aircraft spin develops, recognize the incipient and fully developed phases, understand the aerodynamic forces involved, and learn the correct spin recovery procedure. You will also learn how to recognize and avoid conditions that can lead to an unintentional spin. This lesson builds directly on the stall recognition and recovery skills covered in Stall Recovery .
A spin develops when an aircraft is stalled while yaw is present. Understanding the phases of a spin helps you recognize the condition early, prevent an unintentional spin and apply the correct recovery principles.
Learn to recognize the combination of stall, yaw and autorotation that marks the beginning of an incipient spin.
Follow the progression from the incipient phase to a fully developed spin and understand what changes as the rotation becomes established.
Learn the sequence of control actions used to stop the rotation, break the stall and return the airplane to controlled flight.
Recognize situations where low airspeed, excessive angle of attack and uncoordinated flight can combine to create a serious spin risk.
An aircraft spin is a stalled flight condition in which the airplane descends while rotating around a near-vertical axis. The airplane follows a steep, rotating downward flight path until recovery action is taken.
During a spin, the airplane remains stalled while continuing to rotate and lose altitude. This combination of stall, rotation and descent distinguishes a spin from normal turning flight.
A spin is a stalled condition. The airplane remains beyond the normal controlled flight condition associated with an unstalled wing.
The airplane rotates continuously rather than simply entering a normal banked turn.
A spin produces a steep descending flight path, making altitude an important factor in recognition and recovery.
For a spin to develop, the airplane must first be stalled while yaw is present. The yaw creates different aerodynamic conditions on the two wings, causing one wing to become more deeply stalled than the other. The resulting differences in lift and drag create the rolling and yawing motion that develops into autorotation.
A spin cannot develop in normal unstalled flight. The wing must first reach or exceed its critical angle of attack. A stall by itself, however, does not necessarily produce a spin.
When yaw is present as the airplane stalls, one wing moves downward while the other moves upward. The wings therefore meet the relative airflow differently and become stalled by different amounts.
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As rotation begins, the downgoing wing meets the relative airflow at a greater angle of attack and becomes more deeply stalled. The upgoing wing meets the airflow at a lower relative angle of attack and remains less deeply stalled. The two wings therefore produce different amounts of lift and drag.
The downgoing wing operates at the greater angle of attack. It produces less lift and more drag. Reduced lift allows the wing to continue dropping, while the additional drag strengthens the yaw.
The upgoing wing meets the relative airflow at a lower angle of attack. It therefore remains less deeply stalled and produces relatively more lift and less drag than the downgoing wing.
The aerodynamic imbalance reinforces itself. The downgoing wing produces less lift and continues to fall, while its greater drag increases the yaw in the direction of rotation.
At the same time, the upgoing wing remains relatively less stalled and continues to produce more lift. The rolling and yawing tendencies therefore reinforce one another, producing the continuing rotation known as autorotation.
The wing continues downward and strengthens the yaw.
The difference between the two wings maintains the rolling imbalance.
Roll and yaw reinforce each other as the airplane continues its rotating descent.
Some airplanes may show a tendency to drop a wing as the stall develops. A wing drop alone is not necessarily a developed spin. However, if the airplane remains stalled while yaw continues, the motion can develop into autorotation.
The phases of a spin describe how the airplane progresses from the initial stall and yaw into established autorotation and, finally, recovery. The four phases are entry, incipient, developed and recovery. Understanding the differences between them helps a pilot recognize how the spin is changing.
During the entry phase, the airplane reaches the stall while yaw is present. The aerodynamic imbalance between the wings begins, but established autorotation has not yet developed.
Entry may be intentional during approved spin training or accidental when an airplane is stalled while uncoordinated.
The incipient spin begins when the airplane has stalled and rotation starts. It continues until the spin becomes fully developed.
During this phase, aerodynamic and inertial forces have not yet reached equilibrium. Airspeed remains low while the rate of rotation and vertical speed continue to change.
In a fully developed spin, the airplane's rate of rotation, airspeed and vertical speed become relatively stabilized.
Aerodynamic and inertial forces are approximately balanced, producing a self-sustaining rotating descent. The flight path is steep and altitude continues to decrease rapidly.
The recovery phase begins when the appropriate anti-spin control inputs disrupt the established spin and the rotation begins to stop.
The angle of attack is reduced below the critical angle, the wings regain normal lift, and the airplane transitions from the rotating descent toward normal controlled flight.
During the incipient phase, the spin is still developing. The rotation rate, vertical speed and aerodynamic forces have not yet reached the relatively stable condition of a fully developed spin.
This is why early recognition is so important: the airplane has already stalled and begun to rotate, but the spin has not yet reached its developed equilibrium.
Intentional spin training must only be conducted in an aircraft approved for spins and within the aircraft's weight-and-balance and operating limitations. Always follow the specific procedures and limitations in the aircraft's AFM/POH and the guidance of a qualified flight instructor.
Once the pre-maneuver checks are complete, establish the airplane for the spin entry and progressively bring it to the stall. At the stall, use the required rudder and elevator inputs to initiate rotation. The following sequence describes a typical training spin entry; always use the aircraft's POH/AFM procedure if it differs.
Complete the full pre-maneuver check before beginning the spin entry. Confirm sufficient height, a suitable area, aircraft security, engine condition and a thorough lookout for traffic.
Need a detailed review of every HASEL item? Review HASEL and clearing before stall practice →
Begin from straight-and-level flight on the selected heading. Stabilize the airplane before starting the deceleration. Apply carburetor heat if required by the aircraft procedure.
Reduce power to the setting specified for the airplane and training exercise. Some aircraft use idle power, while others require a specified RPM during the entry. As the airplane slows, progressively increase back pressure to raise the nose and continue increasing the angle of attack toward the stall.
As the airplane approaches the stall, keep the ailerons neutral. Do not attempt to initiate or correct the developing roll with aileron unless the aircraft-specific procedure states otherwise.
As the stall occurs, apply the rudder input specified for the entry in the desired direction of rotation while applying or maintaining the required back elevator. Use the control positions specified for the training aircraft.
Maintain the prescribed entry controls as the wing drops and rotation begins. Keep the ailerons in the position specified by the aircraft procedure. The airplane is now entering the incipient spin.
Do not assume that every airplane uses idle power or exactly the same control positions for spin entry. The required power setting may be idle or a specified RPM, and the exact entry technique can vary between aircraft. The POH/AFM and instructor procedure take precedence.
Once spin recovery is initiated, make the required control inputs promptly and in the correct order. For many training airplanes, the common recovery sequence can be remembered with the mnemonic PARE: Power, Ailerons, Rudder, Elevator. Always follow the aircraft's POH/AFM if its procedure differs.
Move the throttle to idle. Power can aggravate the spin and may increase the rate of rotation or flatten the spin.
Place the ailerons in the neutral position. Do not attempt to stop the rotation with aileron. Aileron input can alter the spin characteristics and may delay recovery.
Apply and hold full rudder opposite to the direction of rotation. The input should be positive and prompt.
Immediately after applying opposite rudder, move the elevator forward as required to reduce the angle of attack and break the stall. Do not wait for the rotation to stop before applying the elevator input.
Hold the opposite rudder and required forward elevator while keeping the ailerons neutral until the rotation stops.
As soon as the rotation stops, neutralize the rudder. Leaving opposite rudder applied as the airplane accelerates can produce unwanted yaw or sideslip.
Once the spin has stopped, the airplane will normally be in a nose-low attitude and airspeed will begin increasing. The recovery is not complete until the airplane is returned smoothly to controlled flight.
Apply progressive back elevator pressure to recover from the dive without creating excessive load factor.
Airspeed can increase rapidly once the rotation stops. Recover smoothly while respecting the aircraft's limitations.
Restore power as appropriate once the airplane is recovering and return to the desired flight condition.
Excessive back pressure after the rotation stops can increase the angle of attack enough to produce another stall. Recover smoothly while respecting the aircraft's airspeed and load-factor limitations.
PARE is a useful memory aid for the general recovery sequence used in many training airplanes, but it is not a substitute for the aircraft's approved spin-recovery procedure. If the POH/AFM specifies different control inputs or a different sequence, follow the manufacturer-approved procedure.
Continue your spin training with a dedicated course covering spin awareness, recognition and recovery techniques for pilots.
View the Spin Awareness Course →An unintentional spin is most dangerous when it develops close to the ground, where there may be insufficient altitude for recovery. Good spin prevention therefore depends on recognizing the situations in which airspeed, angle of attack and coordination can deteriorate quickly.
During a low-speed climb, the airplane is already at a relatively high angle of attack. Entering a turn increases the demand on the wing and may allow airspeed to decrease further if pitch is not adjusted.
After an engine failure during the initial climb, airspeed can decay rapidly if the climb attitude is maintained. An aggressive or poorly coordinated turn at low speed can further increase the risk of a stall and spin.
Sloping terrain, ridgelines or other visual features can create a misleading horizon and make it harder to judge pitch and bank accurately. Airspeed may decrease without being immediately obvious.
If the airplane overshoots the extended runway centreline during the base-to-final turn, there can be a strong temptation to use extra rudder to bring the nose around while holding the bank with opposite aileron.
At low airspeed, that skidding, cross-controlled condition can produce a rapid stall and spin entry with very little altitude available for recovery.
The base-to-final cross-control scenario is explained in more detail in Turning Stalls, Cross-Control and Base-to-Final Risk →
Not every airplane spins in exactly the same way. The attitude, rate of rotation and recovery characteristics can change with the power setting, aircraft loading, configuration, control position and density altitude. This is one reason spin procedures and limitations must be learned for the specific airplane being flown.
Propeller and engine effects can influence yaw, pitch attitude and rotation. In some airplanes, power can make the spin flatter or increase the rate of rotation.
Do not assume that a power-on spin will behave like a power-off spin. Use only the configurations and procedures approved for the airplane.
Both aircraft weight and the distribution of that weight affect stability and control response. Of particular importance is the location of the centre of gravity.
Being within the aircraft's approved weight and balance envelope is essential. Spin approval may also have more restrictive loading limits than normal flight.
Flap position and the position of the ailerons, elevator and rudder can change the aerodynamic forces acting on the airplane and therefore change its spin characteristics.
Never assume that a configuration approved for normal flight is approved for intentional spinning. Check the POH/AFM limitations before the exercise.
Changes in air density affect aerodynamic forces and aircraft performance. The FAA identifies density altitude as one of the factors that can influence the type and characteristics of a spin.
Do not expect identical handling or recovery characteristics simply because the same airplane and entry technique are being used.
As the centre of gravity moves aft, longitudinal stability decreases and less elevator force may be required to reach a high angle of attack. An excessively aft loading condition can also result in more difficult spin recovery and may contribute to a flatter spin. Never conduct intentional spin training outside the approved loading limits.
A spin produces rapid changes in attitude and continuous rotation that can make orientation difficult. During the maneuver, the information coming from your eyes, inner ear and body sensations may not agree. Understanding this helps prevent misleading sensations from interfering with the correct recovery actions.
During rotation, the ground and horizon move rapidly through the pilot's field of view. Maintaining an accurate sense of attitude and movement can therefore become more difficult.
The semicircular canals sense changes in rotational movement, but they do not provide a perfectly reliable indication of aircraft attitude or continued rotation.
Forces acting on the body during a maneuver can create powerful sensations of movement or position that do not necessarily match the airplane's actual attitude.
The nose-low attitude, rotation and changing view of the horizon can make the maneuver appear much faster or more confusing than expected.
This is another reason to know the aircraft's recovery procedure before beginning spin training rather than trying to work it out during the maneuver.
A strong sensation of turning, banking or pitching does not necessarily provide an accurate picture of what the airplane is actually doing.
Unexpected sensations can lead a pilot to delay, reverse or incorrectly modify the required recovery control inputs.
When rotation stops, movement of fluid within the semicircular canals may continue temporarily. This can produce a false sensation of rotation or even a sensation that the airplane is turning in the opposite direction. Do not reapply control inputs simply to correct a sensation that is not confirmed by reliable references.
Apply the approved spin-recovery sequence rather than changing the controls in response to unexpected body sensations.
Use reliable outside and instrument references as appropriate to determine whether rotation has stopped and to establish the actual aircraft attitude.
Once rotation has stopped, neutralize the required controls and recover from the resulting dive smoothly rather than chasing misleading sensations.
Intentional spin training should be conducted only in an aircraft approved for spins, within its operating limitations, and with the appropriate flight instruction. Familiarity with the expected sensations and sight picture reduces the chance that surprise or disorientation will interfere with the recovery.
Check that you understand how a spin develops, how to recognize the different phases, how to enter and recover from a training spin, and how to avoid an unintentional spin. Try to answer each question before opening the answer.
These eight questions cover spin aerodynamics, phases, entry, recovery, aileron use, spin prevention, loading and disorientation.
In a stall, the wing has exceeded its critical angle of attack. In a spin, the airplane is also rotating because the two wings are experiencing different amounts of stall, lift and drag.
The airplane must be stalled and there must be sufficient yaw or asymmetry for one wing to become more deeply stalled than the other. This produces the autorotation characteristic of a spin.
Entry creates the stalled and yawing condition. The incipient phase begins as autorotation develops. In a developed spin, the rotation becomes more established. Recovery begins when the required anti-spin controls are applied.
Confirm sufficient height, a suitable area, aircraft security, engine condition and lookout. Then establish the airplane and use the specific entry procedure required for the training aircraft.
The commonly taught sequence is: power idle, ailerons neutral, full rudder opposite the direction of rotation, then elevator forward to break the stall. The aircraft's approved POH/AFM procedure always takes precedence.
Aileron deflection changes the angle of attack and drag on the wings and may deepen the stall on one wing or delay recovery. In the standard recovery used by many training airplanes, the ailerons are therefore neutralized.
Do not force the airplane back toward the runway with excessive rudder and opposite aileron. A low-speed skidding turn close to the ground can rapidly produce an uncoordinated stall and spin.
Rotation affects the inner ear, and a false sensation of continued or opposite rotation may remain even after the spin has stopped. Follow the approved recovery procedure and use reliable visual and instrument references rather than reacting to sensation alone.
Before practicing spins, you should be able to explain why a spin develops, identify its phases, describe the approved entry and recovery procedure for your aircraft, and recognize the situations most likely to produce an unintentional spin.
