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The Incipient Spin is a term assigned to the transition phase during which a stall is propagating towards a developed spin. The recovery from an incipient spin prior to reaching one-turn is shown in the video below. This is for demonstration purposes only and should only be attempted in a spins-approved aircraft.
Our goal as a pilot when faced with a stall, including slipping or skidding cross-controlled and accelerated stalls, is to immediately and correctly apply the Stall Recovery Procedure. The application of the Stall Recovery Procedure is our first line of defense in recovering the aircraft to normal flight (i.e. Angle of Attack (AOA) less than Critical AOA). If the aircraft is uncoordinated at the stall and this yaw-roll couple / uncoordination is allowed to develop while sustaining the stall, the aerodynamics being experienced by the aircraft will eventually drive the aircraft towards a different stabilized flight condition called The Spin. We need to stop the spin before it starts and the Stall Recovery Procedure is how to do it.Although every stall does not result in a spin, it is important to recognize that every spin is always preceded by a stall. If we can “fix” the stall when it starts, we save ourselves the drama of having to deal with the spin. Note: Once in a developed spin, the aircraft will not respond favorably to the Stall Recovery Procedure. When faced with a developed spin the pilot should immediately apply the Spin Recovery Technique in the hopes of recovering from the spin, if it is recoverable at all.
At what point do we make the decision to stop applying the stall recovery and revert to the spin recovery? That is an excellent question and the answer really depends upon the type, category and stall characteristics of the aircraft in question. For example, normal and utility single-engine certified aircraft must demonstrate recoverability from a one-turn spin (or a 3-second spin, whichever takes longer) in not more than one additional turn, but that’s it. After one-turn, there is no guarantee the aircraft is recoverable at all unless it is certified for spins. The vast majority of large multi-engine aircraft are not recoverable from the spin because the pro-spin inertial forces generated in the developed spin for these aircraft exceed the pilot’s ability to generate sufficient anti-spin force to “de-couple” auto-rotation to return to normal flight. In these aircraft, it may be that the only option available is the Stall Recovery Procedure and the only portion of the stall that offers a recovery option is the initial stage. The earlier the Stall Recovery Procedure is correctly applied in the stall, the more likely the possibility of a recovery.
STALL RECOVERY PROCEDURE
An example of a stall recovery for most general aviation aircraft and most other aircraft types and classes is as follows:
- PUSH: Reduce AOA (forward movement of the control column) to allow the wing to reduce AOA below critical AOA, reduce drag and to immediately transition from stalled fight to normal unstalled flight. Common tendencies are to either over-push causing excess nose drop below the horizon increasing altitude loss or a fore-aft pumping motion of the yoke causing one or more secondary stalls.
- POWER: Smoothly add up to full power (usually) to increase airspeed and minimize altitude loss. We can do stall recoveries all day with the power at idle, however, an idle power setting is not assisting us in minimizing altitude loss. Keep in mind that there are certain situations that selecting power to idle in the stall recovery is the proper action. Examples include high-torque single-engine prop aircraft and in a Vmc situation in a multi-engine aircraft.
- RUDDER: If there is any roll/yaw motion associated with the initial stall and the wing is still at or beyond critical AOA, the rudder should be used to stop the yaw-roll couple from developing. The amount of rudder used is only enough to coordinate the flight condition and should be accomplished in one application. Pumping or cycling the rudder is not a desirable technique especially for large aircraft. Note that the rudder is not used to roll the aircraft wings-level in a stall recovery. Common errors in the use of rudder vary from not using it all to using it far too much, for too long. Rudder is critically important in an uncoordinated stall condition (such as a cross-controlled stall) to ensure the stall is not allowed to develop from a stall to a spin.
- ROLL: When the wings are clearly unstalled and coordinated flight has been regained. The aircraft’s flight attitude must be immediately be re-oriented to a wing’s level condition by rolling with aileron and coordinated rudder to the nearest horizon. Again, the aircraft should not be rolled by use of rudder alone at this stage. The primary roll control in normal flight is through the proper use of ailerons.
- CLIMB: With the wings level in coordinated flight, aft yoke movement should be immediately applied to initiate recovery to a climbing attitude. The amount of elevator movement applied must ensure the aircraft remains below critical AOA at speeds below Va and at a load less than the limited load factor of the aircraft at speeds above Va.
Essentially, the first three steps of the stall recovery (1-2-3) are directly focused on safely recovering the aircraft from the stall and the last two steps (4-5) are to recover from any resulting unusual attitude. It is important for the pilot know and understand that these processes can not be successfully reversed. The stall must be solved first, regardless of the flight attitude of the aircraft, then followed by solving the unusual attitude.
Please take a moment to have a look at the demonstration below to see how the Stall Recovery effectively recovers the aircraft prior to completing one-turn of rotation from a cross-controlled slipping turn stall entry. This only applies to a Normal category aircraft (and should only ever be attempted in a Spins-Approved aircraft such as and Aerobatic aircraft) – emphasis in all practical training should be for the stall recovery to be applied at the first indication of the stall in all aircraft. If you prefer to look at a more detailed discussion on the recovery from a skidded turn stall entry, then please refer to our newsletter on the Skidded Turn Traffic Pattern Stall. In the meantime, please have a look at this one … we look forward to hearing your comments in the form below.