A cross-controlled stall close to the ground can be a terrifying occurrence if you don’t take the right precautions. Here’s how to prevent such a situation from happening to you.
Where’s the Risk? Your Final Two Turns in the Traffic Pattern
Your risk of a cross-controlled stall is most likely to occur during your downwind-to-base and base-to-final turns. If you overshoot the runway, your natural instinct might be to increase your bank to get back on final. But what follows can go awry. Pilots often realize their bank is too steep, but they need to keep the airplane turning, so they decrease the bank and step on the rudder to maintain a high turn rate.
The problem with a cross-controlled maneuver like this is that you’re skidding the plane, and if a stall occurs, it’s highly likely that you’ll enter an incipient spin. And if the spin fully develops so close to the ground, your chances of recovery are slim, regardless of your piloting skills. There simply isn’t enough altitude to recover.
What Causes a Cross-Controlled Stall?
Cross-controlled stalls happen when the critical AOA (angle of attack) is exceeded with aileron pressure applied in one direction and rudder pressure applied in the opposite direction. This results in uncoordinated flight. You’ll notice the ball on your turn coordinator swing to the outside of your turn, and you might feel that “seat of your pants” sensation of falling to the side of your seat.
A skidding cross-controlled stall is most likely to occur during a poorly executed base-to-final turn when you overshoot the runway’s centerline and try to correct back to the centerline by increasing the bank angle. While doing this, you’ll be increasing back pressure on the elevator and applying rudder in the direction of the turn to bring the nose around to align with the runway centerline.
“The difference in lift between the inside and outside wing will increase, leading to an unwanted increase in bank angle. At the same time, the nose of the airplane slices downward through the horizon” (FAA). Many pilots have the natural reaction to pull back on the elevator control, further increasing the AOA towards your critical AOA.
Why CFIs Demonstrate Cross Controlled Stalls
A cross-controlled stall is a maneuver performed by a flight instructor for their students, with the exception of CFI applicants who may have to do it during a practical test. The purpose of this maneuver is to show students the effects of uncoordinated flight on stall behavior while emphasizing the importance of maintaining coordinated flight during turns. Understanding how to recognize, prevent, and recover from a cross-coordinated stall is crucial for all pilots, especially at low altitudes during a base-to-final turn.
If you’re a CFI planning to demonstrate a cross-controlled stall, here are some tips from the FAA’s Airplane Flying Handbook: Before performing this stall, ensure you have a safe altitude for entry and recovery in case of a spin and clear the area of other traffic while slowly retarding the throttle. Next, lower the landing gear (if equipped with retractable gear), close the throttle, and maintain altitude until the airspeed approaches the normal glide speed. To avoid exceeding the airplane’s limitations, don’t extend the flaps. While establishing the gliding attitude and airspeed, retrim the airplane. Once the glide is stabilized, roll into a medium-banked turn to simulate a final approach turn that overshoots the centerline of the runway.
During the turn, smoothly apply excessive rudder pressure in the direction of the turn while holding the bank constant by applying opposite aileron pressure. At the same time, increase back elevator pressure to keep the nose from lowering. All these control pressures should be increased until the airplane stalls. When the stall occurs, recover by applying nose-down elevator pressure to reduce the AOA (angle of attack) until the stall warning disappears, remove the excessive rudder input, and level the wings. Apply power as needed to return to the desired flight path.
Preventing and Recovering From Cross-Controlled Stalls
The best thing you can do to avoid a deadly stall like this is to anticipate the winds in the traffic pattern and maintain an appropriate distance from the runway. On the downwind leg, note the wind direction and make sure you give yourself enough room for a base-to-final turn. If you overshoot the runway centerline, maintain a coordinated bank to get back on the extended centerline of the runway.
If you overshoot to the point where you don’t think you can get back on centerline and restabilize your final approach, perform a go-around and try again.
Finally, if you encounter a cross-controlled stall close to the ground, your primary focus should be on preventing a spin. Reduce the AOA until the stall warning disappears. Coordinate with the rudder and level your wings as you fly out of the incipient stall.
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