Stalls at “Any Attitude, Any Airspeed”

Every pilot learns that a wing can stall “in any attitude and at any airspeed.”

But it’s difficult to demonstrate that principle in a typical training aircraft. This video of an exercise that I do with my stall/spin/upset recovery students shows the value of training in an aerobatic aircraft.

I fly a basic loop, but at several points during the maneuver, I intentionally increase the angle of attack by pulling back abruptly on the stick. Each time I pull, the angle of attack quickly reaches the critical angle of attack, and the airplane shudders in an accelerated stall, regardless of the airplane’s airspeed or pitch attitude relative to the horizon.

In other words, you can change the airplane’s attitude (and its angle of attack) almost instantly, but changing its flight path requires more time. That difference between the attitude and the flight path is angle of attack, and when that angle exceeds the wing’s critical angle of attack, the wing stalls.

It’s also helpful to remember that a loop is just a vertical turn. The same principle applies when you bank the wings and turn an airplane in the horizontal plane. If you pull back on the yoke or stick during a turn, you increase the angle of attack. Pull back too aggressively, and the wing will reach its critical angle of attack and stall, regardless of the indicated airspeed.

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