Technique: Accelerated stalls
Banking and yanking
Load factor
When an airplane turns, its load factor, or airframe stress, increases. That’s the feeling of being pulled down harder in the seat. Regardless of the type of airplane, the load factor increases at a predictable rate. At 45 degrees of bank in a level turn, for example, the load factor is 1.4, meaning gravity will feel 40 percent stronger.
The biggest impact of load factor is on stall speed. It increases at the square root of the load factor. A 45-degree bank increases stall speed by 18 percent, and a 60-degree bank increases it by 40 percent!
Coordination
As with the approach and departure stalls we commonly practice, being coordinated helps immensely with accelerated stall recovery. If the rudder isn’t coordinated, the nose won’t fall to the natural, central position. Too much rudder on the inside of the turn will cause a spin, and it will happen quickly. Even outside rudder can lead to a spin, although not as easily. One reason traffic pattern stalls are often unrecoverable is because the airplane frequently wasn’t coordinated.
Test standard
Private pilots don’t have to demonstrate accelerated stalls on the practical test, but the Private Pilot Airman Certification Standards lists them in both the knowledge and risk management sections of steep turns and power-on stalls. That means an examiner will expect the applicant to be aware of accelerated stalls, know when and why they happen, and be able to describe how to avoid accelerated stalls and recover from them.
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