The Alpha Principle

Loss of control in flight (LOC-F) is implicated in 51 percent of all fatal personal and business-use GA accidents, according to the NTSB. The preponderance of LOC-F events are aerodynamic stalls, according to NTSB member Dr. Earl Weener and as reported in his presentation at AOPA Summit in October 2012. Notably, fatal stalls are less common in instructional flight, perhaps because pilots are expecting them when training, and the instructor helps detect and respond to them. In my almost 30 years of experience, stalls and stall avoidance are constantly emphasized and feature regularly in NTSB investigations. I suspect a lot of Aviation Safety readers have even more experience than me, and have seen the same emphasis and crash record even longer.

Key Takeaways:

• Fatal Loss of Control in Flight (LOC-F) accidents, primarily stalls, are often due to pilots misunderstanding that stalls are caused by exceeding critical Angle of Attack (Alpha), not just low airspeed or a nose-high attitude.
• Stalls can occur at any airspeed or pitch, even nose-low (e.g., during a go-around), with increased G-loads (like in banked turns) causing the wing to reach critical Alpha at higher indicated airspeeds.
• Pilots must understand that stalling requires back pressure on the controls, and recovery involves releasing this pressure; uncoordinated flight drastically increases the risk of an asymmetric stall and spin.
• To effectively avoid stalls, pilots should focus on visualizing and managing Alpha, ensuring good rudder coordination, and regularly practicing high-Alpha maneuvers (slow flight) to internalize necessary control inputs.

Key takeaways sponsored by Aviator Pro | Start Your Training ->

See a mistake? Contact us.