Red Bull Air Race Tech Talk | Understanding the Stall

Aviation legend and Red Bull Air Race Technical Director, Jim ‘Jimbo’ Reed is back with another Tech Talk! This time it’s all about the stall, how it effects the raceplane, what happens and why! In the Red Bull Air Race every second counts and if a pilot stalls his wing during a high-G turn it can cost them a fraction of a second – that’s the difference between winning and losing!
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About: The Red Bull Air Race World Championship features the world's best pilots in a motorsports competition based on speed, precision and skill. Using the fastest, most agile and lightweight racing planes, Red Bull Air Race pilots navigate a low-level aerial race track made up of air filled pylons, flying at speeds reaching 230mph while withstanding forces of up to 10g. The objective is to complete the course, navigating the 65 feet high specially designed inflatable pylons known as Air Gates in the fastest possible time. Red Bull Air Race pilots must pass between the Air Gates in the correct position taking care not to touch them with their wings. The pilots compete for points at each Red Bull Air Race and the one who accumulates the most at the end of the season is crowned Red Bull Air Race World Champion.

[HighFlyer]

AoA is all you need to know. The wing stalling at low speed is because the AoA needs to increase to push more air downward. At high g loads such as the bottom of a loop angular momentum causes the weight side of the lift=weight equation to increase. This requires an increased AoA leading to a stall. With a contaminated wing surface the contamination causes disturbances in the boundary layer which is able to separate from the wing at a shallower AoA. But again it's the Angle of Attack that is the cause of the stall. Low speed, high g loads and airfoil contamination are just the reason for the increased AoA.

[guywholikesplanes]

The roll angle also increases stall speed. You are more likely to stall while turning than while flying straight