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Hi folks,

I just saw this video on VansAirForce demonstrating uncoordinated turns near stall leading to spins. I found it particularly vivid, and the instructor did a great job of explaining what was going on:

https://www.facebook.com/eddie.seve/pos ... 700399316/

This is the original thread on VAF by the poster:

http://www.vansairforce.com/community/s ... p?t=137823

Hope this informs. Kind regards,

Ihab

This video should be required viewing for all pilots!

In Barry Schiff's books/essays, he writes a lot about the skidding turn induced spin. It not only happens during the "impossible turn" scenario seen here, but also if you overshoot the base to final turn and try to cheat by adding more rudder. Definitely NOT the same stall we were all taught in primary training (in terms of warning signs, recovery, etc)

samiam wrote:In Barry Schiff's books/essays, he writes a lot about the skidding turn induced spin. It not only happens during the "impossible turn" scenario seen here, but also if you overshoot the base to final turn and try to cheat by adding more rudder. Definitely NOT the same stall we were all taught in primary training (in terms of warning signs, recovery, etc)

In the early days of aviation there were a good number of stall-spin accidents on the turn to final. Some aircraft were more susceptible that others, due to different airfoil characteristics. While we, the aviation community, are much more aware of the situation these days, the accidents continue to occur.

Some airplanes are way more forgiving than others in this scenario, but in all cases the situation is something to be avoided. Stalls close to the ground, even the good old stalls like we were taught in primary flight training, are not something to be trifled with. Keep the ball in the center an the plane won't spin! Always be aware of what's going on and keep flying the airplane.

Great video. But I've noticed that people always present this as if the rudder is a conscious, deliberate action. Even the instructor in this video says "add a boot-full of rudder" at one point.

A key thing to remember is that you may be adding rudder sub-consciously! The turn starts out fine, but as you progress your coordination deteriorates...

When coming in to land we all tend to get "target-focused" and try to make the sight-picture look right. The really dangerous moment is not the instance where you suddenly realize you're overshooting by a bunch (because then you're more likely to call it and go-around). Rather, the dangerous situation is the situation where you slightly overshoot and slowly squeeze in more rudder, and more rudder, and more rudder... until its too late and you don't even realize what you've done. Check yourself and put some conscious thought into not over-ruddering, in order to avoid falling into this trap.

In mentoring a bunch of glider pilots, I've seen a lot of then roll into a great 45-degree bank, but then struggle to hold attitude & coordination constant all the way around a circle. Its been proven to me through experience that everyone - EVERYONE - is naturally better at making coordinated turns in one direction or the other. It takes conscious effort and practice, to improve one's coordination in their "weak" direction. Luckily for glider pilots, we get good opportunities (i.e. thermals) to hold 45-degree banked turns and try to hold attitude & airspeed constant for several turns in a row. :D But flying behind a propeller, the opportunities are more limited.

Stay safe up there!

--Noel