is this device widely known about ?

[fairchild1934]

https://www.youtube.com/watch?v=kj7ZsnHrD-c

Leading edge wedges that allow the plane to all most auto-recover from spins...... ( or not spin at all--- maybe--- if moved inboard. )

I found it an interesting video.

Tim

[Redneckmech]

Interesting, It looks much like the stall strip used on the inboard right wing of the F4U Corsair, or a larger version of the stall strips used on both inboard and outboard leading edges of the Piper Tomahawk. They are use to trip the boundary layer to turbulent in specific locations to either in the case of the F4U make both wings stall at the same airspeed, and in the case of the tomahawk to provide a consistent stall due to the flex within the wing.

Edit: Boldmethod has a nice article on it, https://www.boldmethod.com/learn-to-...aft-explained/