Yes, I agree, but the idea here is that we are looking for what properties have a positive effect on spin control. The airplane in his example was unnamed and maybe even a non-existant mathematical exercise. What relevant purpose does it serve to compare a fictional airplane with no known design factors presented, when searching for somethings that may prevent spinning? My comments are that a typical conventional airplane spins when it is moving too slowly to generate enough lift...usually when banked. I then explain that a design that continues to generate sufficient lift at whatever angle of bank (0-60) is the safer airplane. If that airplane can also make smaller turns (while banked or not banked), then that shows it is less prone to spinning. The videos obviously show that the STOL airplanes are less likely to spin.Billski's example was of a 42-knot stall airplane travelling at 50 knots. The Helio Courier's stall spped is 30 MPH, which is 26 knots. That makes a difference in turn radius. A big difference.
Any pilot knows that.
So going back to your statement
So it appears that an airplane with a slower stall speed is going to be less likely to spin, and since STOL airplanes usually generate the slowest stall speeds, they become one answer to building an airplane that is highly stall resistant."That makes a difference in turn radius. A big difference. Any pilot knows that"
Now I do not see how explaining a conventional airplane design with a higher stall speed which requires a huge turning radius particularly provides any useful data. The representation that because the imaginary airplane has a larger flat turn radius than it does a banked turn radius means that all airplanes will therefore do the same thing is not an accurate representation. There are lots of design factors, and every airplane will provide different results. I would think that an acrobatic airplane can reverse course in less room than it normally travels when doing a banked turn because it has features incorporated that allow extreme maneuvering.
We really seem to be going over the same territory and not covering anything new, and not having other inputs on something other than STOL airplanes.
The fact is that anything which allows you to maintain lift and control in any condition contributes to resisting spin at slow speeds. Obviously any maneuver which deviates from straight and level flight at slow speeds will increase the danger, even if its a routine maneuver. Different airplanes designs will result in differing risk levels in any maneuver. The aircraft which has higher landing speeds will by definition have more risk involved not only while landing but while making "routine" turns. The airplane that requires nearly 100 mph to land will normally require similar high speeds on the turn to final and be somewhat more difficult to make a banked turn and perfectly align with the center of the airfield. This type of airplane will probably have a higher risk factor for over banking and spinning than a slower and more docile aircraft.
Here is an automotive video on drifting. The thing I want you to watch for is the forward speed of the vehicle. As forward speed is allowed to
build the radius of the skidding turns becomes exponentially larger. When he slows the vehicle his turning radius becomes much smaller. The centrifugal forces have a large effect on both cars and airplanes, and this demonstrates that slower forward speeds enhance the ability for a smaller turning radius. Now, try to duplicate this same motion in the typical SUV (equivalent of a spam can). Not going to get the same result.