Slip/Skid no Spin

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Can a spin be entered from a slip? Why or why not?
Can a spin be entered from a skid? Why or why not?
 

screennamie

New Member
I don't see why not. So long as the aircraft is in a stalled state and you remain uncoordinated either way. I guess it would be in stages: cross control stall/slip, then spin or accelerated stall/skid, then spin.

It would also depend on the weight, loading and aircrafts stalling characteristics, dihedral, hershey bar wing vs tappered or eliptical. Engine mounting, torque, pfactor, power settings.

But the stall has to happen first no matter what. Maybe someone else can elaborate
 

USMC-SSGT

Well-Known Member
Yes and its actually pretty fun to try (with someone experienced.) When I used to teach unusual attitudes or do spin training these were two of the 4 I would teach. 1 was a spin from a skidding turn and the other was a spin from a slipping turn.

To set up the slipping turn it was basically enter a steep turn to the left while bleeding off airspeed and apply a healthy dose of right rudder. The stall would break and your right wing would drop and the airplane would spin to the right. We also called it an over the top spin because if you picture that "top" or right wing stalling first in a left hand turn that wing would have to drop and begin to spin which would in turn send the left wing over in almost a 180 degree arc sending you partially inverted for a moment.

To set up the skidding turn it was basically enter a steep turn to the left (or right) and apply a healthy dose of left rudder. The inside or left wing would stall first and it would be your classic turn to base style spin.

Slipping or skidding does not matter in a spin, if you are uncoordinated in a stall one of your wings will stall first causing the spin.
 

nosehair

Well-Known Member
The stall would break and your right wing would drop and the airplane would spin to the right.
...in that moment, when the right wing drops,...the nose begins to yaw to the right, reversing the slip to the left to a yaw to the right.

...if, at that moment, you have enough rudder authority to stop the yawing moment to the right, you would prevent the spin.

...you might say you wouldn't have enough rudder authority to stop it, and you may be right; depends on the airplane and such.

...but if you go sharp forward elevator at the same moment as the right wing drops to get more rudder authority to prevent the yaw, the spin will not develop.

...so I say, it does matter that you know the difference between slip and skid.

...you are probably right that it does not matter to the untrained pilot. A precisely controlled slip is a beautiful thing - not scary at all, if properly done. There will be no wallowing of the nose, or wallowing of the bank, or wobbling of the flight path. There is a smooooth slide sorta sideways down to the runway. No yawing of the nose, except as needed and intended.

...it is precisely the nose yawing action that causes the asymetrical lift that starts the whole process.
 

Blackhawk

Well-Known Member
Can a spin be entered from a slip? Why or why not?
Can a spin be entered from a skid? Why or why not?
#1 depends on the airplane, but slips are generally more spin resistant than skids. Many high wing airplanes will not spin from a slip. In my Decathlon, for example, when I try to spin from a slip, it just bobs up and down. This seems to be because as the airflow seperates from the wing root, it does so at an angle that it hits the horizontal stabilizer, which pitches the nose down, causing the airflow to reattach, which causes the nose then to pitch up into another stall, etc. etc. The whole time, the ailerons and the rudder remain effective enough (probably in attached flow) to sustain the slip on your track. I've also tried this in a C-140, and I could not get it to spin from a slip. I've intended to try it in a C-152 and C-172, but have not had the time. Again, I'm not saying ALL aircraft won't spin from a slip. (Extras, for example, will).
As for #2... you're kidding, right?
 

mjg407

Well-Known Member
In primary flight training you do a demo in the T-34C, the skidded turn stall. Plane inverts rapidly, and you enter an inverted spin.
 
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