Slips and Skids

Be warned, this may over complicate things, but it works for me.

Imagine a race track that’s banked for a car going 100 mph. At 100 mph g-forces would be pushing the car straight onto the track. Fuzzy dice hanging from the mirror would hang straight down. The car’s rate of turn at 100 mph would be appropriate for the track’s banking.

Now slow to 80 mph. Suddenly the bank is too great for the rate of turn, the definition of a slip. If held to the same line, the fuzzy dice would move towards the inside of the turn. Which is what the ball does in a slip.

Now speed up to 120 mph. Now you’re going faster than the track designers figured, and your rate of turn is too great for the banking. Fuzzy dice will move towards the outside of the turn, like the ball does in a skid.

As an aside, I had a piece of yarn attached to the canopy of my Sky Arrow for a while as a slip/skid indicator. First time I slipped or skidded, it moved opposite to what I had imagined. It makes sense now, but like the ball for you it seemed backwards at first.

You can see in this video the yarn moves exactly opposite the ball when slipping back and forth across the runway.


Yeah. It took me awhile to get it through my head to 'step on the knot,' not the end of the string
 
A slip can be a good collision avoidance tool. Gets the cowl out of the way so you can see what's in front of you . I plan my descents later than typical knowing I will be deliberately be doing slips just for that. I will do it on climbs also.
 
I don’t think I’ve ever heard that interpretation before, nor do I recall reading it anywhere.

Is that original? Just curious. If that visualization works for someone, go for it!

Thanks. I've been using it for a long time and yes, it's original.

 
Is Paul Simon a pilot?

Slip slidin' away
Slip slidin' away
You know the nearer your destination
The more you're slip slidin' away
 
That sounds backwards to me.
It is backward. Front tires skidding is understeer, also know as a push. If you've experienced this, you'd know why. It literally feels like the car is pushing the front tires rather than turning.
Oversteer is the rear wheels skidding. Often called loose as your rear end is loose (making the understeer tight).

It matters not which are the driven wheels. It has to do with which are the STEERING wheels.
 
Wonder why then in a side slip or forward slip, tail kicks out... so wouldn't that be a skid? Not trying to confuse people, but it is a little odd to me. Like a side slip in a crosswind you bank in the direction of the wind, then use opposite rudder to maintain centerline. But the tail is moving opposite the direction of the bank... so a skid?? Now I'm confusing myself.
 
Simplified: if you have too much bank for your rate of turn, you have a slip.

By implication, any time you have bank with NO rate of turn, you’re slipping.

This “Where is the tail?” seems to clarify it for some, but for me it just doesn’t help.
 
Wonder why then in a side slip or forward slip, tail kicks out... so wouldn't that be a skid? Not trying to confuse people, but it is a little odd to me. Like a side slip in a crosswind you bank in the direction of the wind, then use opposite rudder to maintain centerline. But the tail is moving opposite the direction of the bank... so a skid?? Now I'm confusing myself.

Is this guy skidding or slipping? Left rudder, right aileron. Sounds like a slip. But if you look at it from above will he appear to be 'skidding' around the corner?

https://www.pilotsofamerica.com/community/threads/low-alt-cross-controlled-turns.115797/
 
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Wonder why then in a side slip or forward slip, tail kicks out... so wouldn't that be a skid? Not trying to confuse people, but it is a little odd to me. Like a side slip in a crosswind you bank in the direction of the wind, then use opposite rudder to maintain centerline. But the tail is moving opposite the direction of the bank... so a skid?? Now I'm confusing myself.

I was wondering, and thinking about asking the exact same thing. Then (not sure if this is THE answer) I thought “difference is in a side slip or forward slip, we are not trying to turn!”

seems like the skid part is because the flight path is curved and it is not line with it.
In forward slip you are flying straight, just with the plane at an angle. Which doesn’t cover for example the low wing with the nose, etc.
also in a side slip for landing you are slipping, but again nut turning, just using rudder to actually keep straight aligned.

that’s all I got.
 
Wonder why then in a side slip or forward slip, tail kicks out... so wouldn't that be a skid? Not trying to confuse people, but it is a little odd to me. Like a side slip in a crosswind you bank in the direction of the wind, then use opposite rudder to maintain centerline. But the tail is moving opposite the direction of the bank... so a skid?? Now I'm confusing myself.

How about this. The tail kicks 'out'. It kicks out to the side of the flight path. If it kicks out to the outside of the turn, it's a skid. If it kicks out to the inside of the turn, it's a slip.
 
Hello there!

I am doing some research for a paper, and I am doing research to further understand slips and skids. What makes them specifically different, and why if allowed does the stall occur the way it does in each situation. I think this is something that a lot of students don't ever really grasp in depth.
In a skidding turn, the low wing will stall first and throw you into a spin; in a slipping turn, the high wing will stall first, and return you more-or-less to level flight.

I use slipping turns on a lot when I have to lose altitude in a tight turn from downwind to final (e.g. fitting in between jet arrivals at a busy airport). I have never deliberately done a skidding turn, at any altitude.
 
How about this. The tail kicks 'out'. It kicks out to the side of the flight path. If it kicks out to the outside of the turn, it's a skid. If it kicks out to the inside of the turn, it's a slip.
And if you're not turning? Most of us refer to that as a slip as well.

At least nobody brought up the inane FAA definition of uncontrolled flight, though they come close with the "not enough/too much" bank angle for rate of turn.

Uncoordinated flight is simple. The airplane is not aligned with the relative wind (in yaw). This is easy to visualize in a glider or something else without a big fan up front when you have a string that points back at you that lets you see if you're so aligned.
 
Simplified: if you have too much bank for your rate of turn, you have a slip.

By implication, any time you have bank with NO rate of turn, you’re slipping.

I think this makes sense, then, to describe both a slipping turn (bank with not ENOUGH rudder) and aileron deflection with so much rudder there is no turn (side slip). In my mind it makes sense now... I think...
 
The one where it shows the four forces of flight in balance (where one is centrifugal force) and tries to explain coordination in terms of that.
 
The one where it shows the four forces of flight in balance (where one is centrifugal force) and tries to explain coordination in terms of that.

Oh, that.

19220_3.jpg
 
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