Spin recovery

In aircraft with the propeller rotation clockwise, (as viewed from the rear) the gyroscopic forces from the prop only permit flat spinning to the left while upright, or to the right inverted. Forgive the generalities, I'm speaking of the Pitts Special, the only machine I have (flat) spun. Never tried it opposite, but the spinning prop would tend to lower the pitch attitude, would it not?, thereby preventing the spin from going flat. Obviously, your milage may vary.
 
j1b3h0 said:
In aircraft with the propeller rotation clockwise, (as viewed from the rear) the gyroscopic forces from the prop only permit flat spinning to the left while upright, or to the right inverted. Forgive the generalities, I'm speaking of the Pitts Special, the only machine I have (flat) spun. Never tried it opposite, but the spinning prop would tend to lower the pitch attitude, would it not?, thereby preventing the spin from going flat. Obviously, your milage may vary.
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I have never seen an airplane with a clockwise-turning propellor (Lycoming) do a flat spin to the right as seen from the ground. In my experience, adding power in a right rudder upright spin pulls the nose down due to gyroscopics. The airshow type of flat spin, which is a gyroscopically-driven maneuver will always be done with left rudder upright and right rudder inverted. In both cases, rotation is to the left as viewed from the ground. CCW-turning engines (Russian radials) are the opposite. That being said, there ARE some airplanes that will spin flat in either direction, but it is not because of propellor gyroscopics, but rather an aerodynamic quality that causes the spin to go flat without the addition of power. I don't care for that in an airplane. This will not happen to most aerobatic airplanes due to their neutral aerodynamic qualities, and effective control surfaces.
 
RoscoeT said:
I have never seen an airplane with a clockwise-turning propellor (Lycoming) do a flat spin to the right as seen from the ground. In my experience, adding power in a right rudder upright spin pulls the nose down due to gyroscopics. The airshow type of flat spin, which is a gyroscopically-driven maneuver will always be done with left rudder upright and right rudder inverted. In both cases, rotation is to the left as viewed from the ground. CCW-turning engines (Russian radials) are the opposite. That being said, there ARE some airplanes that will spin flat in either direction, but it is not because of propellor gyroscopics, but rather an aerodynamic quality that causes the spin to go flat without the addition of power. I don't care for that in an airplane. This will not happen to most aerobatic airplanes due to their neutral aerodynamic qualities, and effective control surfaces.
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IIRC, adding power will reduce the pitch attitude when spinning in either direction in most airplane, it's just more effective when the gyroscopic precession of the prop helps rather than hinders the reduction in pitch attitude and/or increase in rotation rate. I also seem to remember that aileron deflection in one direction flattens the spin but I can't for the life of me remember whether that's true for pro spin aileron (aileron away from the low wing or the other way.
 
gismo said:
IIRC, adding power will reduce the pitch attitude when spinning in either direction in most airplane, it's just more effective when the gyroscopic precession of the prop helps rather than hinders the reduction in pitch attitude and/or increase in rotation rate. I also seem to remember that aileron deflection in one direction flattens the spin but I can't for the life of me remember whether that's true for pro spin aileron (aileron away from the low wing or the other way.
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Other way. Trying to "Fix" the spin by picking up the wing accelerates the spin - you effectively increase the angle of attack of the wing that is furthest on the back side of the lift curve. My brother shows that in his video that I posted somewhere in this thread.
 
Capt. Geoffrey Thorpe said:
Other way. Trying to "Fix" the spin by picking up the wing accelerates the spin - you effectively increase the angle of attack of the wing that is furthest on the back side of the lift curve. My brother shows that in his video that I posted somewhere in this thread.
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That's what I mean by "Pro-spin" aileron so maybe I'm remembering correctly. By "accelerates" do you mean the spin gets flatter or more nose down as the rotation rate increases?
 
gismo said:
That's what I mean by "Pro-spin" aileron so maybe I'm remembering correctly. By "accelerates" do you mean the spin gets flatter or more nose down as the rotation rate increases?
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OK.

Upright spin to the left, stick to the right, nose comes up.
 
Capt. Geoffrey Thorpe said:
OK.

Upright spin to the left, stick to the right, nose comes up.
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Yup, that's exactly what I meant. To me pro spin aileron means putting trying to raise the lower wing in an upright spin. It's "pro" spin because the down aileron increases the drag on that wing and adds to the effect of the rudder deflection in the direction of yawing.
 
Extracts from some magazine articles as discussion points:

1. Sport Aerobatics Magazine December 1986 Spinoffs Part 3 by Gene Beggs.
"Incidentally, you should remember that when performing either upright or inverted flat spins in the Pitts and Eaglle aircraft using full power, you must be spinning AGAINST the engine rotation in order for the gyroscopic forces produced by the engine and propeller combination to be able to raise the nose. To further simplify that statement, you could say that you can only do an INVERTED flat spin in these two aircraft with RIGHT RUDDER and you can do an upright flat spin only with LEFT RUDDER! It simply won't work the other way around!"

2. Sport Aerobatics Magazine April 1994 Spinning With Gene Beggs The End
" The following is an outline of the spin training program that I use in checking a pilot out in a Pitts type aircraft.
...
(II) Cross Controlled or Flat Spins. (Upright and inverted, left and right, power off, stick either full forward or full back, full opposite aileron)
..."

3. Sport Aerobatics Magazine October 1985 Spinoffs Part 2 by Gene Beggs.
"...Cessna 150. I found that in spins both to the right and left, the use of full opposite aileron (outspin aileron), would always produce a recovery from the spin! This is completely backwards to the results obtained in all other aircraft...."

4. From Sport Aerobatics Magazine of May, 2005 - The Spin that Spooked by Dave Monds - in a Pitts S-2B
"ie: upright can only flatten to the left and inverted can only flatten to the right.
...
I wanted to test this principle after hearing comment that flat spins were actually possible in the other direction.
Only one other factor, aside from a significantly aft centre of gravity would enable the spin to flatten, aileron.
.....
Feeling comfortable with the right hand spin I planned to introduce power and aileron to the next spin to try and get it to flatten.
The entry was normal and I began increasing power after a rotation. There was a slight flattening which I can’t explain but otherwise the spin was still rolling and steep.
.....
I then applied full left aileron, with the stick still fully aft and noticed a significant flattening of the spin. Satisfied that the spin was flat but not nearly as much as in the left hand direction with power assisting. I put the stick fully forward and left to accelerate.
......
What happened next was breathtaking. The spin wrapped up tightly and the rotation went ballistic.
Having experienced all manner of spins and snaps previously the rate of rotation here was beyond anything I had seen.
Nothing outside the aircraft was discernable except what was above and below the horizon, ground and sky.
I noticed the feeling of being a long way from the controls as I was pushed against the left cockpit wall. In reality I hadn’t moved an inch, my harness would see to that, but the extreme sideways force can create this illusion."
 
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