Spin Entry Controls

[ahramin]

http://www.aceaerobaticschool.com/spins/

Admittedly my PPL spin training was a long time ago but I seem to remember for a left spin it would be full left rudder and full right aileron?

[Big Pistons Forever]

Out of spin aileron (ie right aileron in a left spin) will increase the speed of departure into the spin, spin rotation rate and may destabilize the spin. As a general rule it should never be used in general flight training and a major component of spin training should be to get students to resist the instinctive reaction to apply aileron opposite to the roll as the aircraft stalls.

The aerobatic certification for the C 150 Aeobat required only that the spin be tested to 6 turns. After that you are a test pilot. Anybody who spins a C 150 past 6 turns is being foolish in my opinion. The spin is a very dynamic maneuver and just because you had no problem recovering from a 10 turn spin yesterday doesn’t automatically mean you won’t have a problem today.

As a general comment the spin is an aerobatic maneuver and and should only be explored as a part of the foundation aerobatic skills provided in an introductory aerobatic course

At a regular flight school the emphasis should be focused on spin recognition and avoidance and the spin recovery should be initiated as soon as the aircraft departs from controlled flight and the aircraft should be recovered within one a maximum half turn. Pro spin controls should not be maintained in order to allow a full spin to develop as this is negative training.

[PilotDAR]

Pro spin controls should not be maintained in order to allow a full spin to develop as this is negative training.

Agreed. I've had a few types surprise me by needing an asserted recovery, where previous spins seemed comparatively benign. During demonstration of compliance for spin recovery, the standard requires the plane to be held in for one turn - no more, no less, and that's what I do. I believe that all pilots should be proficient at spin recognition, and recovery, but multi turn spins to not make this any better, they needlessly increase risk.

I also don't feel that there is any learning outcome benefit in aggravating the entry to a spin. Again, it creates a non useful representation of a spin and recovery. If you're going to demonstrate a spin, the entry should be steady and deliberate, with ailerons held neutral. If this is being done as dual training, and the candidate pilot has the knack of it with normal entries, the training objective has been achieved, on to the next lesson.

I was flying some flight testing on a modified Grand Caravan just before Christmas. I was asked by TC, in lieu of demonstrating spins (which demonstration I suggested against for the mod involved) to demonstrate mishandled stalls. To not have to deliberately spin, I agreed. The criteria was 75% power, 30 degree bank in each direction, and stall to the point of break, with one ball out. Interestingly, it required near full rudder to obtain the one ball out, so it was getting close to a spin entry anyway. The plane did drop a wing a few of the stalls, and I promptly recovered. TC was satisfied that I had demonstrated spin resistance during stall entry, so spin demonstration was not required. Note that these were flown with a G meter, as my previous experience spinning Caravans showed me that there can be quite a G and speed build up during the dive recovery.

Spin training has value, experimentation during training does not.

[EPR]

I was always taught..ailerons neutral prior to entering a spin. The C-150's were easy to spin, but the C-172's took a little persuasion to enter a spin cleanly...I remember right at the point of stall pulling back on whatever elevator control was left and bumping on, then off a few hundred RPM momentarily and over she goes. Recovery was about a wrist-ful of forward elevator and full opposite rudder to the direction of the spin.

[AirFrame]

I remember my instructor showing me spins to the left and when I asked about spins to the right was told "the 150 doesn't really spin to the right". I asked if I could try and he said "sure, go ahead". So right at the break I gave it full left aileron and the right wing dropped like a streamlined grand piano... We were a half-turn into the spin before my instructor said "I have control"... I was going to let it finish the full turn before recovering.

[lhalliday]

When I learned to fly in Cherokees the spin entry was a power-off stall, then full rudder and up elevator to initiate and maintain the spin. Some Cherokees spun well. Some refused and would only spiral. Straight down at red-line speed is not fun.

My Musketeer was originally certified for intentional spins, but this was rescinded in an AD (74-23-09). In addition to being slow to recover, a genuine spin (rather than a spiral) is apparently hard to achieve.

...laura

[paytoplay]

When I taught spins in the 172 our company used a power on stall technique with about 2000RPM and a nose high attitude .. Just as the stall horn started activating you would apply full back pressure on the elevator and full rudder deflection in the desired direction of rotation .. if you didn’t hold the control inputs in through atleast one full turn the aircraft would recover on its own with neutral controls and closing the throttle .. After 2-3 turns you needed opposite rudder and forward pressure etc to get out

[CpnCrunch]

I remember my instructor showing me spins to the left and when I asked about spins to the right was told "the 150 doesn't really spin to the right". I asked if I could try and he said "sure, go ahead". So right at the break I gave it full left aileron and the right wing dropped like a streamlined grand piano... We were a half-turn into the spin before my instructor said "I have control"... I was going to let it finish the full turn before recovering.

150 will spin fine to the left or right using just elevator and rudder input.

[AirFrame]

150 will spin fine to the left or right using just elevator and rudder input.

Maybe it was rigging, but this one wouldn't go to the right unless your foot was pushing the rudder pedal to the floor and the yoke pushing your navel into the baggage compartment. To the left, you could spin all day with a lot less effort.

[CpnCrunch]

Maybe it was rigging, but this one wouldn't go to the right unless your foot was pushing the rudder pedal to the floor and the yoke pushing your navel into the baggage compartment. To the left, you could spin all day with a lot less effort.

Was that power on or off? I did all my spins power off, but I imagine if you added power then that would use up some of your right rudder.

[PilotDAR]

I was required (by Transport Canada) to demonstrate 75% power spins in a Lake Amphibian while flight testing for a 210 HP Lycoming installation. Against the torque, it just hung there, and would not enter. With the torque, it just snap rolled, it never really dropped the nose. One power on snap roll (torque roll?) in a Lake Amphibian, and I declared that the spin testing was complete!

Yes, torque and rigging will affect spin entry - particularly on 150/152/172.

[AirFrame]

Was that power on or off? I did all my spins power off, but I imagine if you added power then that would use up some of your right rudder.

I don't recall now, but I suppose it's possible it was with power on. The only "spins" I really recall with power on were snap rolls (it was an Aerobat).

[PilotDAR]

Spins can be entered power on or power off. Both would have a slow approach to the stall, and then application of full rudder. A snap roll will have a very rapid application of stick back and rudder, from a faster entry speed. It'll involve G's, where a normal stall/spin should not involve G's during the entry. Note that the Cessna 152 flight manual says that a spin is a "slow deceleration" entry - so not a snap roll entry. The flight manual refers to both power off and partial power spin entries, but still "slow deceleration".

[Beefitarian]

Anecdote.

The only time I got a really great spin in a Cessna 172 was after I had been away for a while during my PPL training.

My instructor asked me to demonstrate a stall and recovery, then as I raised the nose without pulling the throttle to idle he commented, "Woo, he's going for one with power on."

As usual the left wing dipped and I did exactly what you tend to do as a student. Turned the funny half steering wheel to lift the wing which resulted in it instead violently dropping and around we went.

The instructor must have had confidence in my abilities to deal with the spin I created, since he was still heartily laughing well after I had recovered.

To be honest, it was a pretty good lesson. I got an excellent spin that was fully developed as well as a complete surprise which required me figuring out what was happening and how to recover. It just took a long time to understand it. A better debrief might have been good but we rarely did those back then. Probably my fault for saying no to being prompted, "Any questions?"

[CpnCrunch]

The 150 will drop a wing if the ball isn't perfectly centred when you do a stall...the 172 is a bit more forgiving.

[plausiblyannonymous]

I was always taught..ailerons neutral prior to entering a spin. The C-150's were easy to spin, but the C-172's took a little persuasion to enter a spin cleanly...I remember right at the point of stall pulling back on whatever elevator control was left and bumping on, then off a few hundred RPM momentarily and over she goes. Recovery was about a wrist-ful of forward elevator and full opposite rudder to the direction of the spin.

LOL a little persuasion.

For the 172S, I had to wait for the stall horn, then add full rudder, full aft control column, and jam the power forward for a second or two, all concurrently.

[PilotDAR]

jam the power forward

Easy on the throttle please. Spins can be flown throttle closed, and that's the better way to practice. There's no real benefit to aggravating things, it does nothing to improve the learning outcome.

172's with the camber lift wing (1974 and later) are a little less eager to drop a wing and enter a spin, as the improved airfoil is there to prevent spin entry. They'll do it, but more patience and a precise entry will result in a better spin. All 150/152's, and earlier 172's have the original airfoil, and spin more easily.