aerobatic newb impressions

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Monty

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Jul 15, 2010
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1,294
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Fayetteville, AR / USA
1. WOW!

2. FUN!

3. YOU SHOUD DO THIS!

4. a citabria is a pig in a roll.....unlike the RV.

5. really hard to overcome instincts to avoid spins. Once you do they are fun.

6. Loops and lazy 8's are my favorite.

7. accelerated stalls are ugly to the left with normal prop rotation.

8. I have a new "view" on the lengthy discussion about split S recovery from an unexpected roll inverted.
 

Monty

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Jul 15, 2010
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Fayetteville, AR / USA
Just rub it in. Na Na Na I got to do aerobatics Na Na Na. ;)
BJC wanted me to share how it went. I didn't think I should add any more fuel to the where's waldo thread. I am rubbing it in just a little though.....sorry.

Some of the uncoordinated control input exercises that my instructor gave me for homework would be easy for anybody to do for improved stick and rudder skills. I was doing them in my 172 flying back home.

1. look out at the wing tip and force it to describe a nice crisp squared off box. Do this while maintaining alt and heading. rotate one way and then the next at different speeds. Now do a circle. Switch wings and repeat. Do the same with the nose.

2. Place the nose on a point and roll side to side while keeping the nose firmly stuck on that point.

If you can do these things with precision without thinking......you are very good.

I can do it, sloppily, and not as consistent as I would like. I have a lot of room for improvement.

I think the chances of recovering from being flipped on my back with the flaps down at low altitude is almost zero. The amount of forward pressure required to keep the nose where you want it, even if you know what to do in the Citabria is surprising. This is with no flaps. With that much added camber, I don't think the added pitching moment is going to help that much. You might even run out of elevator. Rolling something that isn't good at it is work, a lot of work, and you are more likely to wind up in a vertical spiral. Not something I'm going to practice even at altitude, since the airframe isn't meant to do this kind of thing, and I'd probably rip the flaps off before I got it right, if getting it right is even possible.

I did identify a bad habit I developed of not giving enough right rudder in a climb. Not very noticeable in the 172, but very evident in the Citabria. I do get an extra 100 fpm or so of climb if I center the ball in the 172. So I came away from the whole thing with plenty of homework. I'm definitely going to go back for some more advanced work. All we had time for was the basics, and unusual attitude recovery. All the sailplane skills are still burned in the old noodle. Aero-tow really teaches you a lot about uncoordinated control inputs. And you can't turn those big wings without rudder, so my feet work. That is half the battle. I'm really grateful that I was able to learn that way, and had a great first instructor too.
 

TFF

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Apr 28, 2010
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Memphis, TN
Nobody has ever stopped rubbing it in on my account. More info the better; keep it coming.
 

Jay Kempf

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Apr 13, 2009
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Warren, VT USA
BJC wanted me to share how it went. I didn't think I should add any more fuel to the where's waldo thread. I am rubbing it in just a little though.....sorry.

Some of the uncoordinated control input exercises that my instructor gave me for homework would be easy for anybody to do for improved stick and rudder skills. I was doing them in my 172 flying back home.

1. look out at the wing tip and force it to describe a nice crisp squared off box. Do this while maintaining alt and heading. rotate one way and then the next at different speeds. Now do a circle. Switch wings and repeat. Do the same with the nose.

2. Place the nose on a point and roll side to side while keeping the nose firmly stuck on that point.

If you can do these things with precision without thinking......you are very good.

I can do it, sloppily, and not as consistent as I would like. I have a lot of room for improvement.

I think the chances of recovering from being flipped on my back with the flaps down at low altitude is almost zero. The amount of forward pressure required to keep the nose where you want it, even if you know what to do in the Citabria is surprising. This is with no flaps. With that much added camber, I don't think the added pitching moment is going to help that much. You might even run out of elevator. Rolling something that isn't good at it is work, a lot of work, and you are more likely to wind up in a vertical spiral. Not something I'm going to practice even at altitude, since the airframe isn't meant to do this kind of thing, and I'd probably rip the flaps off before I got it right, if getting it right is even possible.

I did identify a bad habit I developed of not giving enough right rudder in a climb. Not very noticeable in the 172, but very evident in the Citabria. I do get an extra 100 fpm or so of climb if I center the ball in the 172. So I came away from the whole thing with plenty of homework. I'm definitely going to go back for some more advanced work. All we had time for was the basics, and unusual attitude recovery. All the sailplane skills are still burned in the old noodle. Aero-tow really teaches you a lot about uncoordinated control inputs. And you can't turn those big wings without rudder, so my feet work. That is half the battle. I'm really grateful that I was able to learn that way, and had a great first instructor too.
Ahhh, the basics of control. I think all people that fly should do what you just did and they should go learn to fly a glider. A lot of power pilots get bad training. I have a corollary in the sports car world to your wingtip square. Basic shifting practice with rev matching. Stay at one speed and shift between gears using the throttle to hold speed. Do it fast and smooth until you can do it in any car with any gearing and you will be a much better driver and your clutch will last for 300k miles.

Sounds like a blast. Jealous.
 

BJC

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Thanks for sharing Monty.

I don't think of control inputs as "coordinated," only as what is needed to make the airplane do what you want it to. (I've heard "expert" CFI's discourage aerobatics because it "leads to uncordinated flight." Of course, they were intimitaded by the thought of stretching their necks.) Aerobatics is really all about making the airplane do exactly what you want it to, with precision, in three dimensions.

A C 172 with the wing unloaded will half roll OK, although I've never done it with the flaps down. At least now, your first reaction will be to push, not to pull into the ground if half-rolled by wake turbulence.

More advanced aerobatics = more fun, more satisfaction, and more likely to recover from an unusual attitude.


BJC
 

davidb

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Jun 3, 2008
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Vacaville, CA
I think the chances of recovering from being flipped on my back with the flaps down at low altitude is almost zero. The amount of forward pressure required to keep the nose where you want it, even if you know what to do in the Citabria is surprising. This is with no flaps. With that much added camber, I don't think the added pitching moment is going to help that much. You might even run out of elevator. Rolling something that isn't good at it is work, a lot of work, and you are more likely to wind up in a vertical spiral. Not something I'm going to practice even at altitude, since the airframe isn't meant to do this kind of thing, and I'd probably rip the flaps off before I got it right, if getting it right is even possible.
Monty, thanks for sharing and I look forward to more!

I'd say getting rolled over on final with flaps out from wake turbulence is something avoidable. I mean training emphasis for that scenario should be avoidance rather than recovery. Away from the pattern (with some altitude) is where upset recovery training could prove useful.

If you find yourself inverted, nose low and should be upright and level, I was taught to unload and roll. Unloading meant to push enough for zero Gs, not bothering with enough negative Gs to get the nose to track up while inverted. The idea was to stop the nose from burying at an accelerated rate while also increasing the role rate towards wings level upright. Once you get less than 90 degrees from upright, you start pulling positive Gs to get the nose back up to the horizon. Seems that is the quicker way (less altitude loss) to get where you want to be.

I've never done aerobatics in a prop plane so I'm curious to hear how torque and gyroscopic effects play into the whole thing.
 

BJC

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I was taught to unload and roll. Unloading meant to push enough for zero Gs, not bothering with enough negative Gs to get the nose to track up while inverted.
From nose down, inverted, you can't "push enough for zero g." You must push to get the nose up enough to then allow it to "float" back down at zero g to get maximum roll rate. If you are low, I recommend getting it above the horizon.

Most small propeller driven planes exhibit adverse yaw, which requires rudder into the roll (from inverted, opposite from the stick, another non-intuitive contol input) to get it started, and then opposite rudder to help keep the nose up. Torque makes the airplane roll opposite of propeller rotation. Gyroscopic forces come into play with yaw and or pitch changes. Neither are significant in a C172 or A152.

Pulling just past a vertical bank is a mistake.

All pilots should do what Monty did; get some training.


BJC
 

Monty

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Joined
Jul 15, 2010
Messages
1,294
Location
Fayetteville, AR / USA
Thanks for sharing Monty.

I don't think of control inputs as "coordinated," only as what is needed to make the airplane do what you want it to. (I've heard "expert" CFI's discourage aerobatics because it "leads to uncordinated flight." Of course, they were intimitaded by the thought of stretching their necks.) Aerobatics is really all about making the airplane do exactly what you want it to, with precision, in three dimensions.

A C 172 with the wing unloaded will half roll OK, although I've never done it with the flaps down. At least now, your first reaction will be to push, not to pull into the ground if half-rolled by wake turbulence.

More advanced aerobatics = more fun, more satisfaction, and more likely to recover from an unusual attitude.


BJC
I agree about just using the control inputs to make the plane do what you want. I went and flew the local Citabria for rent. Unfortunately you can't rent it without an instructor. But it was a gusty cross wind day and good for landing practice. On a left hand climb out, you need quite a bit of right rudder to stay "coordinated". I really have lost all interest in the 172.....
 
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