What factors contribute to wing drop?

SixPapaCharlie

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Got checked out in a 2000 172SP yesterday.

Doing both power off and power on stalls, I couldn't have had that ball more centered if it was sitting on the ground.

In each case that thing wound itself over the right wing as it pitched down.
Has to be pilot and not plane because my bird does this every time too. Always to the right.

In the first 172 I trained in, we would just get a little settling of the nose and that was it.

Only difference was in that original 172, we never pitched up as steeply for stalls as I have in planes with subsequent instructors.

I am told the wing won't drop if you are coordinated. I suspect there are other things at play. :dunno:
 
Another interesting thing I noticed yesterday is the airspeed was dead long before the stall. I suspect this has to do with pitot angle relative to the wind. Stall speed was supposed to be 48 but ASI indicated zero 4-5 seconds before the fun started.
 
I generally would get a wing drop at stall on the SPs I have flown. My old instructor would have me do slow flight with IAS on G1000 at 0.. couldn't do it very long as it required full or almost full power. Was fun but right leg sure got tired.. haven't flown since Feb 2014 :redface:
 
Power on stalls do not have to be performed at full power. Try with about 80 percent throttle. Another factor might be your high pitch attitude due to the HP of the SP.

My guess is 80% throttle and a lower pitch will mellow the wing dropping tendency.




-bulldog
 
Power on stalls do not have to be performed at full power. Try with about 80 percent throttle. Another factor might be your high pitch attitude due to the HP of the SP.

My guess is 80% throttle and a lower pitch will mellow the wing dropping tendency.




-bulldog


I am getting the drop on power off too.
 
If you are getting right wing drop you are over compensating on the rudder, natural tendencies will be left unless you have an oddball engine that turns the other way. If it was a one plane thing I'd suspect rigging, but like you, with more planes the focus turns to the pilot. How much parallax do you have with the ball appearing centered?
 
How much parallax do you have with the ball appearing centered?


I'd say very little given the Turn coordinator location.
Here is the panel

IMG_0987.JPG
 
I'd say very little given the Turn coordinator location.
Here is the panel

IMG_0987.JPG

Well, you get some. Why don't you experiment relaxing the rudder and seeing where the ball needs to be to break straight, and then transfer that into another plane? Also, are you staying with the ball until the break, or are you looking out the window subconsciously adding more rudder in anticipation?:dunno:
 
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I am starting to think I need to step on the left rudder as it breaks.
Naturally during stall practice, I am going to have right rudder in for maintaining coordination. I wonder if I am waiting too long to start correcting.
 
I am starting to think I need to step on the left rudder as it breaks.
Naturally during stall practice, I am going to have right rudder in for maintaining coordination. I wonder if I am waiting too long to start correcting.

As it starts breaking it sounds like you must be increasing right rudder. I've never had to add left, but I ease right as it starts to break.
 
As it starts breaking it sounds like you must be increasing right rudder. I've never had to add left, but I ease right as it starts to break.
This was always the case for me in the 150. I couldn't let out of right rudder fast enough to keep the nose from going right.
 
Start with power off stalls. Cover the turn co-coordinator with a partial panel training device (see your CFI). As you increase the pitch towards the stall with the wings level pin the nose on a cloud and ruthlessly stop ANY yaw with your feet. If the wings are level and the is no yaw there will be no wing drop unless the a/c is out of rig. For power on stalls do the same. Start at 1500 rpm then 1800, 2100, and so on. If you stop the yaw you will break straight ahead. For turning stalls have your CFI show you how to make coordinated turns without the turn co-ordinator.... Good Luck.
 
Got checked out in a 2000 172SP yesterday.

Doing both power off and power on stalls, I couldn't have had that ball more centered if it was sitting on the ground.

In each case that thing wound itself over the right wing as it pitched down.
Has to be pilot and not plane because my bird does this every time too. Always to the right.

In the first 172 I trained in, we would just get a little settling of the nose and that was it.

Only difference was in that original 172, we never pitched up as steeply for stalls as I have in planes with subsequent instructors.

I am told the wing won't drop if you are coordinated. I suspect there are other things at play. :dunno:

A cross wind will kick a wing up, lowering the opposite wing. When you nose over after the stall, note if a cross wind exists and press the rudder a little into it as you go over the hump.
 
A cross wind will kick a wing up, lowering the opposite wing. When you nose over after the stall, note if a cross wind exists and press the rudder a little into it as you go over the hump.

Bullhockey. Where do you get these goofy ideas of aerodynamics from?
 
A cross wind will kick a wing up, lowering the opposite wing. When you nose over after the stall, note if a cross wind exists and press the rudder a little into it as you go over the hump.

Only if your airplane is a kite.

Once airborne, the ground is irrelevant for anything but navigation.
 
Bullhockey. Where do you get these goofy ideas of aerodynamics from?

From experience. Whats you problem? You don't fly anymore? Or do you stay out of the wind?
 
. As you increase the pitch towards the stall with the wings level pin the nose on a cloud and ruthlessly stop ANY yaw with your feet. If the wings are level and the is no yaw there will be no wing drop unless the a/c is out of rig.

This-

If you reeely focus on keeping the nose absolutely straight, with the rudder, and the wings absolutely level, the ball will NOT be exactly centered.
Due to the assymetrical thrust of P-Factor during the nose-high attitude.

This is not so noticible in light powered airplanes, but becomes obvious in higher powered airplanes and if you watch your heading indicator for rudder control, and attitude indicator for wings level, you will see the ball slide slightly to the right. Your attempt to center the ball pushes the nose slightly right during the stall with the subsequent right wing drop.

Yes, assymetrical thrust from the P-Factor .
 
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A cross wind will kick a wing up, lowering the opposite wing. When you nose over after the stall, note if a cross wind exists and press the rudder a little into it as you go over the hump.

Huh????
 
Try the "falling leaf". Hold it in the stall and keep the nose on a point on the horizon with the rudder pedals.
 
A cross wind will kick a wing up, lowering the opposite wing...

So following that logic, if there were a "headwind" you wouldn't be able to stall at all. :rolleyes:

Seriously though, in an abrupt stall this is a trait that some airplanes exhibit. Does it mean it's out of rig? Not necessarily, airframes are far from perfect and there are all sorts of offsets and tweaks to compensate for the various impure aerodynamic forces acting on them. They are not rigged to drop out of a deep stall with level wings, they are rigged to fly as straight and true as possible in cruise configuration. This may come with some compromises but with enough time and practice to learn the individual nuances of this particular aircraft you should be able to do the stalls with virtually no drama whatsoever.

What I mean is, I wouldn't worry about it. You certainly don't own the only 172SP that does this.
 
What I mean is, I wouldn't worry about it. You certainly don't own the only 172SP that does this.

No I am not worried about it from that perspective. I have a different plane that has this same behavior.

Going up in this 172 and seeing this same behavior makes me believe I am doing something incorrect.

I think I am waiting until the stall is too fully formed to react.
 
...makes me believe I am doing something incorrect...

I'd say that "incorrect" might be a bit too harsh of a term for what you are doing. First of all the airplane is not supposed to be in this realm and although they may have gone to great lengths to mitigate the drama of the stall event the aircraft's behavior in that zone was certainly not the prime focus of the designers when they built it. What you are doing is taking it beyond the edge of it's operational envelope and as you approach the stall the positions of the flight controls that might be required are way outside of what you'd probably consider normal. So you might be hesitant to apply them but, like I said, the designers did go to lengths to ensure that the transition and recovery from that event would be benign and despite the drama you might feel when the wing drops you are okay.

I think if you wanted to you could go up and spend an hour doing nothing but stalls and you'd most likely get a real handle on it and probably, without even really thinking about it, your basic motor functions would learn how to minimalism, if not completely eliminate what concerns you.

I can tell you one thing for sure, you're not gonna figure it out here.
 
I think incorrect is a quite an appropriate word. Non judgemental, just stating it isn't quite right, he also has a handle on what and why now, he can correct it.
 
Yes, assymetrical thrust from the P-Factor .

Agree, very high angle of attack at high power == high P factor. When it breaks and you nose over, P-factor largely goes away, and the right wing drops.
 
From experience. Whats you problem? You don't fly anymore? Or do you stay out of the wind?
Apparently I fly in the wind more than you do. And I have a better understanding of aerodynamics. A steady wind has no bearing to the airplane in the air. The airplane can't tell. The crosswind is not going to "pick up a wing" or anything else.
 
I'll just join the chorus. Logical explanation is that you're not relaxing the right rudder after the stall breaks. Flip side is that means you're doing a nice job of keeping it coordinated right up to the break. :D

I know that because if I drop a wing in a power on stall in the 172 it's always the left because I don't have quite enough right rudder in before the stall.
 
Perhaps the best way to get the skill is to do a lot of MCA practice. Flying along with the stall horn blaring and keeping coordinated will help you develop an innate ability to keep the ball centered.
 
Agree, very high angle of attack at high power == high P factor. When it breaks and you nose over, P-factor largely goes away, and the right wing drops.

That makes all kinds of sense for a power-on stall, but I don't understand how it's a factor at idle power. P-factor should be negligible if the engine is throttled.

Now, I'm certain I'm missing something, as there sure seems to be very noticeable left turning tendency in a 182 during flare. Maybe gyroscopic effect? The engine may not be producing that much thrust, but it's still spinning at almost half speed.
 
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Elaborate

Don't have time to elaborate right now, but - Lateral CG.

Simply put my 170lbs and my instructors 260lbs = half ball out to get rid of the feeling in your butt. I guarantee that if you fly with a lateral cg like that with the ball in the box you will have a half a sore lower back by the end of the day. :yesnod:
 
There is also a ground adjustable rudder trim tab on the SP. I think ours might be a wee bit off, but not enough to muck with it.
 
A cross wind will kick a wing up, lowering the opposite wing. When you nose over after the stall, note if a cross wind exists and press the rudder a little into it as you go over the hump.

Another CTLSi gem. I can't figure out if you actually mean the things you say, or if you are a very clever troll.
 
OP, try not focusing on the ball, but rather feeling like your ass is centered in the seat with ZERO sideways pressure and use the rudder as required to stay feeling centered right up to the stall. Gets you more in tune with the airplane rather than staring at and chasing some instrument on the panel. Just experiment with rudder usage. Do what it takes. Look out the windshield. Keep the heading locked on a point. Feel what the airplane is telling you, and is about to do. Use that rudder as required as the nose is dropping to keep the wings level. Might take a quick jab of full rudder and back to center the instant the stall breaks, if you see roll starting to happen. Unless the airplane is way out of rig, wing drop can be controlled.
 
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A cross wind will kick a wing up, lowering the opposite wing. When you nose over after the stall, note if a cross wind exists and press the rudder a little into it as you go over the hump.

Your plane flies and stalls in the relative wind which is on your nose. Your correction is for a wind that exists only in your imagination.

Ever swim across a river?
 
I am told the wing won't drop if you are coordinated. I suspect there are other things at play. :dunno:

This is more or less true.

Henning was on the money, if the right wing is dropping during a power ON stall, its only doing this because you are giving it too much right rudder. A 172 in a power-on stall will break hard left if you don't use right rudder to keep the plane coordinated.

You don't need to be staring at the ball the whole time, just know that if you go into a stall reasonably coordinated (good deal of right rudder for a power on) you won't get a bad wing drop.
 
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