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Elevators not lined up.


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My 1965 M20E elevators do not line up at all. I had a heavy wing and that was fixed with one turn of the flap stop bolt. Also my rudder trim tab is fully deflected to the copilot side. In my quest to make sure the plane is straight and true, I’ve noticed these elevators. Does anyone have a connection to rigging boards? My plane is going back into the shop next week for a single piece windshield and electric step conversion in the KC area. It’d be really nice to get her rigged too. Thanks

 

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Just now, Prior owner said:

I agree….and unfortunately I’ve seen quite a few like that. I don’t understand why anyone would want to mess with the elevators like that.

I don’t either, but there are more landing gear screwed by people trying to “fix” it then controls. If it ain’t broke, don’t fix it. 
 

we can’t change the past, we can only try to do our best. You can even them up, but which one is right? It will take a full rigging according to the manual to get it right. 

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6 hours ago, Prior owner said:

I agree….and unfortunately I’ve seen quite a few like that. I don’t understand why anyone would want to mess with the elevators like that.

It’s been painted so elevators and other controls are removed to be painted and rebalanced. If painted recently I would take it back to the shop to have it adjusted.

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2 hours ago, ArtVandelay said:

It’s been painted so elevators and other controls are removed to be painted and rebalanced. If painted recently I would take it back to the shop to have it adjusted.

It was painted about three years ago in Tampa but the previous owner was an A&P. I'm kind of blown away that he wouldn't have noticed that. 

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1 hour ago, gmonnig said:

It was painted about three years ago in Tampa but the previous owner was an A&P. I'm kind of blown away that he wouldn't have noticed that. 

You may be surprised at what people don’t notice, for instance I assume whoever adjusted the flap to correct for a heavy wing didn’t notice the elevator mis match.

Not on a Mooney but I’ve not had good luck adjusting a flap for a heavy wing, it seems that the adjustment has more effect with flaps down than up.

People will do strange things on occasion, it may be that the elevators were that way trying to correct for a heavy wing, or simply a mistake.

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With the rudder trim tab fully deflected, elevators misaligned (never anywhere mentioned as a correction for a heavy wing) and a flap being adjusted, you need to go to a shop that has the proper travel boards and can follow all the directions in the manual to align the control surfaces. After that, small corrections may need to be made.

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5 hours ago, Airways said:

Following…

 

I have a heavy left wing that doesn’t get resolved with the aileron tab bending.

Aileron trim tab?  Mooney didn't install trim tabs.  The only approved ones are made by Aero Trim and they're adjustable.  You need to get to a shop with a set of travel boards to get the rigging correctly adjusted.

Clarence

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I read that to mean bending the trailing edge of the aileron.

Buy you never know, when I bought my Maule and it had an aileron trim tab on it.

However as a dual strut braced wing you adjust the length of one of the aft struts to warp the wing to adjust for wing heaviness, they aren’t supposed to have a trim tab.

Someone I’m sure just put an aileron trim tab on it, because you know, Cessna’s have them. I removed it of course and lengthened the strut on the wing light side.

People won’t read the book sometimes and whoever put the trim tab on the Maule obviously had no old aircraft design experience

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2 hours ago, A64Pilot said:

I read that to mean bending the trailing edge of the aileron.

Buy you never know, when I bought my Maule and it had an aileron trim tab on it.

However as a dual strut braced wing you adjust the length of one of the aft struts to warp the wing to adjust for wing heaviness, they aren’t supposed to have a trim tab.

Someone I’m sure just put an aileron trim tab on it, because you know, Cessna’s have them. I removed it of course and lengthened the strut on the wing light side.

People won’t read the book sometimes and whoever put the trim tab on the Maule obviously had no old aircraft design experience

Sometimes owners don't want to pay maintainers to read the manual and process, so they do what they want.  The wrench swings both directions.

Clarence 

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4 hours ago, M20Doc said:

Aileron trim tab?  Mooney didn't install trim tabs.  The only approved ones are made by Aero Trim and they're adjustable.  You need to get to a shop with a set of travel boards to get the rigging correctly adjusted.

Clarence

I agree. Do all Mooney service Centers have the boards? 

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22 minutes ago, Shadrach said:

Mine are not exactly even and I’m 90% sure it has never had any adjustments made to the elevators.

Ok, on further thought on that, the rigging specs have a lot of leeway. It is possible that the OPs elevators meet specs. One could be at the neg limit and the other at the positive limit. After all, you can only adjust them by 1/2 turns of the rod end. 

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22 minutes ago, N201MKTurbo said:

Ok, on further thought on that, the rigging specs have a lot of leeway. It is possible that the OPs elevators meet specs. One could be at the neg limit and the other at the positive limit. After all, you can only adjust them by 1/2 turns of the rod end. 

So the question is could I gain a knot or two with careful rigging? My bird is upper end of speed for an M20F (150+KTAS) but one of the aileron horns protrudes ever so slightly above the wing tip in level flight and the elevators are not precisely matched.

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5 minutes ago, Shadrach said:

So the question is could I gain a knot or two with careful rigging? My bird is upper end of speed for an M20F (150+KTAS) but one of the aileron horns protrudes ever so slightly above the wing tip in level flight and the elevators are not precisely matched.

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There was a thread about this several years ago, and many of us posted photos. Most of us had elevators slightly down as you show here. But considering how the empennage trims, along with variations in weight, CG, altitude, air pressure, TAS and headwind / crosswind / tailwind variation, I expect elevator-to-horizontal stabilizer position to not be the same. You van play with it and make itlkine up for your common flight conditions, but will you choose full tanks or half, forward or rear CG?

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14 hours ago, Shadrach said:

So the question is could I gain a knot or two with careful rigging? My bird is upper end of speed for an M20F (150+KTAS) but one of the aileron horns protrudes ever so slightly above the wing tip in level flight and the elevators are not precisely matched.

D169CA88-029A-413C-8B7A-5A6290FDB0EA.jpeg.6d64ab968b003ab1dcb621bb8383fe1a.jpeg754F3B1A-846B-4897-8B45-4E66E2B9C822.jpeg.001fd5048596aba5044eaf9a243c3a97.jpeg

 

If say for example the elevators are mismatched it will create drag as one will be up a little and one down a little to cancel each other out.

Is it enough to measure? I don’t know, depends on how bad it is.

Playing with rigging on a crop duster I learned with the ailerons both slightly up it was slightly faster, roll rate increased and control forces were lighter, and by being slightly up, you slightly washed out the wing making it less likely to tip stall.

It also may have made it so it took slightly longer ground runs and slightly increased stall speed, but I didn’t measure either.

Many will argue rigging won’t make much if any difference as the flight controls will be positioned where they need to be, but experience has shown otherwise.

What got me started on aileron rigging was some were drooping them in an attempt to carry more weight, they were also changing the angle of incidence on the horizontal thinking the could make the tail fly higher, and you just couldn’t convince then they couldn’t.

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29 minutes ago, A64Pilot said:

If say for example the elevators are mismatched it will create drag as one will be up a little and one down a little to cancel each other out.

Is it enough to measure? I don’t know, depends on how bad it is.

Playing with rigging on a crop duster I learned with the ailerons both slightly up it was slightly faster, roll rate increased and control forces were lighter, and by being slightly up, you slightly washed out the wing making it less likely to tip stall.

It also may have made it so it took slightly longer ground runs and slightly increased stall speed, but I didn’t measure either.

Many will argue rigging won’t make much if any difference as the flight controls will be positioned where they need to be, but experience has shown otherwise.

What got me started on aileron rigging was some were drooping them in an attempt to carry more weight, they were also changing the angle of incidence on the horizontal thinking the could make the tail fly higher, and you just couldn’t convince then they couldn’t.

I have to believe the elevator is rigged that way for a reason, I just don’t know what it is. Perhaps to counter the engine’ offset in level flight?

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28 minutes ago, Shadrach said:

I have to believe the elevator is rigged that way for a reason, I just don’t know what it is. Perhaps to counter the engine’ offset in level flight?

It's not according to the maintenance manual, which shows rigging both sides the same.

I suspect it was just a maintenance oversight somewhere along the way.

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1 hour ago, EricJ said:

It's not according to the maintenance manual, which shows rigging both sides the same.

I suspect it was just a maintenance oversight somewhere along the way.

Odd, it’s been in the family since new. Never been repainted. Tail has never been damaged nor removed. Don’t recall a thing in the logs about adjusting the elevators. I’ll see about adjusting it at annual.

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2 hours ago, Shadrach said:

I have to believe the elevator is rigged that way for a reason, I just don’t know what it is. Perhaps to counter the engine’ offset in level flight?

Mine has no difference that I can detect, often an engine thrust line is offset down and right, the right to counter torque and the down to tame the nose up tendency under power. 

I have heard some aircraft have a very slight offset built into the vertical, but haven’t ever noticed it on any, and of course power off then it would be too much correction.

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