Running out of elevator trim..

[WardHolbrook]

Sorry guys for pulling up an old thread.

My issue is I'm running out of down trim in cruise.

I could use another 1/8 to 1/4 turn on the trim wheel.

I have to hold the yoke down just a little bit. It's not a lot...it doesn't jump up and start climbing like crazy...its just off by a hair.

My flying partners are experiencing the same thing with one passenger and with a full load.

I'm wondering if the trim assembly or trim screw rod (not the trim wheel itself) is adjustable?

 

thanks

Vic

You need to look for the cause of this. It's not normal. Check motor mounts and rigging to start. 

[Guest]

Is it too late to suggest the obvious? Take it to a service centre who will have the correct travel and rigging boards for your Mooney. They will be able to check and correct the rigging.

Clarence

[carusoam]

V,

Is this a recent challenge? Or it's been this way for a while?

There isn't an old ADF wire antenna holding the tail in place?

My C had the ADF wire replaced at an annual. The "too short" spring tied the tail up as the spring ran out of length.

No matter how much trim was used, the tail was suspended by it's antenna wire, when trimmed down...

This is an example of thinking outside the box, looking for what may have changed.

I don't think Js have the old ADF wire.

But, I am thinking that something may be impeding the full travel of the tail.

And, Mooney specific mechanics are best for this unique area...

Ward has rephrased the challenge, and Clarence has given a great solution.

I'm glad you took the time to revive the thread....

It is definitely not normal to run out of down trim.

Best regards,

-a-

[yvesg]

Might be dead weight in the tail too... check for bird or rat nests in the tail cone. I found the start of a nest there yesterday before a flight. I did put some foam plugs to prevent access but the raskals did chip it away.

Yves

[takair]

Was it always like this? Check the tail for tightness. Lift the tail and feel for looseness. There are limits. I imagine that too much looseness in the bushings could affect trim. If this is a new problem, I would have it checked out sooner than later. Would be worth a look in the area where the tail jack screw and hinge is.

[flyingvee201]

My flying partner bought the plane in March 2013, and I joined in May 2013. This plane was not perfect so we've been working on things here and there. The first thing was the manual landing gear took two hands and a foot to bring the J-bar back in a locked position in the panel. We got that fixed!...smooth as butter now.

In short....we haven't had a lot of time to take her out for long periods until recently.

I think the node down trim was always there from our limited time frame point of view, we just been working on other maintenance items first.

I also notice that my prop is sagging. 

Note: This plane has a newly overhauled motor (70 hours SMOH), engine mount and "B" type prop hub and new Hartzell blades.

Im thinking they forgot to put the shims in the motor mounts. The mounts are new.

I will look at the free play in the tail. I have a feeling that might be it.

I noticed the rudder has a lot of slop in it when I first washed and waxed it.

 

I can tell ya one thing....that motor is very very smooth.

This plane has a LOT of speed mods for an F model. At a glance, it looks like a J.

Even the panel is modified. (Mod Works)

[jkhirsch]

Well you've done it Vic! You've made the old F just too fast...you're simply out of trim.

[Hank]

Check the tail jack screw for old, hard grease; clean it out, refill and set properly. It will probably be in similar condition to the J-bar, for the same reasons.

[Guitarmaster]

I have the same issue (not enough down trim) with my "F" when I hit around 175MPH indicated.  Could use a little more up trim on the landing also.  However...

I did notice the plane is very close to the FWD CG limits with the two front seats occupied so it kind of surprises me that nose-down trim is an issue.  It does land considerably easier with my two not-so-small kids in the back.

At full nose-up trim, the indicator falls somewhere between the TO and NOSE UP position.  I find that a little odd.

[flyingvee201]

Yeah, Im thinking that is the issue too (old grease) as well as giving the area a good visual for bird nests, twigs, etc.

She sat outside for first few months we had and those dam starlings pooped and made nests in every crevice they could find.

 I did find a nest in the tail and tried my best to pull it all out.  I need to get a light in the side access panel and check it all out.

 

Thanks for everyone's suggestions.

[flyingvee201]

Yeah, its fast for an F!  :-)

[carusoam]

Sounds like the trim stop might be a chunk of dried/hardened grease...

Good news, that's easy to clean, sort of...

Best regards,

-a-

[tomn]

Yeah, Im thinking that is the issue too (old grease) as well as giving the area a good visual for bird nests, twigs, etc.

She sat outside for first few months we had and those dam starlings pooped and made nests in every crevice they could find.

 I did find a nest in the tail and tried my best to pull it all out.  I need to get a light in the side access panel and check it all out.

 

Thanks for everyone's suggestions.

I had a bird make a nest in my tail several years back inside the hanger.  The previous owner had made a set of foam triangular wedges covered with fabric and tied together with rope to stuff in the opening on either side in the back to keep birds out.  I now carry them with me whenever I travel and the plane has to sit outside for a while.  I install those along with cowl opening plugs - works great.

[scottfromiowa]

+1 for bird nest....They went through the bulkhead and opening tail round access was only way to see. One piece of stray on elevator and one on ground were only clues...

[flyingvee201]

V,

Is this a recent challenge? Or it's been this way for a while?

There isn't an old ADF wire antenna holding the tail in place?

My C had the ADF wire replaced at an annual. The "too short" spring tied the tail up as the spring ran out of length.

No matter how much trim was used, the tail was suspended by it's antenna wire, when trimmed down...

This is an example of thinking outside the box, looking for what may have changed.

I don't think Js have the old ADF wire.

But, I am thinking that something may be impeding the full travel of the tail.

And, Mooney specific mechanics are best for this unique area...

Ward has rephrased the challenge, and Clarence has given a great solution.

I'm glad you took the time to revive the thread....

It is definitely not normal to run out of down trim.

Best regards,

-a-

:-) thanks!   I dont have an ADF or ADF wire antenna but that is a good point. I will take a look inside the tail and probably will find some dead bird wrapped around the trim screw!!  You would think it would start to STINK by now!   But..seriously..I will open up the inspection panels this weekend and look at the trim screw (oold grease) and inspect for any nest debris.

[N201MKTurbo]

What you need to do is remove the bottom panel below the trim wheel and verify that the little screw under the trim wheel is making it to both stops. If it is then there is nothing binding in the tail. The problem is likely that someone took out the jack screw and got it out of sync with trim wheel.

 

Is your take off trim setting correct? It should be trimmed for best climb speed with the flaps down two people in the front seats and full fuel. If the T/O setting is off it would be indicative of the wheel and jack screw being out of sync.

[flyingvee201]

Now that you mentioned it....The T/O feels like too much nose high trim. I always have to trim it down to stay at best climb speed.

 

Thanks for the advice. I believe someone else mentioned it as well.

I believe there are several items I need to check to make a determination of what the issue ... or issues are.

 

Thanks again guys!