Trim Issues M20J 205 MSE

[Htmlkid]

Just developed a new issue today.... As Im taking off my trim is in take Off position, as I climb I need to trim down a little to keep the nose from going to high... once I get to altitude in order to keep the plane level I have to trim almost all the way down at a cruise of 156kts. Its only after I slow the plane to below 120kts I can finally trim up a little....

 

Any thought to the issue...

 

PS when set to takeoff the horizontal stabilizer is pitched in a slightly down position...

Edited August 17, 2023 by Htmlkid

[BloodRedSkies]

9 minutes ago, Htmlkid said:

Just developed a new issue today.... As Im taking off my trim is in take Off position, as I climb I need to trim down a little to keep the nose from going to high... once I get to altitude in order to keep the plane level I have to trim almost all the way down at a cruise of 156kts. Its only after I slow the plane to below 120kts I can finally trim up a little....

 

Any thought to the issue...

 

PS when set to takeoff the rudder is pitched in a slightly down position...

Mine is an E but it's mostly down in cruise. 

Horizontal stab slightly down I assume mean?  

[N201MKTurbo]

So, this behavior just changed all at once?

When you take off the trim feels correct?

[PT20J]

1 hour ago, Htmlkid said:

Just developed a new issue today.... As Im taking off my trim is in take Off position, as I climb I need to trim down a little to keep the nose from going to high... once I get to altitude in order to keep the plane level I have to trim almost all the way down at a cruise of 156kts. Its only after I slow the plane to below 120kts I can finally trim up a little....

 

Any thought to the issue...

 

PS when set to takeoff the horizontal stabilizer is pitched in a slightly down position...

Let's start with the last comment. The important thing is that when trimmed for takeoff, the elevator should be in trail with the stabilizer. There are bungies in the elevator system so you have to wiggle it up and down a bit but the center point should be very near the in trail position. When it's set this way, note the position of the trim indicator on the console and that will be a good indication if the indicator is correct.

When taking off a M20J, with the normal 15 deg takeoff flap setting, the smoothest way to do it is to apply approximately a 5 lb pull on the elevator during the takeoff roll and slowly release it as the airplane lifts off to establish a climb attitude of about 7 deg nose up. The airplane should be very nearly in trim. When raising the flaps the airplane wants to pitch up so you need to trim down. When you level off in cruise and accelerate, further nose down trim will be necessary. In my MSE, I end up with the trim indicator somewhere between the takeoff band and full down, but nowhere near full nose down. When slowing for landing with flaps, the trim indicator will be somewhere above the takeoff band.

The first thing to check is that the trim indicator is set up right. If something has changed, that is most likely what has changed assuming that the airplane flies right. As a comparison, I made the following measurements on my MSE: Full down trim, the leading edge of the vertical stabilizer is tilted aft 5 deg from vertical and the elevator is about 10 deg trailing edge down. Full up trim, the leading edge of the vertical stabilizer is tilted 1 deg forward from vertical and the elevator is about 10 deg trailing edge up.

 

[DCarlton]

You're getting good advice and I'm not an expert, but I've gotta ask, this is "new"?  Like said above, "all at once"?  Anything suddenly "new" with the trim would concern me.  Interestingly what you describe seems typical to me but I've have to go fly to make sure.  Again, I'm not an expert; just an F owner.  

 

Edited August 18, 2023 by DCarlton

[kortopates]

Sounds all normal. Is the pilot new to his Mooney? Your Mooney transition CFI didn’t help with this?


Sent from my iPhone using Tapatalk

[Bolter]

@Htmlkid if you are new to the M20J, you should note where within the "takeoff" block you put the indicator.  On my J, with typical 2 adults in the front only, I would bias towards the top of the takeoff band.  With a full load and baggage, towards the low end of the band.  Depending on how sensitive you are and how new to the plane, is it possible you area running a different load/CG and feeling those effects only?   

-dan

[Bartman]

If that truly happened “suddenly” I would look at the cable and indicator block. The cable slipped or the indicator head broke off. I’m no expert, but a sudden change in trim indication in a plane that otherwise flies normally is suspected to be the indicator. Another hint, it’s an indicator, not a gauge. 
 

If it takes off with minimal back pressure and in trim with the gear down and flaps at 15deg on initial climb, then that is good. As you decrease flaps you will have to trim nose down. Same for increasing speed.  All that is normal behavior in an M20J.