Garmin Yaw Damper - Weight & CG Implications

[oisiaa]

I'm curious about installing a Garmin yaw damper to go with the GFC 500 autopilot. Any idea where the servo is physically installed and what it will do to the CG and how much weight it adds?

My M20C is already pretty tail heavy which is great when it's just my wife and me, but it becomes difficult when trying to add adults to the back seat. Moving the CG any farther aft would essentially limit the back seats to children only. 

Thanks,

[donkaye, MCFI]

6 minutes ago, oisiaa said:

I'm curious about installing a Garmin yaw damper to go with the GFC 500 autopilot. Any idea where the servo is physically installed and what it will do to the CG and how much weight it adds?

My M20C is already pretty tail heavy which is great when it's just my wife and me, but it becomes difficult when trying to add adults to the back seat. Moving the CG any farther aft would essentially limit the back seats to children only. 

Thanks,

The GSA 28 Servo weighs 1.4 pounds and in the Bravo is mounted in the tail section beside the pitch servo.  At that weight the CG is not going to change much.  To me it is definitely worth the price.

[pirate]

This is where my servo is mounted in my C. 

 

 

[oisiaa]

I'm running CG numbers right now and even based on 1.5lbs that far back it's going to seriously limit me.  My wife likes to ride in the back while we leave the front passenger seat empty. As is, I can do 30lbs in the baggage compartment and 40 lbs in the second rear seat; this puts me right at the aft limit with the gear up. It's no issue if she's in the front seat, but that isn't our preferred setup. 

[LANCECASPER]

Tell her that since you're in the front you need to gain 5 pounds and since she's in the back she needs to lose 5 pounds. Everything should be fine . . lol. 

Let us know how that goes.

[LANCECASPER]

8 hours ago, oisiaa said:

I'm running CG numbers right now and even based on 1.5lbs that far back it's going to seriously limit me.  My wife likes to ride in the back while we leave the front passenger seat empty. As is, I can do 30lbs in the baggage compartment and 40 lbs in the second rear seat; this puts me right at the aft limit with the gear up. It's no issue if she's in the front seat, but that isn't our preferred setup. 

Seriously though most airplanes have 1.4 pounds of dirt or dead insects in or on the back half of the airplane. It's not going to make any appreciable difference. Putting a small cooler strapped in the front seat would probably give you enough ballast if you were really concerned. But I wouldn't overthink it too much.

[IvanP]

1 hour ago, LANCECASPER said:

Tell her that since you're in the front you need to gain 5 pounds and since she's in the back she needs to lose 5 pounds. Everything should be fine . . lol. 

Let us know how that goes.

This will fly as well as a lead baloon  Good luck with that.

[Matthew P]

Not sure what else you are having done, but I got the gfc-500 with both pitch trim and YD and by the time everything was done, the change in aft CG was negligible, especially if you DON'T put 10lbs in the hat shelf area.

 

[ArtVandelay]

I'm curious about installing a Garmin yaw damper to go with the GFC 500 autopilot. Any idea where the servo is physically installed and what it will do to the CG and how much weight it adds?
My M20C is already pretty tail heavy which is great when it's just my wife and me, but it becomes difficult when trying to add adults to the back seat. Moving the CG any farther aft would essentially limit the back seats to children only. 
Thanks,

Is the battery in the tail?

I guess short bodies are more sensitive, with 10lbs in hat rack, 100 in cargo, and 200 in rear seat I’m still within limits with just me in front in my J.

[Slick Nick]

7 hours ago, ArtVandelay said:

Is the battery in the tail?

I guess short bodies are more sensitive, with 10lbs in hat rack, 100 in cargo, and 200 in rear seat I’m still within limits with just me in front in my J.

This. I actually go out of my way to load the airplane more tail heavy for improved true airspeed 

I believe on the classic Mooney's, the battery was located up front on the firewall? 

[dkkim73]

15 hours ago, LANCECASPER said:

Seriously though most airplanes have 1.4 pounds of dirt or dead insects in or on the back half of the airplane. It's not going to make any appreciable difference.

Last annual they found a pickled (TKS) frog in my tail cone. 

[oisiaa]

Yes, my battery was moved to the tail. This aircraft has pretty much every speed mod and trick applied to it. There's no free lunch.

[LANCECASPER]

6 hours ago, oisiaa said:

Yes, my battery was moved to the tail. This aircraft has pretty much every speed mod and trick applied to it. There's no free lunch.

This is one of those rare cases on a Mooney where the lightweight Earth X battery might make enough difference to make it worthwhile.

[oisiaa]

1 hour ago, LANCECASPER said:

This is one of those rare cases on a Mooney where the lightweight Earth X battery might make enough difference to make it worthwhile.

Thanks for the tip! I'll consider that when the time comes.

[Scooter]

Have you done a current weight and balance? If the aircraft has been modified or changed it might be cheap knowledge.

[Jackk]

Yaw damper in a light straight wing piston single seems kinda silly to me

[oisiaa]

26 minutes ago, Jackk said:

Yaw damper in a light straight wing piston single seems kinda silly to me

My wife is easily motion sick. 

[ArtVandelay]

Yaw damper in a light straight wing piston single seems kinda silly to me

Over on Beechtalk, they are considered a requirement for the V-tail Bonanzas.

[Z W]

The yaw damper is nice. I'd put it in again.

Maybe double-check your weight and balance? Was the plane weighed, or is it the product of 40 years of + and - by well-meaning A&P's? My former C model was almost impossible to load out of CG, from my memory. Where is your trim on a normal landing? If it's not nose-up and you find it very easy to flare, that's a sign you are running aft CG. If you are lots of nose up trim and still have to pull back hard to flare, that's a sign your W&B numbers might be wrong.

[Pinecone]

16 hours ago, Jackk said:

Yaw damper in a light straight wing piston single seems kinda silly to me

Until you have it.

I remember a flight in a friend's Cherokee 180D.  I was flying from the right seat.  He started muttering and cussing under his breath.   I asked him what was wrong.  He commented that I flew his airplane almost 4 knots faster on the same power setting.  I am glider, tailwheel and helicopter trained and certified.  I use the rudders.

 

[Matthew P]

18 hours ago, Jackk said:

Yaw damper in a light straight wing piston single seems kinda silly to me

Have you flown one with a YD?

[Skates97]

20 hours ago, Jackk said:

Yaw damper in a light straight wing piston single seems kinda silly to me

My wife and I just had this discussion on a flight Saturday. When we put in the GFC500 I didn't add the yaw damper, couldn't justify the extra cost. In cruise I typically stick my foot/boot in between the rudder pedal and side panel to keep it straight and not have to keep constant pressure with my leg. It would be nice to just let the AP do that work. I still might add it one day.

[pirate]

YD.

When I am flying long trips it’s sure nice to have on those bumpy days,  IMC too. 

[Jim Peace]

On 9/13/2025 at 10:43 AM, pirate said:

This is where my servo is mounted in my C. 

 

 

how did you get that tail compartment so clean?  did you do it? want to do mine?

[LANCECASPER]

1 hour ago, Skates97 said:

My wife and I just had this discussion on a flight Saturday. When we put in the GFC500 I didn't add the yaw damper, couldn't justify the extra cost. In cruise I typically stick my foot/boot in between the rudder pedal and side panel to keep it straight and not have to keep constant pressure with my leg. It would be nice to just let the AP do that work. I still might add it one day.

For years the only option for rudder trim was this: http://www.aerotriminc.com/id2.html

Not a huge difference in price just to add the YD on the Garmin now.