Yaw Damper question in a J

[mhrivnak]

I got the yaw damper in my J and like it. In any turbulence, even light, you can turn it off and on and feel the difference. The ride is noticeably smoother with the YD on. It's not life-changing, but it does marginally improve the quality of life, particularly for passengers who aren't used to being in vehicles that experience turbulence as yaw.

In turbulence, a pilot cannot do what the yaw damper does. It's not like the other AP functions, for example where you can hold altitude yourself, or let the autopilot do it. Yaw damping responds with extreme speed and precision to very small disturbances in yaw, stopping a yaw motion just as it starts. It's impressive technology, and I found it to be a relatively small cost to give my plane smoother rides for the life of the autopilot (hopefully measured in decades).

[bmcconnaha]

3 hours ago, PT20J said:

The yaw damper is not supposed to be an automatic rudder trim. It will keep the ball centered to coordinate turns and compensate for minor out of trim conditions. If you are significantly out of trim, as in a climb if you don’t have rudder trim(or have it but don’t use it), the yaw damper may not be able to center the ball. Even if it can, you are putting needless strain on the servo asking it to maintain a constant torque for a prolonged period. 

Skip

I’ve read all the threads. I was being slightly sarcastic.  I’ve yet to see a GFC500 yaw damper that can keep the ball centered in all phases of flight.  Specifically climbing or descending.  

[rbp]

4 hours ago, bmcconnaha said:

I’ve read all the threads. I was being slightly sarcastic.  I’ve yet to see a GFC500 yaw damper that can keep the ball centered in all phases of flight.  Specifically climbing or descending.  

my level  off in cruise process is to turn off the YD while the plane accelerates at climb power past 140, reducing the power to cruise, centering the ball with the rudder trim, and re-engaging the YD

[ArtVandelay]

Well,based on responses;
1. Those who have a YD says it’s a must have.
2. Those who don’t say it’s not necessary.

Makes sense.

YD option costs about $4,000. So OP has to decide if it’s worth it.

[Fly Boomer]

32 minutes ago, ArtVandelay said:

Well,based on responses;
1. Those who have a YD says it’s a must have.
2. Those who don’t say it’s not necessary.

Makes sense.

YD option costs about $4,000. So OP has to decide if it’s worth it.

Yep.  Just like the latest radio, instrument, ice protection, turbo, etc.

[Pinecone]

9 hours ago, mhrivnak said:

In turbulence, a pilot cannot do what the yaw damper does. It's not like the other AP functions, for example where you can hold altitude yourself, or let the autopilot do it. Yaw damping responds with extreme speed and precision to very small disturbances in yaw, stopping a yaw motion just as it starts. It's impressive technology, and I found it to be a relatively small cost to give my plane smoother rides for the life of the autopilot (hopefully measured in decades).

I disagree.  You CAN do it, but you need to train your feet.

Tail wheel or glider time will help do that.

[Pinecone]

2 hours ago, ArtVandelay said:

Well,based on responses;
1. Those who have a YD says it’s a must have.
2. Those who don’t say it’s not necessary.

Makes sense.

YD option costs about $4,000. So OP has to decide if it’s worth it.

And also very telling.  Those who don't have it don't know what they are missing.

 

[dzeleski]

From garmin:

 

3.1.1 AUTOPILOT AND YAW DAMPER OPERATION

The autopilot and optional yaw damper operate the flight control surface servos
to provide automatic flight control. The autopilot controls the aircraft pitch and roll
attitudes following commands received from the flight director. Pitch, Roll, and Yaw
(if installed) autotrim provides trim commands to each servo to relieve any sustained
effort required by the servo(s). Autopilot operation is independent of the optional yaw
damper.

The optional yaw damper reduces Dutch roll tendencies, coordinates turns, and
provides a steady force to maintain directional trim. It can operate independently
of the autopilot and may be used during normal hand-flight maneuvers. Yaw rate
commands are limited to 6 deg/sec by the yaw damper.

3.1.5 YAW AXIS

The yaw damper uses yaw rate and roll attitude to dampen the aircraft’s natural
Dutch roll response. It also uses lateral acceleration to coordinate turns and reduce
or eliminate the need for the pilot to use rudder pedal force to maintain coordinated
flight during climbs and descents.

I dont need to touch my pedals in my plane once the AP is on and I do not have rudder trim. I take off, get somewhere around 800-1000ft and turn the AP on and take my hands and feet off of the controls. I have not tested at a very steep aggressive climb but at a normal cruise climb of 100-120mph I dont need to add any peddle pressure.

[ArtVandelay]

And also very telling.  Those who don't have it don't know what they are missing.
 

But they can always add it later, fairly easily: install the servo on existing bracket, tap into the nearby Can bus, and reconfigure.

[WaynePierce]

6 hours ago, ArtVandelay said:

Well,based on responses;
1. Those who have a YD says it’s a must have.
2. Those who don’t say it’s not necessary.

Makes sense.

YD option costs about $4,000. So OP has to decide if it’s worth it.

I think the OP will probably have it pre-wired while they're in there replacing the old servo's and wires. Then when he can afford to do so have the YD Servo purchased and installed...

[kortopates]

Certainly can add it later, but it won't be trivial. Garmin has its own hardware and brackets for each servo, nothing from my KFC-150 was reused, but most hardware used by Garmin was very similar to the BK AP. 

[WaynePierce]

1 minute ago, kortopates said:

Certainly can add it later, but it won't be trivial. Garmin has its own hardware and brackets for each servo, nothing from my KFC-150 was reused, but most hardware used by Garmin was very similar to the BK AP. 

And to make matters worse, Garmin no longer sells the hardware and brackets as a kit with the AP. Those have to be ordered separately. I think each servo/bracket is $2500.00ish.

[PT20J]

1 hour ago, WaynePierce said:

And to make matters worse, Garmin no longer sells the hardware and brackets as a kit with the AP. Those have to be ordered separately. I think each servo/bracket is $2500.00ish.

Doesn’t the yaw damper servo go beside the pitch servo on the same bracket that has to be installed for the basic autopilot?

[WaynePierce]

26 minutes ago, PT20J said:

Doesn’t the yaw damper servo go beside the pitch servo on the same bracket that has to be installed for the basic autopilot?

I don't know, that will be a question to ask the next time I fly over the the Avionics shop! It's an excuse to fly, I'll take it.

[kortopates]

48 minutes ago, PT20J said:

Doesn’t the yaw damper servo go beside the pitch servo on the same bracket that has to be installed for the basic autopilot?

Although its been more than a month since I was in there looking around so my memory could be flawed, I recall a separate shelf bracket was installed for it. I recall it sat just opposite of the pitch trim servo.

[ArtVandelay]

Don’t know about all models, but this is the picture of the bracket with pitch servo and you can clearly see the other hole for another servo

[kortopates]

Don’t know about all models, but this is the picture of the bracket with pitch servo and you can clearly see the other hole for another servo

yep, i stand corrected, it is just one bracket to support both. So adding it is easier than i was thinking from memory.


Sent from my iPhone using Tapatalk

[rbp]

9 hours ago, dzeleski said:

I dont need to touch my pedals in my plane once the AP is on and I do not have rudder trim. I take off, get somewhere around 800-1000ft and turn the AP on and take my hands and feet off of the controls. I have not tested at a very steep aggressive climb but at a normal cruise climb of 100-120mph I dont need to add any peddle pressure.

the amount of right pedal needed at 34" (climb) versus at 29" (cruise) is about half a ball. I trim off excess pressure with the rudder trim.

[Roger M]

I need to rig the flight controls on my newly accquired M20M.  Can you help me find the

travel boards required?  Rent or Purchase?

Is there a better way to rig the flight controls?

[Philip France 13]

I just installed GFC500 with GTN750 G3X… no YD on my J and it works fine, both in Cruze and approaches big improvement to old KAP150 it follows the line in NAV mode

[skykrawler]

On 12/4/2022 at 10:49 PM, dzeleski said:

When my yaw damp is on I don’t have to touch a single peddle at any phase of flight. Even during climb or decent, the ball is always centered.

LOL.....I fly with guys like that, usually they fly jets that have yaw dampers and forget that rudder pedals are there except when taxiing.

[1980Mooney]

On 12/6/2022 at 8:51 AM, Roger M said:

I need to rig the flight controls on my newly accquired M20M.  Can you help me find the

travel boards required?  Rent or Purchase?

Is there a better way to rig the flight controls?

I think you are new here. This topic is probably not that right one to get people to answer your question. You may get a better response if you post you question to the topic below or else start a new one - specific to your plane/question. @carusoam can help guide you too.