Dutch roll tendency

[RV8JD]

Originally Posted by scsmith

In the case of the RV-7, you have the option to put the RV-9 rudder on. This will help some, as long as you keep your feet firmly on the rudder pedals. The bigger rudder wont help much if it is swinging back and forth.

He probably already has the RV-9 rudder on his RV-7. Van's adopted the -9 rudder for the -7s with all kits shipped after 5/20/2002:

https://www.vansaircraft.com/service...ions/sb-2-6-1/

[birddog486]

Originally Posted by RV8JD

He probably already has the RV-9 rudder on his RV-7. Van's adopted the -9 rudder for the -7s with all kits shipped after 5/20/2002:

https://www.vansaircraft.com/service...ions/sb-2-6-1/

Yeah, this is a new kit/build. The tail was purchased in the fall of 2016

[luddite42]

Originally Posted by rvbuilder2002

Keeping rudder fixed ( like Steve already mentioned) helps a noticeable amount in turbulence.

Or actually USE the rudder to make small yaw corrections as they happen. Really kills those oscillations in turbulence and gives you something to do while you're droning along XC.

[sailvi767]

I would probably just let the airframe exhibit the slight Dutch roll before I tried to constantly correct it via rudder inputs. I think some pilots me included could end up making things worse (PIO)and placing unneeded stress on the rudder. I never really found it to be a issue in the RV6 and it?s non existent in the Rocket.

[BillL]

I am going to have to pay better attention in my 7.

[Sam Buchanan]

Originally Posted by luddite42

Or actually USE the rudder to make small yaw corrections as they happen. Really kills those oscillations in turbulence and gives you something to do while you're droning along XC.

I've tried that and after a short time trying to time random swings in turbulence I decide the benefit isn't worth the effort....instead of concentrating on killing Dutch Roll I just keep my feet on the pedals and soon forget it's happening.

[RONSIM]

in turbulence compared to my V-tail Bonanza --- always thought it was trying to swap ends, with me!

Ron

[Mudfly]

Would this help. Not necessarily for the trim function, but looks like it does maintain a slight amount of pressure on the rudder pedals.

https://www.aerosportproducts.com/product/rudder-trim/

[andrewtac]

Most of the above post sound like what a yaw damper does. I have not flew with one in an RV, though I put the support bracket in my tail cone on my current build. Some airplanes I have flown in the damper is to slow to respond (not quite pio but makes it almost worse) others function really well and eliminate Dutch roll or reduce felt yaw oscillations from turbulence disturbances.

[rvbuilder2002]

I wanted to circle back to this to point out that compared to many airplanes RV's are not heavy in tail wag or dutch roll in turbulence.
It does get mentioned here in the forums occasionally but if you do a search you will not find a lot of discussion about it.

They will exhibit it more than some airplanes people are used to flying (particularly if they were high wing because low wing airplanes with higher degrees of dihedral will tend to do it more) because of some of the reasons already mentioned.

Another rather significant one is C.G. position. The further aft the C.G. is, the lower the static and dynamic yaw stability will be.

So it is not something that indicates a problem with the design (all the RV's have proven to have more than adequate yaw stability). It is just something inherent to the design.