rudder play

[JoshMan]

Hey, guys. Question about rudder play I just noticed on my E model tonight.

Was pre-flighting for a flight tomorrow and noticed as i moved the ailerons up and down with my hands the rudder moved slightly as well. The rudder definitely has more play than it did a flight ago.  I can freely move it about 1-1.5 inches left to right.  I attached a video but don't know if it will work or not.  Any thoughts? I know some play is normal but I have never seen the rudder move with aileron movement.

Video.MOV

[Immelman]

If the airplane were jacked up the behavior you observe when wiggling the ailerons would be normal: there is a spring interconnect between rudder and ailerons that aids in turn coordination. However, in a perfect world on the ground you would not see the rudder move as its connected to the NLG which is stationary under the weight of the nose.

There are a whole mess of rod ends etc between the rudder and NLG steering. When you see that kind of movement, or can wiggle the rudder on the ground as in your video, you are wiggling one end of the system. At the other end of the system is the NLG tire firmly stationary on the ground. All that play at the rudder is additive and represents the sum of the slop in the many links along the chain.

If the behavior of the plane just recently changed, perhaps only one became worn or loose; that might be fairly easy to fix. If your plane was like mine, it was just showing its age, and several parts had to be replaced to tighten things up. For example on my most recent annual, my IA caught some slop in that very last bearing at the rudder. You could see it by holding the rudder in one hand, and the rod connected to it in the other and wiggling... a very small amount of slop was present due to that bearing becoming worn. That was a very easy and inexpensive fix... but this wasn't the first part we replaced and I have a feeling it won't be the last.

The way to diagnose this is to jack the airplane, get on your creeper, and take your time going through each connection to isolate the slop. Hold one side stationary and wiggle the other.. observe what's moving. If I were to guess you'd find it somewhere between the rudder pedals and NLG steering. With the airplane jacked, rock the nose wheel left and right and observe what moves before the 'slack' is taken up and that movement goes back to the rudder. The steering horn is a potential target as are the pieces of hardware that connect to it. Once the NLG is out of the way, remove the belly and empenage access panels and go through the pushrods and each rod-end bearing on its way out to the rudder.

Finally I am not sure you can eliminate all of the play. After spending a bunch of time going through mine, the best I could get was down to about 5/8 to 3/4" of rudder play when wiggling as you were.

 

Edited September 23, 2017 by Immelman

[carusoam]

To share the video...  post it in YouTube...

Then copy the link here.

 

This allows a bunch of people that use iPads to see your .mov file...

Best regards,

-a-

[AlexLev]

@JoshManjust curious if you ever solved this and how? noticed some rudder play/slop in my G model as well recently and a recent nosewheel shimmy, wonder if they are related in some way.

[RobertGary1]

I wonder if what you are feeling is play in the nose wheel on the ground rather than the rudder itself. As my plane has gotten older I'm having to replace more rod ends. There is a rod end at the top of the steering horn that seems to want to develop slop. 

 

-Robert

[joekinnc]

Hey Folks - checking in on this - I have some worn bushing and some rudder play on my 69M20F - how do you know when bad is well... "bad"?  How are these fixed? cut rod and re-weld - are spare parts available anywhere?