Rudder pedal torque tubes breaking

[Jerrytex]

Reminder to make sure the Modification has been done on the older rudder pedal torque tubes. Its a shame that a perfectly good airplane got trashed for a relatively minor modification.

So glad that no one was injured.

https://app.ntsb.gov/pdfgenerator/ReportGeneratorFile.ashx?EventID=20160822X85518&AKey=1&RType=Factual&IType=LA

[Shane Alley]

It wasn't trashed. I purchased it from the insurance company and repaired it. I am flying it again!!

[beeryboats]

Two questions. First will the new torque tube kit the 1994 IV aircraft? And is it really a cure to the problem?
P/N?

[Shane Alley]

Yes the new rudder pedals will fit the 1994 IV
You have to call kitfox and they will make them for you.
I just replaced the right pedal Assy. That is only one susceptible to breaking if you fly from the left seat.

[beeryboats]

Yes the new rudder pedals will fit the 1994 IV
You have to call kitfox and they will make them for you.
I just replaced the right pedal Assy. That is only one susceptible to breaking if you fly from the left seat.

If I may be so bold, how much did it cost?
Never mind, I just called, $185 per side. Youch! I may just do the one side too!

[beeryboats]

After more research I may try a weld repair instead of replace. What's funny is very few do the approved repair, sheet metal, glue, and rivets. Most go for gussets and welding. At least that's what I found on the forums. I like the idea. But how "legal" is a weld repair if the SB calls for rivets? Which goes back to a post I put out last night. If I've done a bunch of upgrades to an aircraft not touched in 20+ years, what log book entries are needed?

[PapuaPilot]

If you are talking about working on an experimental aircraft then there isn't a lot to be worried about on the legal side. For an E-AB aircraft you can do any repairs, modifications and upgrades without being an A&P. The main thing to keep in mind is that the aircraft needs to be safe for flight. So if you do the repair using the SB or a technic listed in AC43.13 (such as welding) it would be fine. As far as aircraft records you should record the work that has been done. You can always talk the repair over with and A&P and see what they think (would they be OK to sign off the condition inspection is another way to say it).

The only time you will need an A&P for an E-AB is to perform the annual condition inspection. Only to original builder of an E-AB can be approved to perform the condition inspection. Once the plane is sold only an A&P or IA can sign off the condition inspection. If you are an A&P you can do the inspection yourself, it doesn't require an IA like certified planes do.

BTW I would be perfectly OK with the rudder pedals being welded as long as it was properly done.

[N981MS]

Just what PapuaPilot said.

and

While Kitfox may call it a "Service Bulletin", there is no legal requirement to comply on an Experimental aircraft. It may be wise to comply but it is not required.

Maxwell

[PapuaPilot]

While Kitfox may call it a "Service Bulletin", there is no legal requirement to comply on an Experimental aircraft. It may be wise to comply but it is not required.

Maxwell

The same is true with certified aircraft. No SB must be complied with unless the FAA makes it an AD. Likewise it is wise to comply with some of the SBs.

Many of the SBs these days seem like they are written by the manufacture's legal department. It's a CYA strategy. Unfortunately legal with the FARs and FAA is totally different than with lawyers. :(

[beeryboats]

I've always worked on certified aircraft, mostly Beechcraft, and have never seen a "mandatory" service bulletin. AD's yes, but not SB's. I don't think AD's can be issued to experimental aircraft so the mandatory SB must be their equivalent. Regardless, the mods will be done on mine.

[dholly]

It wasn't trashed. I purchased it from the insurance company and repaired it. I am flying it again!!
Glad to hear it, that was a nice plane and based at my airport. I talked to the previous owner about the SB after my KF4-1200 rudder pedal failed (left pedal, left seat), I guess he didn't take it seriously.

[beeryboats]

I started removing the rudder torque tubes but I thought the bolt head at the end came out and you were done. Guess not! Please don't tell me I have to take out the screws holding the pivot points to the floor.

[Dave S]

Jay,

Yeah.....the bolt goes through a plastic bushing (which you can only see the collar of) which the torque tube rotates on with a washer and nyloc nut on the other end to secure the bushing to the aluminum angle.

The idea is so the friction is between the larger plastic bushing and inside of the torque tube rather than wearing on the tiny bolt.

[beeryboats]

Jay,

Yeah.....the bolt goes through a plastic bushing (which you can only see the collar of) which the torque tube rotates on with a washer and nyloc nut on the other end to secure the bushing to the aluminum angle.

The idea is so the friction is between the larger plastic bushing and inside of the torque tube rather than wearing on the tiny bolt.

So how do you get the darn things out? From what I can see the alum. pivot points have lock nuts on the back side. To get to the inner nuts you have to unskin the front of the belly.

Never mind. I found a seven year old post that had one entry out of four pages where it was explained how to remove the outer pivot and pull out of the bushing.

[beeryboats]

I've been researching some different repairs for this issue. The suggested is the factory sheet metal, glue, and ss pop rivets. Then there is the filet between the torque tube and the upright, and then either one with a wrap of steel around the pedal post and the arm for the cable itself. I was thinking instead of a filet on the side of the post and the top of the torque tube, why not weld it up the front center of both the post and cross tube? Then wrap around the post on both sides of the arm? What I mean the front of the pedal and cross tube is the side facing the pilot. Seems to me the force would be from pushing with your feet and that would be the side that needs reinforcement.

[Jerrytex]

"weld it up the front center of both the post and cross tube"

This is how I did mine and how most of the ones I have seen have been done as well.

[tx_swordguy]

same here on an avid flyer

[Slyfox]

sorry I believe if a person pushes to hard on those pedals they brake. case in point the brakes don't work. the big guy adjusting himself in the seat.

[kitfoxjim]

Most of the comments on this subject concern the weldment between the post and the oversleeve that connects to the rudder torque tube. On my most recent annual 2 weeks ago I noticed that the rivets connecting the sleeve to the torque tube had partially sheered, allowing slight movement between the sleeve and torque tube. These are the stainless steel rivets which in my case did not appear to retain the pull pin which leaves only the hollow rivet to take the sheer stress. I drilled out and replaced the existing rivets with stainless rivets with a monel pin that remains in the hollow rivet greatly increasing the sheer pressure.

I would suggest that everyone check their rivets for tightness. The problem showed up after 725 hours on my Model 5.

[beeryboats]

Most of the comments on this subject concern the weldment between the post and the oversleeve that connects to the rudder torque tube. On my most recent annual 2 weeks ago I noticed that the rivets connecting the sleeve to the torque tube had partially sheered, allowing slight movement between the sleeve and torque tube. These are the stainless steel rivets which in my case did not appear to retain the pull pin which leaves only the hollow rivet to take the sheer stress. I drilled out and replaced the existing rivets with stainless rivets with a monel pin that remains in the hollow rivet greatly increasing the sheer pressure.

I would suggest that everyone check their rivets for tightness. The problem showed up after 725 hours on my Model 5.

Is this the upgrade where there is sheet metal wrapped front and back of the pedal upright and glued/riveted in place per the drawing in the SB?

[kitfoxjim]

I steel wrapped and welded the post to the sleeve so no problem there. The problem I had was that the rivets started to sheer on the torque tube. The assembly is made this way in case it needs to be taken apart in the future.
Perhaps it should have been welded to the inner torque tube?

[beeryboats]

I steel wrapped and welded the post to the sleeve so no problem there. The problem I had was that the rivets started to sheer on the torque tube. The assembly is made this way in case it needs to be taken apart in the future.
Perhaps it should have been welded to the inner torque tube?

I don't have any rivets. Have any photos?

[kitfoxjim]

The rivets I am talking about are #110 in this assembly drawing.

[beeryboats]

Okay, mine are totally different. I have two tubes that set one in front of the other slightly offset. One is both right pedals and the other is both left. Odd, but it works.

[beeryboats]

Here are my templates. Opinions anyone?

[Mruffatto]

Hi berryboat
Can you post a link to the thread? I can’t figure out how they will come out either.
Thanks

[beeryboats]

Hi berryboat
Can you post a link to the thread? I can’t figure out how they will come out either.
Thanks

Not sure what thread you want to see.
Jay

[efwd]

Jay, Look back at your post #14, you mention a seven year old post.
Eddie

[Norm]

Here are my templates. Opinions anyone?

It is the way I did mine except on the cable attach point I used a triangle.

[Guy Buchanan]

Not sure if I'm off topic because it seems this was covered not long ago, but I'll post my mods again. They're welded steel wraps, all joints.

[Dave S]

Guy,

That is exactly what two people at our 'port did with their S5 Kitfoxes.

[beeryboats]

Jay, Look back at your post #14, you mention a seven year old post.
Eddie

I found it! You guys are so needy. Lol. kidding. Here it is:
http://teamkitfox.com/Forums/showthread.php?t=508&page=4

[Mruffatto]

Thanks Jay. I searched and searched for that.
Does that mean those brackets are screwed into nutplates?
If it’s just nuts as I suspect the stainless panel is in my way. Looks like I would have to drill out some pulled rivets to flex that out of my way for access.

[beeryboats]

Thanks Jay. I searched and searched for that.
Does that mean those brackets are screwed into nutplates?
If it’s just nuts as I suspect the stainless panel is in my way. Looks like I would have to drill out some pulled rivets to flex that out of my way for access.

No, I had lock nuts under the floor. I got them out ok, but going back in may be an issue. I'll probably use the magnet at the end of my seal pick to hold nut and washer in place until the threads hook into the nut. I left the inner brackets in place and only removed the outers. I then had to tap them out with a tiny hammer to free them from the inner brackets. Just the bracket and nylon bushing was left behind after the tube came off the inner attach point. Hope that helps.
jay