Thank you for posting those.

If I may make a point here: To state it plainly and simply, this is exactly why we published the Service Directive. The photos show a pre-failure condition. It's not possible to say how long the unit might take to fail, nor is it possible to say why your servo is in this condition, but this condition is exactly what was predicted and is the first step in the potential series of failure events that caused us to decide to take action. In the safety and risk management world, we call your investigation and discovery a success - It's the SD process working as a preventative measure.

In case people don't take these notifications seriously, this is a great example of why it's important to stay up to date on your service notifications (for any airplane type, not just ours). I'm posting Bob's photos inline here just to make them easier for folks to see. They are good visual examples.

I have looked at your pictures. Your servo and bracket appear clean and maybe lowTT.

How many hours on the airframe?

Any idea how servo rod got bent? Rough ground handling perhaps?

Yes, low TT - about 18 hours. Too bad this SD didn't come out a couple of months earlier, as it would provide more data to analyze this issue. Unfortunately, early April I disassembled the plane for painting. I picked-up the actuator assy. from the painter yesterday to address the SD since it was apart. This was how I found it when I picked it up. So, I can not confirm if it was this way when I removed it from the aircraft. For that matter, this was so discrete of a discrepancy that, for all I know, this could have been bent the day I installed it. Face it, it's been sitting around over two years waiting to be installed, and I could have even bent it day one when I snugged up the jam nut. I just can't say.

I am PRETTY sure the pivot point wasn't contacting the bottom of the tail fairing and that my hole was large enough. And I can guarantee the AST dimensions specified in the PAP were right within range before first flight. Again, this was so discrete of an issue that even if I was doing an inspection it's very likely I would have missed it.

So, yes, it could have been that way from day one, but I believe the take away from this discussion is that it's an issue that can occur.

I read SD 00001 and pulled tail cone fairings off to inspect. My threaded shaft is perfectly straight at 536TT. Early-on I added a 2nd jam nut to lock the threaded shaft to the square servo actuator. So, I will following the SD and monitor shaft for straightness thru 1000 hours of operation.

I'm wondering if threads are rolled or cut? AN hardware uses rolled threads to prevent stress concentration.

Jim, I know you weren?t the original builder, but see step 2 on page 8 of the original KAI section 11.

https://www.dropbox.com/s/jvj8ysixx3...ttach.pdf?dl=0

This step covers adjusting the aft end of the servo push rod. You?ve got a lot more thread exposed between the rod end yoke and the plastic shoulder of the servo drive rod than I, so would expect yours to be more prone to bending. But the kinematics of that appear to indicate that your pivot point would not drop as low as mine when the rod was fully retracted, thus be less likely to bottom out on the tail fairing than mine. Making me wonder now if I was in fact contacting the bottom of the fairing? Just another observation. I?ll certainly be very watchful of this area when the plane is reassembled.

Yes, I'm aware of KAI section 11. I elected to add the 2nd jam nut to prevent rotation, vibration, and working of thread in the square actuator. I never run servo to limits - so no jamming at control stops. I have checked trim function apprx 50% more travel up/dwn than used in flight.

I'll keep "tab" on the tab until 1000TT... :D

When I looked from the side it appears to be not bent.
Took it off and WOW it is really bent
166 hrs


https://www.flickr.com/photos/185605.../shares/4b6a0y
https://www.flickr.com/photos/185605.../shares/y235GN

Safety Directive SD-00001
 

I received my new servo from Ray Allen about a week ago. It was then that I learned I needed to order some parts from Van's also.

I got my parts from Vans today. New tray, F-1287A-1, Bag 2670, and another Bag with the AN315-3R and the Bush-BS 188X 313Xv222 in it. I did not receive any rivets. The new tray has doublers that have to be separated and deburred and then riveted onto the main body of the tray. It seems to me that rivets should have been supplied. I also did not get the rubber gromet that protects the wires from the servo when they go throw the tray. I know there is one on my old tray, but I expected a new one for the new setup. Did anyone get a gromett?

Has anyone else received these items from Van's? If so, did you receive rivets?

Thanks.

John

No bushings or rivets are provided. Apparently you?re expected to reuse the bushings. And since you?re not the builder, guess you don?t have LP4-3 rivets. Van?s approves the use of solid rivets in place of blind rivets. I actually used solid rivets when I rebuilt mine. You might find someone on your field that has some solid rivets.

Hello John,
My order from Ray Allen and Vans was exactly like yours. I wanted to change the plug from the micro molex to the D-sub style so the Service Directive identified the bag needed and the tray replacement due to the fixture on the side that holds the D-sub.
I too checked out the parts and would have liked, and paid for, the plastic grommet that holds the electrical from the servo to the plug. Also the two bushings on the pivot points of the new tray.
Once I get the original parts off, 412 hrs, I will inspect the parts I will need to transfer and determine whether I need to order those parts too.
Now the rivets for me was no issue as I had plenty available, and used solid rivets like Bob Y. I can see where the new tray would need those rivets to complete and supplying the 4 needed makes sense. IMHO