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Flap fitment/pushrod bolt

Glen P

Active Member
I've just finished cutting the access holes in the fuselage for the flap pushrods. I had the bolts in and out of the fitment numerous times. Afterwards, I noticed on the drawing that the bolt heads are to be on the outboard side of the fitment. That seems incredibly awkward to install and remove. I can imagine it being the safest setup - the skin prevents the bolt from escaping from the fitment - but is that really required for a bolt that's in plain sight? Do people follow the drawing for this and if so, how did you install the bolt from the outboard side?

Thanks
 
Install the pushrods on the flap actuator before installing it?

Would work, but then any time you needed to drop a flap, you have to remove the entire flap actuator, thus increasing the work AND the possibility of incorrect reassembly and/or damage.

Just put it whatever way works best...and check it each annual CI.
 
Flaps

Would work, but then any time you needed to drop a flap, you have to remove the entire flap actuator, thus increasing the work AND the possibility of incorrect reassembly and/or damage.

Just put it whatever way works best...and check it each annual CI.

Isn't there a bolt holding the pushrod at the flap?
Sorry, I've had mine on and off but not permanent.
 
Isn't there a bolt holding the pushrod at the flap?

There is, but the instructions call for "loctite or equivalent to ensure the rod end does not back out of the platenut" so that end will be permanently affixed.

Thanks for the advice, guys.
 
My take

I heard this too, to put the bolt such that it would Not come out if it loosens. But this is just as bad in my opinion. If the skin keeps the bolt from coming out it is probably going to jam the flaps. This is probably worst. I am putting my bolts in with the nuts on the outside. There Are more important bolts that cannot come loose. I think people are overthinking this
 
Cotter pin

How about using a drilled bolt, castle nut and cotter pin. Bolt goes in the way you want and there's no way it's gonna fall out.
 
If I understand it correctly, the bolt orientation is intended to give the rudder cables less chance to get caught on the nut which is thicker than the bolt head.

In point of fact, my rudder cable did get pushed up by the nut once while retracting the flaps during a condition inspection, probably only because I happened to have slack in the cables. It didn’t cause a problem, and probably wouldn’t happen in flight when the cables are naturally tight, but I’m guessing Vans probably had a reason for on the orientation.

Deviate from Vans instructions with this possibility in mind.

P.s. given my experience, I would definitely NOT use a castle nut and cotter pin. If the rudder cable did get hooked over the nut, the cotter pin could easily prevent the cable from sliding off to its normal position and, if so, it would more easily cause the rudder cable to bind.
 
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It appears to me that the reason for the bolt being back to front is that if there is any slack in the rudder cable, then the risk is that this then gets caught under the bolt head, with ugly consequences.
I decided to deal with the root cause of the issue, and suspend the cable out of the way. The housing is just some carefully split air brake line (like the stuff used for the pitot static system) that is held in place at both ends with some adel clamps. The installation was reviewed by 2 licenced aircraft mechanics prior to my final airworthiness inspection who seemed to think it was an acceptable way of resolving the problem and it now has 70 hrs of operation without issue.

Tom.

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That thread is very helpful, Finley. Thanks very much to everyone for their knowledge and guidance.
 
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