flap bearing mod...

[777Dave]

I am the new owner of an RV-4 and my inspector here in Canada is asking me to modify the flap rod end bearing with a bolt and washer arrangement to prevent the bearing and housing from separating from each other. My a/c was assembled as per Van's drawings and I am reluctant to change. Is there any history of problems with a separation of this kind resulting in asymetric flap? I feel that as long as I inspect this bearing on a regular basis to check for looseness and wear, It should be safe.
I have asked Van's the same question.
Any comments appreciated. I have a PDF sketch of what he is asking me to do.

Dave

[Mel]

No history of problems that I'm aware of.

[az_gila]

It is standard design practise to have large diameter capture washers to prevent a total loss of control actuation if a bearing should fail. The design is different in this area due to the use of a bearing with an integral stud.

The Canadians apparently inspect to a higher design standard than the US....

If fact, this question dates back to at least 1996 in Canada, and the fix is easy. See this old Matronics posting... hope the link works...

http://www.matronics.com/searching/g...HOWBUTTONS=YES

Other DARs in the US apparently also agree with the Canadians....

http://www.matronics.com/searching/g...HOWBUTTONS=YES



gil A

[Tom Martin]

Dave
This has been a constant theme with canadian inspectors over the years. Ususally they just accept that the part is installed per plans and let it go. However it is no big deal to purchase a rod end bearing and use a 1/4" bolt with a capture washer installed. This may mean that you will need a slightly larger hole in the bottom of the fuselage to accomadate the bolt and washer.

[777Dave]

Thanks for the info, looks like a call to Van's on Monday for parts...
BTW, is there any down side to this mod other than having to enlarge the cavity in the fuse to accommodate?

Dave

[Tom Martin]

Dave
there is a good chance that you can drive in to Leavons and pick up the same parts, give them a call.

[777Dave]

Thanks Tom, I will certainly do that.
Off to the a/p.

Dave