Stab attachment heads up.

I was reading this thread, concerning the V stab attachment, and wondered it the same applied to my plane, so I contacted Scott and asked about it.

http://www.vansairforce.com/community/showthread.php?t=119095

Here is the actual issue------------

TedsNumberOneSon said:

So I will speculate publicly as to why and be ready to be corrected.

Even with a solid connection it is a bolted connection with the likelihood of some play and flex under flight loads and therefore subject to fretting or wear and the antiseize serves as a durable layer of lubrication to alleviate that effect?

Click to expand...

rvbuilder2002 said:

Correct.

The movement is very slight but still exists.

That is the reason for the castellated nut and cotter pin on this bolt.

Click to expand...

Scott said that this was how both the 10, and the 14 are done.

So, guess I need to go check our attachment bolt, as I am pretty sure I used a lock nut when I put the stab on for the final assembly.

So, all you 10 fliers out there, might want to check and see how this is done on your plane. Specially for those who did not build..................

Take care, fly safe.

Adding to the info Mike has provided...

The development process is under way to issue a Change Memo for the RV-10 construction manual, to specify the use of anti-seize paste on the contact area between the VA-1016 Front Spar Attach Bracket and the VS fwd spar.

This is not a safety of flight issue. More of a part longevity / maint. issue. My suggestion is that it be done when convenient, such as the next condition inspection.

Scott,

Do I understand that you actually want these two parts to be moving and sliding over each other by design, rather than grip and transfer a load?

Antiseize is usually something I hate, except for some galvanised bolt/nut situations in a marine environment. It usually promotes fretting corrosion and damage to shaft/hub connections around keyways etc.

You now have my brain cell (singular) buzzing! I can't recall what we did in there.

rvbuilder2002 said:

This is not a safety of flight issue. More of a part longevity / maint. issue. My suggestion is that it be done when convenient, such as the next condition inspection.

Click to expand...

Scott, thanks for adding this--------I forgot to ask that question.

RV10inOz said:

Scott,

Do I understand that you actually want these two parts to be moving and sliding over each other by design, rather than grip and transfer a load?

Antiseize is usually something I hate, except for some galvanised bolt/nut situations in a marine environment. It usually promotes fretting corrosion and damage to shaft/hub connections around keyways etc.

You now have my brain cell (singular) buzzing! I can't recall what we did in there.

Click to expand...

It is not that we want the parts to be moving, but by design it will happen because of the engineering design choice of a single point fastener.
Friction of the parts on each other is not a reliable transfer of load in this type of a structural joint. The load is transferred through the fastener (bolt).

There is a minute amount of movement at the rear wing spar attach joint also, when loads are applied and removed from the wing. During most flight conditions the movement is so small it would require special techniques to measure it. At very high G loads, there is enough wing deflection that it would be more measurable.
This is one of the reasons the rear spar joint on all RV models (except RV-12) also uses a castellated nut and cotter pin on the bolt.


There has never been any indication that anti-seize is needed at the rear spar attach point. There has been some indication that after a long term in service, anti-seize would be a good idea for the fwd vertical spar attach joint on an RV-10 or 14.

Not sure how anti-seize would promote fretting. That is in part what it should help prevent.

I have wondered about those castle nuts a few times. When this thread popped I thought it through and....yeah duh.