Joe Schmucker <> writes:

I was doing a preflight on my Exxtacy yesterday and I found that a critical component seemed to have gone *missing* from my glider.

In the center section where the wings connect to the keel, on my glider there are two "conical" shaped retaining plugs that join the right wing to the keel. They are fitted with pip pins so that you can easily remove one of the D-cells (for a long carry-in I guess...). The pip pin on the bottom plug was missing!!! How could that happen??? My first thought was that someone took it because they needed one in order to fly. I thought, geeze, no problem, it's just a pip pin, but you could have left a note!!!! If that plug were to fall out, I would definitely have a catastrophic failure.

Then I think I figured it out. When you unfold the wing, those lugs have to be able to rotate. I've noticed in the past that they are REALLY TIGHT. I had to use a c-clamp and a custom jig to push it out when I had my keel repaired. I believe that the top of the head of the pip pin was broken off as the wing was opened because the plug was tighter on the wing component than on the keel component causing the pip pin to be rotated into the keel. I think the top of the pip pin is aluminum and is somehow fitted onto the shaft of the pin by friction so if it was "pushed off", the shaft of the pin would easily slide out of the opening.

So, beware. Check your pip pins! I'm actually going to replace the pip pins with a standard pins and a retaining rings. It is possible for the failure to occur in mid flight. The pip pin might LOOK fine when you do your inspection, but it could be on the verge of falling apart.

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