Broken Fastener Top of Horizontal Stabilizer

Thanks that makes sense now looking at the location. Many thanks!

That may just be an oil hole for the rudder bellcrank, a response to ESM-63. The bakelite bearing tends to swell from moisture and can cause the rudder controls to seize. I have a snap button in the hole at that location.

If it hasn't already been done, take a serious look at ASB-14.

I found a single broken fastener on the top skin of my horizontal stabilizer just in front of the center elevator hinges.  Looking in the parts manual it may be related to the rudder control system - took tailcone off and could not find it  see attached photos - anyone see this before?  You can see the broken screw in the photo it was just sitting in the sheet metal