Plagued by dirt dauber wasps in my hangar, years ago I made banana slot covers as those pesky little critters loved to build mud nests just inside and above the slots.  I made a "famous last words" statement at the end of my post: "The sponges do provide some resistance to flaperon motion, but not so great that if they were forgotten and left in place for a flight, I don't think it would lock the controls,  However, I do plan to tag them with "Remove Before Flight" flags for additional pre-flight visibility."

Well, I never quite got around to attaching those streamers and the other day, it came back to bite me.  I had been working all morning doing some maintenance on the plane and was eager to work-in a test hop before knocking off for the day.  A quick glance and I noted the pitot and fuel vent covers were removed (they're all flagged with "REMOVE BEFORE FLIGHT" streamers).  I did my usual run-up, checked controls free and complete range of motion, and off I went.  Perfectly normal flight and when I returned, I spied one of my banana slot covers lying on the runway and the other was nowhere to be found (probably in a neighbor's field somewhere! Ha!).  Then, it dawned on me that I had neglected to remove the covers!

So I retrieved the cover on the runway and made-up another to replace the missing one.  I also immediately ordered and attached streamers! 

BTW. at least I was pleased the covers had performed as I thought they would when I made them - the inside/fuselage side is covered with a felt-like material so that the cover will easily slide with flaperon movement and the cover slot is facing forward so that if the cover is inadvertently left in place, it should easily slide back and off - which they did!

BTW, the outboard side of the cover was left uncovered so the open-cell sponge can grip better.  I had some of those self-adhesive zip tie anchors but their adhesive seemed weak, so I abraded the adhesive side and applied Gorilla Glue to attach them to the sponge.  Gorilla Glue foams a bit as it cures and I figured this foaming action would penetrate the open sponge cells and adhere better - seemed to work great!

So, lessons learned - no matter how much you've worked around your plane that day , do a routine,  thorough pre-flight and don't attach anything to your plane that you don't want to take flying with you unless it has a "REMOVE BEFORE FLIGHT" streamer!!!

John

N750A