Monday, January 2, 2023

Locked gate saves plane.

I've been flying the Pathfinder a lot lately. It has been flying very well. We went to the park and found the gate locked so we went home. I had removed the spray bar for cleaning and was going to re set the needle for flight at the park. At home I figured I could run the engine and get the setting close without flying. As the engine was running I noticed the flaps and elevators flopping around more than usual. After a short inspection I saw the flap control horn had broken. I shut the engine down and started to figure how to fix the broken horn. Had this happened in flight I would have had no control and crashed. The vibration had fatigued the metal to failure. Possibly the metal had been chrystalized during the brazing process. Either way
it was no longer usable and had to be repaired somehow. My first option was to install a plastic horn like the one that comes with the kit. Then I rembered that I could make a horn out of aluminum angle that would be much stronger and work just as well or better than the broken part. The plans show a horn that should give better performance so I duplicated it on the aluminum angle. Some hacksaw and file and drilling work and the new horn was ready for installation. I used 4 screws to hold the new part on the flap and a piece of plywood underneath for the screws to anchor in. The weather isn't cooperating right now but may get better a bit later for a trial flight, if the gate isn't locked.

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