Not sure if you have the 25FB or 25RB as we do. Not a repair, but we added a mirror from Ikea to the wall, moved the travel clip to the other side, and moved the towel bar over as well. Maybe you could move your mirror bracket up or down enough to get solid material, and use a matching wood putty to patch things up.
Hard to say why this came loose, was swing arm stored in the little travel clip when moving? Things coming loose in the Airstream are symptoms of too rough a ride from hard tires on rough roads, or out-of-balance tires or running gear primarily. The weight distribution system should be adjusted correctly to distribute the load among the truck and trailer axles. The weight distribution bars should be tapered so they are flexible. The truck suspension should not be stiffer than you need to carry your loaded Airstream and a reasonable amount of gear in the truck (your Airstream Owners Manual cautions of this). The truck tires should not be to rated far above your needs.
Keep an eye out. If there is further evidence of too rough a ride, you might look at these items to improve it. On the advice of some commercial members here (Inland Andy and Andrew Thomson) we began looking at each item when we bought our Airstream in 2011, set it up with this in mind, and in thousands of miles each year have never had anything break or come loose.
On the other hand, maybe the darn thing just broke from whatever and needs fixing.
Doug and Cheryl
2012 FC RB, Michelin 16, ProPride 1400
2016 Ram 1500 Laramie Crew Cab 4X4 Ecodiesel 3.92 axles
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