So, if you're lucky enough to have a newer model airstream, you may have run into this... the adjustable A/C ceiling vents used on Airstream trailers 2015 and new are great in that they adjust, but not so great in that they are prone to falling out and crashing to the floor, or possibly your wife while sleeping in bed. In my particular case, the issue is the hack-job done to create the holes in the aluminum skin and the plastic tabs on the vents that don't always stay clicked-in and the resultant force of gravity pulling them down. The following is my fix for this, leveraging some relatively cheap hardware and a bit of elbow grease.

Supplies

Supplies:

I found all of this at my local Lowes and have links to them below, but any local hardware should carry these items:

Hardware: I bought stainless to ensure it matched the vent, depending on the # of vents you need to fix, your quantities will vary, but you'll need one of each for each vent:

Tools:

This is a pretty basic repair, so just a couple tools needed:

Hacksaw (for cutting Aluminum to length)
5/16 Regular socket nut driver
11/32 Deep Socket nut driver
5/16 Drill Bit and Drill
Phillips screw driver
Flat-head screw driver

Step 1: Remove Vent Cover

If it hasn't fallen already, removal of the vent is pretty easy they just snap out, sometimes they have slots to make the tabs come off easier, so turning the vent slightly until 2 of the tabs release makes the vent come off by simply pulling down on it. Once removed you can see from the backside there is a rivet that holds the vent cover, the diffuser and the adjustment slide together.

Step 2: Removing the Rivet

So to remove the center rivet, use the 5/16 drill bit on the backside (not the shiny vent side) and drill out the rivet until the tiny washer comes loose, don't worry if you go to far, the center vent diffuser will also get drilled out later. Once the washer spins off, you can simply use a flat-head screwdriver to pop the two plastic pieces off the rivet. Once the plastic pieces are removed, push the rivet (may require a tap with a hammer) through the SS vent piece. If the rivet is still flared a bit, you may need to use a pair of pliers to work it the rest of the way through.

Note: There are black-plastic bushings between the vent adjuster and the diffuser and cover, make sure not to loose these as they will be reused when putting it back in.

Next: Drill out the holes in the plastic pieces and the vent cover to ensure the new pan head screw goes through easily.

Step 3: Building a Better Bracket

So taking the 1/2 Flat stock aluminum, cut a piece 7" in length and put a hole in the center (3.5" from each end). This will be used to mount the vent from the backside and inside the vent duct (so no need to be pretty).

Step 4: Attach Screw to Bracket

Using the Pan head screw and the hex nut, put the bolt through the aluminum flat stock and tighten it using the hex head screw.

Step 5: Reinstalling the Vent

Install the bracket into the vent hole, as you can see in my instance the hole cut at the Airstream factory was not perfectly round contributing to the issue of the vent falling. Re-install in the order you took the vent apart:

Add the plastic diffuser
Add one of the black plastic washers
Add the plastic vent flow adjuster
Add the second black plastic washer
Add the vent cover
Add the tiny black vent washer
Add the Acorn screw nut last

Once you've assembled these you can use the nut driver to tighten it all down, it may twist a bit at first, but just keep tightening the nut until it's snug but do not over tighten as it will limit the ability to spin the vent cover to direct the airflow. If desired, I did this, you can add some loc-tite thread-locker to the acorn cap to ensure it doesn't vibrate loose while traveling.

Hope you find this helpful, I've tried several ways to prevent these from falling, from heating up the tabs and bending them out, to zip ties, and found this to work the best so far.

Happy Travels!