You guys are hilarious. First, it's "RTV holding on fiberglass fairings will kill EVERYONE! Run! Run for your lives!"
Now, after being repeatedly and soundly proven wrong, it's morphed into "The wrong kind of RTV holding on fiberglass fairings will kill everyone! Run! Run for your lives!"
Spruce sells two types of Dow Corning RTV. The expensive stuff is what we used. I could glue you to the hangar wall with it.
Even if the RTV WERE to come loose from the fuselage, the fairing would be held in place by air pressure. And if that air pressure subsided during landing, the fairing would slide down the landing gear leg, and rest on top of the fiberglass wheel pant.
I *might* have to repaint the gear leg.
Think about this, for a moment: The "standard" procedure to mount one of these things is to use 3, maybe 4 sheet metal screws, screwed into the thin metal at the top of the landing gear leg -- and nothing else. (Rivnuts would be better, but are problematic in that location.) Think about three sheet metal screws, screwed into drilled holes, and those three concentrated stress points under constant vibration.
Now think about a continuous bead of RTV silicone adhesive going all the way around the fairing, attaching the 4 ounce fairing to the sheet metal.
Which installation could you rip off with your bare hands? Which installation has a better chance of failure over time?
Honestly, you guys need to think this stuff through before flipping into panic mode. The Fairings of Death aren't going anywhere for a long, long time -- and only when it's my choice to remove them.
Oh- you used the expensive stuff. It must be good!
Dow Corning makes hundreds of RTV products for different purposes. Some will hold well for your purpose, some will degrade over time. They all need proper surface preparation, application, and cure time/conditions. Like I mentioned, some need moisture from the air to cure. If you used one of those needing moisture, the area under the fairing will take longer to cure since it isn't exposed to air and can't get moisture. Likewise areas where the RTV is applied thickly will also take longer to cure.
Another possibility is that the RTV sets up, but the particular product (remember, hundreds of them) sets up stiff and crumbles under whatever vibration is present at that location. That RTV product may be a strong adhesive for its intended purpose, but not in a vibration environment, where something more flexible, albeit not as strong, might be more appropriate.
Some RTV products are only good for sealing out water and have little strength.
Depending on the product and how it was applied and cured, the 3 sheet metal screws may be the better attachment method over time.
Like I said, I don't know which product you used, nor am I going to look it up; you can just read the label and post it here if you wish. It is possible the stuff you used is appropriate for your fairing.
I like the freedom that comes with experimental aircraft, but with freedom comes responsibility, and part of that responsibility is researching and understanding whether the products used in an experimental plane are appropriate for the tasks expected of them.
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