I've heard of RFs in carry-on luggage for airplanes getting knocked out of alignment. And, it's something I always think about when I pack my camera in the tail case of my motorcycle. I took a CLE to Disneyland with me a couple of years ago. I went on a bunch of rides. I think rollercoaster rides are of such a short duration that it might not be worth worrying about (especially, if you're careful and use a padded camera bag). I was more worried about other things, such as getting distracted with the kids and leaving my camera bag somewhere, spilling something on the camera, or burning a hole in the curtain.
Once, at Six Flags, I got on a water log ride (wet rollercoaster) carrying an M4-P, and as I was entering the 'log" the neck strap for the camera slipped off my shoulder and slid down my arm. I caught the end of the strap with my hand, stopping the camera just at the surface of the water. That got me a nice round of applause. 😛 Yes, these are dangerous places for our special toys!
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