How to carry a quadcopter on a bicycle?
I don't own quadcopters nor fly them, but for something of that price, a hard case, filled with foam cut to size, seems to me the obvious choice.


As for how to mount the case on the bike, I'd probably make an S-shaped hanger

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to hang it off the back rack—probably on the right side, so I could still lay the bike down on the left side. Or put it in a handlebar basket or a pannier, if you can get one big enough.

If the case-and-contents is small enough and light enough, you can alternatively carry it in a backpack. For any significant weight, getting the bike to do the carrying is preferred.