Oddly (normal for me) I decided that with all the things I own that
will plug into a cigarette lighter, it made sense to me to mount a
cigarette lighter socket in my glider.

I tried that first, but found that the cigarette lighter socket that I
bought was not secure enough to trust in turbulence. I also didn't want
the USB wire bundled up and hanging off the instrument panel. So now
things are hard wired, bundled and behind the panel with only a few inches
of USB cable hanging out to plug the 310 into.

Brian