Always a bit of a worry when someone says he's fixing his plane before you go up
I used to do this sort of stuff in the 70's with a Wild Ariel camera. I had a hatch cut in the side of the crate that I could open and poke the camera out, then I fixed a strap to the camera and hung it on a nail over the hatch. It can get a bit bumpy at low altitudes and you need to know the camera will be OK if you drop it (which you probably will!).
If it's a light aircraft like a Cessna it'll probably have a drop down window. Secure your camera so that it's hanging in the open window and snap away. It'll be a bit draughty and the driver will moan like hell, but that's the price we pay for our art!
Good luck and take LOTS of pix
