Dick,
I gave up on the GoPro and have a Contour +2 which is far easier to set up, adjust and use. The mount is all important, the shorter the arm and the more rigidly it is mounted the less likelihood of shake. I guess that you are mounting in the cockpit of your A109E? There aren't a lot of 'good' spots in a 109, especially with covered panels, so it may need a bit of tin work to come up with a location: maybe in the roof between the pilots?