My standard camera setting for aerial shots (Pentax DL DSLR) is AV mode (constant aperture, variable shutter speed) and F4 (the smallest F number with the particular lens). This usually results in 1/3000 or so.
The annoyance is that if shooting over the cowling, 9 times out of 10 there is a very prominent prop blade frozen in the picture.
I used to use a polarized filter years ago; it darkens the sky and generally increases the contrast, but I am not sure of the benefit in the most typical scenario: haze. It produces dramatic - almost unreal - results with a clear blue sky and a sunlit landscape.