Great shots Grant, and I love the one with the prop-tip vortices - or are they spiral chemtrails ?!!!!
To get prop movement, a rule of thumb is to work on shutter priority, with the shutter speed set at roughly the focal length of the lens.
For example, with a 300mm lens, set the speed at 1/300th, or thereabouts.
On my Nikons, I set at 1/320th, or slightly less if conditions allow, and shoot at 400 ISO in clear weather.