It looks - maybe like a northern harrier (marsh hawk) They are the only hawks the I can think of with white rump patches and a very long tail. The white wing patches may have been an anomaly of lighting as feathers can reflect sunlight easily...Even crows can look like they have white patches. Or the sunlight could have been shining through the ends. Not sure on that one characteristic but take a look at a male northern harrier - particularly in "in flight" photo.
Mary Alice Koeneke