CLOSED: Unknown Raptor

The past two summers I've had a Raptor going after my feeder birds, with great success. It seldom makes itself visible to me, but I've seen it in flight a few times. It's about pigeon sized, but sleeker in flight, all light/white on the underside, except for a bit of dark on the tail. Rather than perch at treetop like a Red-tail Hawk, it will going into the tree. Any ideas? I can't seem to find anything of this description (that should be) in my area.

Try Cooper's or Sharp-shinned Hawks. Both, especially juveniles, would give a light-in-front impression and both would be more likely to hide within a tree rather than perch out in the open. Size can be difficult but a quick look would make either appear pigeon-sized. They are both predators on birds and like to hang around feeders.

We've both of those here. Guess I've just not seen photos in flight taken from below.
Thanks.

Tiger, Here's a site that shows raptors in flight and you can pick one or compare two.

http://www.virtualbirder.com/vbirder/onLoc/onLocDirs/HAWK/gallery/bkwheeler/index.html

Of course hawks in different parts of the country will look a bit different from one another too.

I don't think it's either of the above mentioned. Except on the tail, there is no color showing on the underside of the raptor in question.

Both Cooper's and Sharp-shinned often appear pale below; the orangey tone of the adults, and the brown streaks of the juveniles, are not always as conspicuous as the books would have you believe.

Resin