Which one? The one made by Ruger, the pet of Bigfoots,or the one they named the war after? Sorry I couldn't resist. To answer your question,no sir, I haven't seen a black colored hawk.
Yeah, for sure. He had all the typical hawk things (fluffy feathers near his talons, body shape, short neck, etc, and he wasn't very young looking (for a hawk), he was grown.
Maybe he was just really dark from getting wet, or molting?
Sure enough a hawk, but not red. Very dark brown at best, but really closer to black.
That looks like a Harris hawk from the southwestern U S. He must have really got after a fast Jackrabbit, and flew over the Mississippi before he knew it. Poor thing must be homesick by now.