95% coop/run, 5% free range here.
Over the years, I have literally lost EVERY one of my hens to Red Tail hawks, except for two. Well, three actually. One was killed by a mangey fox that moved into the barn. The other two are still with me. All the others (anywhere from 4-10 hens per year) were killed by the Hawks. I have come home to see hawks eating my chickens right on the driveway.
We built a very large, really nice run - it's 24x27x6 feet high. It is partially roofed in steel, and the rest is bird netting. They have a huge indoor chicken house that is extremely secure. They have free access to the house during the day, and are locked in there at night.
I will ONLY let them free range when I out there a couple hours in the evening before bed. I had a Red Tail try to swoop in and take a chicken last year while I was standing RIGHT THERE. He almost slammed into me in his swoop.
I use mealworms and my birds come RUNNING when they see I have the mealworm bag. I constantly keep bringing them back up close to the house or the barn, and feed them treats, and I hardly ever turn my back on them. One day a week or so ago a hawk swooped right over where I was sitting under the apple tree feeding them mealworms. They jumped into my lap and huddlled around me as tight as they could. The hawk made two passes directly above us, looking for an opening to come grab one.
FREE RANGE IS NOT AN OPTION HERE. All the sparkly stuff, livestock dogs, geese, and electric fences in the world will not protect you from mature, breeding pairs of Red Tails hungry to feed their young. Once they figure out you have a free buffet, they will NOT leave your property. But over the years I have discovered that they aren't active in the late evening nearly like they are in the morning. The day last week they swooped us, it was early afternoon - like around 2 p.m. or something, I knew better than let them out, but they wanted out SO bad. But if I turn them out really late, I never see the hawks, but I still stay out there constantly.
People say Red Tails can't attack if they don't have a clear open flight path to dive in. NOT TRUE. I have watched the Red Tails sit on top of the silo and nab pigeons as they come out. No swooping, or diving required. I have also seen a Northern Harrier sit on the ground under a bird feeder and grab them underneath a bush. I saw a Red Tail sitting on a stop sign, hop down and nail a mouse on the ground right under the sign. They are very efficient predators. If you plant a bunch of trees and bushes for cover, they will just perch in your bushes and hop down on top of your chickens. Their preferred method is slam into the back and break their neck, but they absolutely will eat prey alive if that's the only way they can grab them.