I can't say I've ever seen three Red Tail Hawks perching together. Usually they are solo. Occasionally a pair perch or soar around the sky. They must have some family planning plans.
In 2012 I saw a pair on the steeple of the Congregational Church in Wellesley (scroll down to the last picture). Maybe it's my fuzzy memory or simply bad drawing skills but they seemed to overpower the delicate spire and weather vane. But I guess the take-home lesson from this sermon is to be fully at home in whatever preposterous situation you're in. I can imagine that "he" said "Hey, let's hang out at my place. The views are good and there are mice in the graveyard next to the church." "She" was intrigued by his suave demeanor and expensive plumage (this was Wellesley after all!). But, yeah, the accomodations were a little tight (and the mice were safely asleep in their burrows that afternoon) --and, perhaps for a little while, that suited her just fine.