It is quite possible. Don't forget that they were 106 floors above the city at impact, so those heads might have traveled even farther but for hitting the high suspension cable tower over the bridge.
John Bobbit's severed penis flew 34 feet when Lorena tossed it out the window of her moving vehicle, near a busy Virginia intersection. As I was driving in the opposite direction and the severed penis hit my windshield, my wife said, "did you see that bug?" To which I responded, "No, I was too busy looking at it's cock."