Large Birdlike Object without flapping wings

Near Atlanta, GA. I was sitting at my pool when an object about the size of a human being with a dark grey/dark green tint flew overhead. My first thought was that it was a bird or something...however the object's velocity was very quick and there were no flapping wings. It was partly cloudy outside. The altitude of this object was slightly higher than the average bird. It spanned across my view in approximately 5 seconds... so short of time that when I tried to tell the person next to me about the object, it was already too far away.