Do you see the bold, conspicuous, white arcs around the eye? Have you noticed that the upper and lower arcs do not join up, and that the upper arc is broken?
When I see one flying away from me, and I cannot see the brick-red breast, I can still tell that it is an American Robin by the shape and the white at the corners of the black tail.
Look for these field marks the next time you see robins, and you will learn to ID this bird in flight.
photo © adrian binns