This morning as I was walking the levee in Old Jefferson, a Yellow-bellied Sapsucker flew across it heading from the batture into the large shade trees of the Magnolia School. I was not in position to see its white wing stripes. Fortunately, sapsuckers differ from our other small-ish woodpeckers in another way: their profile.
Sapsuckers are noticeably more streamlined than Downy or Hairy in flight. The body appears more attenuated fore and aft and, especially, the wings are longer and more tapered. Downy and Hairy are overall more pudgy, with shorter rounder wings. The difference is presumably linked to the sapsucker's migratory habit, requiring it to be more aerodynamic.
Wing length alone was enough to give away a second Sapsucker a half hour later, as it flew down my street ahead of me, directly away- showing nothing but its lanky strokes.
PS- my first two sapsuckers of the fall!