Bird In Flight

Hi I have a rigged bird that I wish to animate as if flying but the problem is everything I dod ends up very unrealistic. So basically what I need is some kind of resource or diagram on the flight of birds, specifically a bird with long wings like an albatross.

birds with long wings are usally sailing. so they don’t move their wings much.
first try to nail down this sailing look and than an occasional flap of the wings if the bird looses height.