Charles Ellicott Commentary Leviticus 1:17

"and he shall rend it by the wings thereof, [but] shall not divide it asunder; and the priest shall burn it upon the altar, upon the wood that is upon the fire: it is a burnt-offering, an offering made by fire, of a sweet savor unto Jehovah." — Leviticus 1:17 (ASV)

And he shall cleave it with the wings thereof. — Before placing it on the altar fire, the priest made an incision in the wings, without, however, separating them wholly from the body, thus corresponding to some degree to the limbing of the quadruped .