I read somewhere that birds have no reason to do some aerobatic maneuvers so we won't see them do all our "airplane" maneuvers. And have not been observed doing them. It was an interesting article. I read it years ago when I used to do a fair amount of crow hunting. If you ever want to see what aerobatics are possible from a bird, go crow hunting. BTW, the article I read also said that only the hummingbird hovers and birds won't fly backwards, and both those are wrong.

It sorta makes sense that there would be little or no value to a bird to do an axial roll or even a barrel roll. And personally, I've never seen one do those two. And never seen any bird do a loop and can't think why one would want to do a loop. And I've seen more than one bird fly backwards, but not loop.

We used to have crows hang out at our slopes every once in awhile, and they'd do some stuff, but it was mostly when they were pestering each other. And it seems to me that whenever they needed to loop, they'd just fold one wing and flip laterally. I'd guess that since birds can fold their wings, or just fold one, they'd not really ever have a need or desire to loop with rigid wings. Unless of course, they saw a model airplane loop, and decided to show the model's pilot how to do a better one.