Previous puzzle of this kind: #1
A bird without wing, body, feet or tail,
An invention am I who can effortlessly sail.
I am unlike my lowly brothers who only deliver mail;
Surging over the winds I am majestic without fail!...Alas, that is a lie, I do have one shortcoming
In order to be useful to you I cannot be made thin.
Thanks a lot, you, you darned and cursed thing!
Now there are barriers I shan't break, oh, races I'll never win!You say that there's a Wikipedia article for anything?
Find mine, then, and declare yourself this puzzle's king!
Hint 1:
My stability was an issue that my creators did see
That is the reason why they taught me to sweep.
Hint 2:
UFOs have a generic shape;
I do too, though not from space