Invisible from human sight from a single line of view, but O'Hare Airport probably has a phase array or multiple source radar system that couldn't easily be fooled in such close proximity to the terminal.
It's funny, because in places like Russia, Mexico, Norway, China, and Japan, there isn't even a debate about the existence of UFO's. Plenty about what they might be, but zero about the fact they exist.
There is no doubt, that UFO's exist, what they are is always the question. Could this have been man made, by a governmnet? Better chance of that than coming from another planet, but if our government says they have no proof anything other than a cloud existed, and we as citizens have nothing physical to offer ourselves, it simply goes down as a UFO, and under the circumstances the most logical explanation would be clouds, IMO, as the one known undisputed fact is there was an atmospheric condition at the time.
"as the one known undisputed fact is there was an atmospheric condition at the time."
What an absurd thing to say. If you look outside your window right now, there is an atmospheric condition... Duh!
With one eye-witness, I'd agree with you.
The fact that there was an atmospheric condition is not in dispute. The notion that the atmospheric condition could have caused multiple, highly trained, eye-witnesses with several hundred years of experience in aeronautics to see a spinning disc is almost certainly in dispute.
I'll take the eye-witness testimony of a bunch of pilots over the conjecture of a donut-snarfing FAA geek on most days.
I will admit, however, that the FAA official may not, in fact, eat donuts. That he's or she's a pencil-neck government droid, however, is in evidence.