It aired March 4, 2001.
spoiler
A plane gets hacked by gov g-men and remote controlled to fly into one of the twin towers. They narrowly avoid it and clip an antenna on the roof.
How the fuck? I'm stunned! Also, why is this not a regular part of 9/11 memes?
Wild, huh?
It makes more sense when you know that bin Laden had made several attempts to bomb the wolrd trade center over the course of the 90s. It was sorta-kinda on people's radar if they paid attention to geopolitics. The idea of attacking the twin towers for whatever reason was floating around.
This was a thing for years. I think people have mostly forgotten about The Lone Gunmen now. It wasn't especially long lived and never came close to the popularity of X-Files.
Another one is Neo's passport in The Matrix expires on 9/11/01
I remember coming home from school one day, early 90's and none of the local TV channels were working. Freaky stuff. Found out it was because a car bomb had gone off in the wtc basement.
That's true; there were several depictions of the WTC being attacked in popular culture and the media before and around this time. Examples range form Boots Riley's album cover to cartoons (there was an incident in GI Joe or the Transformers IIRC).
What makes the Lone Gunmen instance stand out, to me, is a couple specific details that coincide with the real event and are unmatched by any other portrayal (that I'm aware of), namely, it:
Show creator Chris Carter developed a working relationship with the FBI during the production of the X-Files, which makes it plausible that someone spilled the beans to him about actual goings on.
Whoa.