In this episode, government terrorists attempt to remotely fly a Boeing 727 into the World Trade Center. The context in which this is displayed would not have been possible, as most 727s were built before the advent of digital Avionics systems. The analog computers inherent in most 727s would not have been able to be used to remotely control the aircraft.
When the Lone Gunmen and Timmy are hacking into the Department of Defense's mainframe, their intrusion is detected, but Byers tells Timmy to "keep downloading". They're downloading a text document (.txt), which would download instantaneously on any contemporary internet connection. However, this argument can be disputed. Dial up internet was the standard in 2001 which had a maximum speed of 56 kbit/s (realistically unobtainable). Downloading a large text file with 250 pages of text at 2000 characters per page ( 0.5 MB file = 4000 kbit ), it would have taken a minimum of 35 seconds to download at a realistically unobtainable speed under normal conditions.