Factual error: When they first go EVA to look at the satellite, Eastwood goes into the Shuttle cargo bay to put on his Manned Maneuvering Unit (MMU). He goes outside without being tethered at any point. Even when deploying an astronaut in a MMU, the astronaut remained tethered until he was safely mounted into the MMU, then the tether was removed. Upon his return, the astronaut was again tethered before he dismounted the MMU.
Factual error: The Russian says that the missiles in IKON are locked onto American cities. The implication is that those cities will be destroyed if Eastwood screws up. Actually, since the orbit has decayed from geosynchronous (an altitude of roughly 22,000 miles) to low Earth orbit at 1000 miles, I don't think the missile guidance systems would get a chance to work. If the missiles were launched, they would simply shoot down toward the Earth and blow up wherever they happened to be. So, prayers to anyone unlucky enough to be directly below those missles.
Factual error: When the super fortress has a near miss with one of the x-plane pilots the pilot should be in free fall and not appearing to float motionless as the super fortress passes by.
Factual error: Several times in the film you see astronauts "suit-up" and head straight out the airlock into space. In reality they would have to pre-breathe pure oxygen for forty minutes to purge the nitrogen from their bloodstreams. If they just went straight out they would suffer from "the bends", as divers do.
Continuity mistake: The US flag that was in the back-left corner of Gerson's office (between the map and the window) when Colonel Corvin first visits to offer Team Daedelus' service is gone later on, when General Vostov is in Gerson's office. (00:34:25)
Factual error: After bailing out one of the pilots somehow suspends his free fall and is almost hit by the B29 while motionless in midair.
Factual error: Clint Eastwood and Donald Sutherland go scooting around in open space (admiring a view of Italy on the sunlit side of the Earth) with their gold solar-screen visors retracted wide open. To avoid accidental instant blindness, real astronauts would never open their solar-screen visors during EVA on the sunlit side of the Earth; yet the astronauts in this film do it constantly, with no ill-effects.