It Crawled Out of the Woodwork - S1-E11
Factual error: When the energy monster kills his entire research staff by stopping their hearts, Dr. Block brings them all back to life (with their minds and personalities intact) by installing pacemakers. But when the heart stops functioning, brain death occurs within minutes. For this to work, he'd not only have to operate on several people simultaneously, he'd also have to be the fastest heart surgeon on Earth. (00:40:00)
Factual error: The General brandishes a six-shooter pistol with an enormous silencer attached to it. He's a career military guy who should definitely know better, so he gets a failing grade in Basic Weaponry 101. Silencers don't work on revolvers. (00:34:50)
Factual error: Outside the warehouse, one of Ballard's men is talking on a car phone. We're not sure who he could connect with, though. The car has no mobile transmission antenna, and in the 60s, it would have needed a very large one. (00:26:00)
Cold Hands, Warm Heart - S2-E2
Factual error: Barton's ship, we're told, has been designed only to orbit Venus, not land there. Yet he somehow lands anyway - on a planet with atmospheric pressure and broiling temperatures that should have crushed and incinerated him instantly. (00:25:30)
Cold Hands, Warm Heart - S2-E2
Factual error: While orbiting Venus, Barton receives instant responses to his radio communications with Earth. At that distance, there'd be a transmission delay: at least 7-8 minutes. (00:25:00)