The Wrong Stuff - January 24, 1961 - S4-E7
Factual error: Al says he was an astronaut and flew around the moon, describing a mission that sounds precisely like Apollo 8 (10 orbits around the moon, reading of Genesis, etc). In the season 2 finale episode 'MIA, ' set in 1969, Al says he was shot down in Vietnam two years earlier, in 1967, taken prisoner and not freed until 1973. The Apollo 8 mission flew in Dec. 1968, meaning Al would have been a POW at the time. Also, NASA astronauts aren't generally sent to serve as pilots in active war zones.