Rip Hunter tells Gideon to set a course for Star City, January, 2016.
To this, Gideon responds, "Ah, the early second millennium A.D...."
The year 2016 is a part of the third millennium A.D., since the first millennium was from the years 0-999.
Vandal Savage is seen stealing a nuclear warhead from Norwegian soldiers. Norway has never had nuclear weapons, nor has it allowed allied nations to store nuclear weapons on its soil.
Incorrectly regarded as goof. Just before the team arrives in 1975, 2 guys are killed by Chronos warrior. One of them refers to him as being "so Darth Vader". The first Star Wars movie wasn't actually released until 1977. However, this scene is not from 1975, but from 2016 at the Wave rider's landing spot. The 2 are driving a beat up 1999 Neon.
At the beginning of the episode, when Rip assembles the team on the rooftop, Carter and Kendra say they have reincarnated many times in previous lifetimes. Sara replies to it by saying she has done that before. This is wrong. Sara went through resurrection, which is considerably different from reincarnation.