Factual error: Peter Townsend wears the rank insignia of a group captain (and is referred to as Group Captain Townsend) from the beginning of the series in 1947. In fact, Townsend was promoted from wing commander to group captain on 1 January 1953. He was also appointed Commander of the Royal Victorian Order (CVO) in 1947, but is never seen wearing the appropriate medal ribbon, which should come first on his collection.
The Crown (2016)
1 factual error in Season 1 generally - chronological order
Starring: Matt Smith, Claire Foy, Vanessa Kirby, Victoria Hamilton
Continuity mistake: As Philip paints his parrot, its head can be seen half-painted. When Parker enters the room and the camera switches focus to him, the head can be seen in the background fully-painted. However, when the camera returns to Philip, the parrot's head is again only half-painted. (00:24:42)