In a scene at the start, a flight of B-17 bombers is seen passing overhead right to left. The following scene (historical black and white footage) has Luftwaffe fighters shooting down a plane. The plane that is shot down is a 2-engine bomber, similar to a B-25.
When Hogan, Newkirk, and the other prisoner are about to 'escape', Hogan calls Kinchloe so he can move the radio out the emergency tunnel. When Klink arrives at the 'escape' tunnel, the walkie-talkie Hogan used to contact Kinchloe is gone.
When Hogan is talking with Klink about the new guard (Berger), he sits down and prepares to eat one of Klink's sandwiches. It starts out as a wide shot, and the sandwich is in Hogan's right hand. The view shifts to a close-up on Hogan, and the sandwich is in Hogan's left hand. Hogan lifts the sandwich to his mouth to take the first bite, and the view shifts back to the wide shot. Now the sandwich is in both of his hands as he actually takes the bite.
There is absolutely no way that any sort of report about the reporter's experiences with Hogan's group in the POW camp would ever have been printed in an American paper. Even if military censors had not gotten word of this and killed it before it went to press, the newspaper's editor himself would have quashed the story due to wartime restrictions on what might be considered information that could be of value to the enemy and his awareness of the penalties for violating them.
The actor playing Olsen in this episode is not Stewart Moss. The Olsen in the pilot episode (The Informer (1965)), played by Stewart Moss, is approximately the same height as Hogan (Bob Crane) - they are side by side when Olsen returns to camp (he and Carter change places in the truck at the end, during the confusion when the dogs are released). In this episode, the actor playing Olsen is at least six inches shorter (maybe even eight) than Hogan (Bob Crane), and this Olsen has a much heavier build than the Olsen in the pilot. The face on this Olsen is rounder, too.
Two new guards are assigned to Stalag 13, and Klink comes out to speak to them. Hogan and the gang are watching from the side of the barracks, at the door. Carter is sitting on a bench holding two metal plates up to his face, supposedly to help his face get an all-over tan. The problem is that he is sitting in the shade - the only light being reflected on his face is from the production lights, which are casting shadows on the wall of the barracks. The shade from the actual sun can be seen on the ground when the view is a wide shot of all the men in front of the wall. Also, the shade line is visible on Olsen's left shoulder.
In the opening, when Hobson is found, Hogan eventually orders one of the extras to bury Hobson's shoe. However, the parachute is left to be found. This makes no sense, as the parachute would be found more easily than a shoe, and be more identifiable. It also makes no sense to bury the shoe, as the assumption would be that the shoe would probably be useful again when Hobson's foot heals enough for him to travel.