The Safecracker Suite - S1-E27
Continuity mistake: As Schultz is asking about Alfie, saying "Who captured him, the Kaiser?", Hogan's hands are down. A second later, his chin is in his right hand.
Continuity mistake: Major Bonacelli goes to put his hand in his coat for money, he pauses with it in for the next few lines. When Newkirk asks about Germans eating a lot of pizza, Bonacelli's hand is suddenly out and gesturing.
Happy Birthday, Dear Hogan - S4-E26
Plot hole: In the cinema, Hogan and his female underground contact avoid attention from a passing plain clothes policeman by kissing. This is wrong for three reasons. Firstly, 3rd Reich Germany wasn't so liberal that open kissing in the cinema would have passed as normal, it would probably rather have been viewed as libertine and offensive. Secondly, the scene takes place with a speech of Hitler as the background, which can hardly be viewed as romantic, and thirdly, this is even more true for the Gestapo, who was tasked with ratting out political dissent. To a Gestapo officer, ignoring the Führer's speech and kissing instead would make them stand out doubly.
Factual error: Every episode and season there is "snow" on the ground even if it is warm.
Plot hole: Hogan's men steal the motor from the silent plane. When Klink and Burkhalter inspect the plane, Burkhalter doesn't notice the engine missing. Later Klink doesn't notice the fact that it has been put back. This is totally impossible for two reasons: Firstly, if a propeller airplane misses its motor, there is no place to mount the propeller. Secondly, when we get to see the whole plane, it becomes obvious that it has an open engine cowling which leaves the motor exposed to be cooled by the airstream. The propeller issue aside, if there is enough light to see the hand in front of your eyes, it is impossible to miss either the presence or the absence of an engine inside that kind of cowling. Add to this the fact that both Klink and Burkhalter are Luftwaffe (Air Force) officers and therefore by trade have some experience with airplanes, the whole thing becomes even more ridiculous.
Continuity mistake: As Schultz is telling Hogan that he's a family man, the shot ends with Hogan starting to turn his head to the left. The next shot shows Hogan looking straight at Schultz, then turning his head. (00:15:25)
Klink vs. the Gonculator - S4-E2
Factual error: They would never use their real names and whereabouts when talking on the radio.
Factual error: When the farmer sticks his pitchfork into the haystack, a scream is heard, but then everybody emerges unscathed. Wounds from pitchforks aren't like sitting on a brass tack - even a quick jab usually earns you a trip to the surgeon (I've seen such wounds), a vigorous stab like the one in the scene would go through limbs and could easily kill a man. There's no way anybody would walk away from such a hit.
The Great Impersonation - S1-E21
Factual error: When the three captured heroes stand before the Gestapo officer, he sweeps three sets of US identification tags into his hand. The names and uniforms suggest that the three captured personnel are from three different armies. Identification tags differ greatly between armies, all wearing US-style with their usual uniforms they would be worse off than wearing none at all. The Geneva convention would allow for them to be shot on the spot as spies under these circumstances since they initiated combat (blew something up) wearing false uniforms. (00:03:20)
Continuity mistake: When Hogan drinks Klink's wine, he picks up the glass with his right hand and his left arm is behind him. A second later, Hogan's left hand is in front of his chest.
Man's Best Friend Is Not His Dog - S4-E6
Continuity mistake: Hogan's arms change position when holding the dog. First, his left is under the dog, and after the angle change, his right is under the dog.
Sergeant Schultz Meets Mata Hari - S3-E4
Other mistake: As the lady Gestapo spy comes into the beer hall, Schultz not only has a matchbook in hand, but keeps looking at the action between the bartender and the lady, waiting for his entrance cue.
Continuity mistake: When Kinch raises the binoculars to look at The Tower, the neck strap is crossed in an "X" on his chest. When he puts them down, the strap is straightened.
Movies Are Your Best Escape - S1-E8
Continuity mistake: When Schultz herds the men into the barracks, Hogan and Le Beau are about three feet apart. A second later, they are only about a foot apart.
Continuity mistake: At the end, Hogan has the note from Nimrod in his right hand. When the shot changes, it's in his left hand.
Will the Real Colonel Klink Please Stand Up Against the Wall? - S4-E13
Continuity mistake: In Klink's quarters, Schultz stops Hogan from disturbing Klink. When he does, Schultz's arm is across his chest. When the angle changes, his arm is at his side.
Continuity mistake: The trick ring Morrison has is on his right hand at the hotel, missing in front of the hotel, and reappears in front of German HQ.
The Battle of Stalag 13 - S2-E5
Continuity mistake: As Hogan leaves Klink to go to his barracks, there is a distinct lighting difference on the porch where Klink is. The area between the supports of the porch roof is lighter in color than to Klink's left, also the shadows of the trusses are at a different slant than the area to the right of the screen. And there are extra shadows of the light and the support to Klink's left.
How to Cook a German Goose by Radar - S1-E24
Revealing mistake: When the boys set the trash can on fire in front of Klink's office, there is a problem with the trash. While the rest of the waste paper burns down there is one piece hanging over the top edge that doesn't burn, even being in the midst of the flames on that side.
That's No Lady, That's My Spy - S6-E17
Revealing mistake: When the men are in ranks for roll call, it's snowing heavily. Given the pitch of the barracks' roofs, there shouldn't be any snow sticking. Therefore, if looked at closely, it can be seen that the "snow" on the roofs is painted in place.
Answer: It's a comedy, not a documentary.
stiiggy
Perhaps it was counterfeit. There are numerous episodes where they deal in counterfeit monies.