Go Light on the Heavy Water - S1-E9
Continuity mistake: When the smoke bomb goes off, Klink has his monocle on. After the smoke really starts, his monocle is gone without being taken off.
Go Light on the Heavy Water - S1-E9
Other mistake: After the smoke bomb goes off in Klink's office, there is a shot from the outside where the boys get a blanket to catch Klink. If you look at the window of the office behind them, you can see the smoke coming out in an up and down pattern, suggesting the smoke to be coming from a rig controlled by an out-of-sight crew member.
Movies Are Your Best Escape - S1-E8
Visible crew/equipment: When the staff car is entering and coming to a stop in the compound, the reflection of the crew member, camera and lighting rig can be seen in the chrome of the radiator.
Go Light on the Heavy Water - S1-E9
Visible crew/equipment: When the staff car entering the compound stops, you can see a reflection of the crew member stopping the car, the light rig, and the camera in the chrome.
Other mistake: After the truck is stopped, Newkirk tosses a dart at the tyre in order to flatten it. Since the tyre hit was the rear tire, there should have been the track from the front tire, but wasn't. Also, a puny, hand-tossed dart couldn't have penetrated the thick construction of a heavy-duty truck tire, let alone flatten it in twenty seconds.
Other mistake: When stopping the truck and Schultz, the area directly behind Carter and LeBeau can be seen to be a matte painting. The reason is because where they are is completely covered in snow, but the open area is very little, and there is a huge snowdrift piled up at the wall.
Happy Birthday, Adolf - S1-E17
Visible crew/equipment: When spying on a gun emplacement, LeBeau is dressed as a little old lady. When putting on his shawl before going back, you can see the studio lighting reflected on the glasses he wears.
Anchors Aweigh, Men of Stalag 13 - S1-E16
Visible crew/equipment: When in Klink's office, Hogan gives Klink the bum's rush, convincing him that he's tired. After Klink sits, the camera pans around. As it does so, you can see the shadow of the camera rig.
Oil for the Lamps of Hogan - S1-E14
Other mistake: Anytime Hogan steals one of Klink's cigars from the back of the humidor, he takes the hinge pin out from the left of the box (camera's right). This time, he takes out the pin, got the cigar, and put the pin back in from just what looked like just left (camera's right) of center.
Happiness Is a Warm Sergeant - S1-E11
Continuity mistake: When accessing the tunnel entrance, usually the spot is in the middle of the side board that is tapped. Newkirk slaps the corner and post of the top bunk.
Top Hat, White Tie and Bomb Sights - S1-E10
Revealing mistake: When General Burkhalter has entered the camp and is stopped at the gate, the camera cuts to Hogan and the guys. Above the barracks, you can see the Desilu water tower. (00:15:30)
Top Hat, White Tie and Bomb Sights - S1-E10
Audio problem: When Schultz comes into Hogan's office with the pie plate, he starts talking about Klink. As Hogan puts his hand over Schultz's mouth to stop him talking, Schultz is cut off mid-word. The sound he made is heard there, and again at Klink's office, almost like an echo, when everything else said is heard in real time. (00:08:40)
I Look Better in Basic Black - S1-E28
Revealing mistake: When Hogan, Newkirk and Lebeau are dressed as the three women captured by the Gestapo, demand the truck be stopped, the wide shot shows that the truck is already stopped, and shaken to simulate it stopping.
The Informer - S1-E1
Continuity mistake: In this episode, the doghouse that disguises an entrance to the underground is flipped up on end, and the separate floor is flipped up in the opposite direction. In all of the following episodes, the doghouse, and the floor, are one piece.
The Informer - S1-E1
Continuity mistake: In this episode, Burkhalter holds the rank of Colonel, Carter is a Lieutenant. In subsequent episodes, Burkhalter is a General, and Carter is a Sergeant.
How to Cook a German Goose by Radar - S1-E24
Revealing mistake: Toward the end of the episode, a guard is watching Helga posing in a one piece bikini for Lebeau. As you look past him, you see only blue screen, no view of the surrounding property. Same when Hogan climbs up, you don't see the tops of buildings; you can tell it's on a soundstage.
How to Cook a German Goose by Radar - S1-E24
Revealing mistake: After Hogan and the boys decide to get rid of Tillman, they "accidentally" set fire to the trash can on the Kommandant's porch. To that end they load up a bunch of trash that's been soaked in gas. Then Hogan tosses a lit match in it. The fire starts at the bottom, but all of gas soaked stuff, and the match, were at the top.
Oil for the Lamps of Hogan - S1-E14
Continuity mistake: Toward the end, Klink removes his monocle while talking to Hogan about the oil. Through the next few cuts between them, the monocle is off. When Hogan goes to leave, there is a shot from behind Klink, and he doesn't move, yet the next closeup of Klink shows the monocle in place.
I Look Better in Basic Black - S1-E28
Revealing mistake: A very long fuse is laid down then lit by the boys to distract the guards. While it is burning, watch the fuse in the dirt - it is actually being pulled from offscreen to the right of the shot.
The 43rd, a Moving Story - S1-E23
Other mistake: When Hogan uses the water barrel periscope to spot Manor Kuhn, the first shot is from an impossible angle.
Answer: Nimrod's actual identity was never revealed in the series. It was only known that he was a British intelligence agent. Nimrod was not Colonel Klink. Hogan had only implied it was him as a ruse to get Klink returned as camp commandant, not wanting him replaced by someone more competent who would impede the Heroes war activities. (As another contributor previously posted, the term "nimrod" is slang for a nerdy, doofus type of person, though it's unclear why that was his code name).
raywest ★