Other mistake: As Schultz goes to stick a pin in the map, he supposedly hits his finger. But if you look closely, he actually stuck it in the map at the very tip of his finger. This is clear because he didn't move the pin at all.
Continuity mistake: In this episode, the Notausgang (Emergency Exit) sign is over the door. In other episodes, it is on the door.
Continuity mistake: The bridge Buckles and the boys put TNT on is significantly different than the one blown up. Also, the one destroyed is a re-used shot of a bridge being blown up.
Other mistake: As Buckles holds up the scale model of the Bismarck, the diagonal cut where it's supposed to "break" is visible.
Continuity mistake: The apple that Freddie is eating at the end goes from green to red.
Continuity mistake: When Hogan is by the truck, Newkirk responds to his question about packages. Crittendon has his swagger stick under his arm, then it's suddenly in front if him in his hands.
Is There a Doctor in the House? - S3-E18
Other mistake: As Carter gets ready to clean out the stove, Newkirk closes his eyes and winces just before the bellows Carter has blows.
An Evening of Generals - S3-E13
Continuity mistake: In Klink's office, the lower corner of the poster Hogan holds up alternates between being over the right side of his chest, to being tucked under, and back.
An Evening of Generals - S3-E13
Continuity mistake: In the barracks, after Hogan asks Newkirk about volunteering, the coffee cup Newkirk has is held with his left hand fingers in the handle. After the angle cut, the cup is in his hand with the handle toward the camera.
Clearance Sale at the Black Market - S4-E1
Revealing mistake: After Kiegel shoots out the bulb the light takes a couple of extra seconds to fade out.
Visible crew/equipment: As Klink's car pulls up, and Klink comes around the front of it, the shadow of the camera is visible.
Nights in Shining Armor - S3-E8
Other mistake: When Hogan shoots the vest, it stays still for a couple of seconds then swings in a way that is not normal.
The Safecracker Suite - S1-E27
Continuity mistake: After saying "I hate to be a killjoy", Newkirk has his fork up and pointed towards Kinchloe. A second later, it's pointed down.
Factual error: Numerous times throughout the series, there are palm trees seen in different shots. Stalag 13 was supposed to be just on the outskirts of Hammelburg. The only place anywhere near there that could support palms was the area around the Bodensee (Lake Constance), so therefore the palms seen are a big mistake.
Anchors Aweigh, Men of Stalag 13 - S1-E16
Audio problem: As the last German soldier before Hogan goes up the ramp, Le Beau is heard saying "schnell, schnell!" (fast, fast). As he says it, his mouth doesn't move.
Anchors Aweigh, Men of Stalag 13 - S1-E16
Continuity mistake: After saying that Michaels disappeared, truck and all, Klink brings his hands together, and interlaces his fingers. A second later, the fingers interlace again.
Anchors Aweigh, Men of Stalag 13 - S1-E16
Continuity mistake: In Klink's office, as Hogan tries to make a fast exit, Klink calls him back with "I'm not finished with you yet." As he does, his hands are clasped in front of him, then a second later, they are down on the desk.
Continuity mistake: The emblem on the left side of Schultz's helmet is mostly gone. Later when apprehending Stoffel, the emblem is complete.
Visible crew/equipment: As Hogan and Le Beau crawl through the car and shut the door, the camera rig, equipment, and cameraman are reflected in the window.
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. The term "nimrod" is also slang for a nerdy, doofus type of person, though it's unclear why that was his code name.
raywest ★
"Nimrod" is originally a king and hero mentioned in the Tanach and taken into the Bible and the Koran. His name is often used in the sense of "stalker," "hunter," and sometimes figuratively as "womanizer" as in "hunter of women." I've never seen it used to denote a nerdy person, and although I cannot disprove that connotation, I think given his role, the traditional meaning is more likely the intended one.
Doc ★
It's widespread enough that Wikipedia has an entire section on it: https://en.wikipedia.org/wiki/Nimrod#In_popular_culture