Goofs

Sgt. Schultz' serial number changes in every episode in which he announces it.

In numerous episodes, when it is supposedly winter with patches of snow on the ground, you can see leaves still on the trees and green grass on the ground in the background.

In "The Scientist", Carter states that he can't teach LeBeau any chemistry because he ran a drugstore, not a chemist's shop. But in the earlier episode "German Bridge Is Falling Down", he knew how to make explosive chlorine gas out of ammonia and bleach, and in the later episode "Hogan Springs", he mixed up a convincing batch of "mineral water" with no difficulty.

In the series' 18th episode ("The Gold Rush" 1966), Hogan and the gang make gold bricks into the steps leading into Commandant Klink's headquarters (disguised as regular masonry bricks). In the remaining 150 episodes, those same steps have reverted back to the wooden ones seen prior to that.

When the guards open the dog run to let them out, the gate swings outward. When the "heroes" open the gate it swings inward.

The Gestapo did not wear black uniforms as seen in Hogan's Heroes. While it was certainly a nice touch of artistic license to differentiate the more sinister Gestapo like Major Hochstetter from the relatively benign Luftwaffe guards, this type of black uniform was a ceremonial uniform seen mostly on the guards at important buildings or at state functions. The appearances by the Gestapo in plain clothes and a Nazi party tie pin are closer to the truth (as seen on Raiders of the Lost Ark (1981), for example).

Major Hochstetter's collar insignia is that of a Standartenführer or the U.S. Army equivalent is a full colonel.

Throughout the series, interior doors always have round door knobs. American doors usually have round door knobs. German doors almost always have a door handle (die Türklinke) rather than a round door knob.

Throughout the series, all vehicles have Army license plates (WH, i. e. "Wehrmacht/Heer"). The vehicles from Stalag 13 should have Air Force license plates (WL, i. e. "Wehrmacht/Luftwaffe"), as it technically is an Air Force unit.

Hogan and the other Heroes would never have been stationed together. There was a separate POW camp for officers.

During evening scenes, you can hear crickets chirping. They would not exist during a typical German winter.

In many episodes something is dropped to the heroes by parachute. In almost every case when "something" leaves the plane it is obvious that it is a person since a pair of legs is clearly visible, yet usually when it comes down it is a box or some other container.

Sometimes you see the warning "Gebrauch keine Haken" on boxes in the background. This is a literal translation of the English "Do not use hooks" and would never be written in that form on a German box. Correctly it would have to be "Keine Haken verwenden".

Sgt. Carter usually wore gloves, but many times he didn't, and Larry Hovis' wedding ring is visible even though Carter is single.

In several episodes (possibly using the same footage) a guard opens the kennel to release the guard dogs, but the kennel appears to be a very flimsy prop not strong enough to hold aggressive dogs.

Taking into account the losses of aircraft both British and American during the war, it is unlikely that a solo plane could fly from England (and return again) to deliver items to the camp deep in Germany territory anytime the heroes needed something.

Whenever a roll call takes place for the prisoners at Stalag 13, it seems that Hogan's barracks is the only one involved.

Since the series mostly takes place during winter, footprints would often be seen in the snow when sneaking out of camp.

In one scene taking place in a German laboratory, a periodic table of elements is hanging on a wall. It shows all the 103 elements known to science in the 1960s, but during the war, fewer than 92 elements were known: the rest were created by nuclear science, including several instrumental in the top-secret Manhattan Project.

On numerous occasions Eva Braun, Hitler's mistress, is mentioned either by Hogan's men or the Germans. Braun's association with Hitler was a closely guarded secret only known to Hitler's inner circle, and whose existence wasn't revealed until after the war.

The center top ribbon on Colonel Hogan's dress uniform is the Air Force Distinguished Service Medal, an award that was created by the Air Force after World War II.

Although the series takes place during World War II, the women wear the clothing and hairstyles of the 1960's.

Several episodes reference baking a German Chocolate Cake, which was first baked in Dallas, Texas in 1957, and named after Samuel German, who developed a type of dark baking chocolate for the Baker's Chocolate Company. The brand name of the product, Baker's German's Sweet Chocolate, was named in his honor. This recipe used the baking chocolate introduced 105 years prior and became quite popular. World War II ended in 1945 - 12 years before it was first baked.

In many instances, production lights are seen reflecting off of Klink's monocle. Based on where lighting is located, almost any reflection off of the monocle would be a production light. In some cases, both the light bulb and the reflector dish can be seen.

The palms of Los Angeles are clearly visible in the treeline around Stalag 13 in some episodes. Date palms can be seen in outdoor scenes in 'The Well' for example. Very few palms grow outdoors in Germany, if any. Helps to use HD TV, I never would have seen this on the old B&W analog set.

Hogan is occasionally called away to London and even Washington D.C. for instructions, and frequently goes to German towns as well as to Berlin on missions disguised as a German officer. Yet somehow he is never missed on the daily roll calls that were common practice in German POW camps.

It seems that no prisoner, including Hogan, speaks German. If their overall mission really was as the main plot says, at least one, if not all, of the prisoners stationed there would speak German. The closest that there is in the series is speaking English with a German accent, and having Schultz translate the German to English.

During many an episode, on the right breast of Schultz's tunic, the eagle and swastika patch is backwards. The eagle should be pointing to Schultz's left, facing his heart.