Factual error: When Clark speaks to Jor-El for the first time in the Fortress, Jor-El says "I will have been dead for many thousands of your years..." Fine in theory - Baby Kal-El travelled to Earth at above light speed so time passed differently for him. However, as such, wouldn't Jor-El have seen Earth as it was thousands of years ago? Which also makes there a problem with all the things Kal-El was taught during his voyage to Earth, as Jor-El references Einstein by name, for instance, and he would not have existed at the point when Jor-El sent him to Earth.
Factual error: The "Cable Junction" in the movie is a transformer junction station built on a rock pile however when you look at it there is no algae or barnacles anywhere on the rocks. This is impossible because algae and barnacles thrive on rocks in sea water.
Factual error: The Force 10 finally manage to escape of the German ammunition depot by train. However, when the train leaves the tunnel and the men jump off the train the engine is a modern red and white electric locomotive. Only one problem: Electric trains did not exist in Yugoslavia until 10 years later. The engine is a mid-60's Swedish type RC.
Factual error: During the fire scene at night, the water truck has "Vasser" printed on the side. Water in German is spelled "Wasser."
Factual error: At the end of the fight between Pai Chang Tien (the Old Man) and Shu Chin (the fan-wielder), Pai catches his opponent with his pipe on the larynx and strangles him to death. In his death-throes Shu Chin groans until he dies; but with a piece of wood pressing down on his windpipe, he realistically wouldn't be able to make such a pronounced sound. (01:19:10)
Factual error: When Rita is in the doctor's surgery for her prenatal visit, the chest X-ray in the background is upside down.
Factual error: When the bad guys collect the $100 million in cash from the vault, it's been laid out in just 2 suitcases. According to US government specifications, that much cash (it is mentioned in the movie that it is in $100 bills) would be a single pile nearly 50 feet high (about 10 times what is shown) and 1,000kg - a full ton of weight.