Factual error: In the warehouse scene, the lights and other metal objects are affected by the box's magnetic field. Yet the soldiers easily lift the box into a metal truck to load it and slide it forward. If the box's magnetic field was as strong as suggested, it would have dragged the soldiers forward as it was magnetically attracted to the truck, and it would have taken much more effort for them to slide it onto the truck bed once it was stuck there.
Factual error: The movie supposedly is set in 1957, yet Mutt's motorcycle is based on a 2000 or newer Harley Davidson softail, showing the modern-day controls and Twin Cam motor, instead of the panhead motor that would have been the period-correct engine for 1957. It also has a front disc brake - you can see the master cylinder on the handlebars. Again, out-of-place on a 1957 bike.
Factual error: Indy and Mutt fly to Nazca, Peru. Nazca is only 4 hours away on bus from the capital Lima, yet the city they show on the movie is Cuzco, which is 24 hours away from Lima. Cuzco is on the east side of the country, Nazca is on the west coast right next to Lima. Also, back in 1957 only Lima had an airport, yet they show a Nazca airport that didn't exist.
Factual error: During the fight in the rocket engine testing facility, the countdown timer has electronic digital numerals. In 1957, the countdown timer would have had flipping numbers, which are mechanically changed as the timer counts down, or a nixie tube display. See films like Fail Safe and Goldfinger for examples of such clocks or timers. LED's weren't even invented until 1962.
Add timeKylie Suttor
Factual error: In the warehouse when Indy and the Soviets open the crate with the alien's body, all the overhead lights are pulled towards it. If the magnetic field was that strong, the lights also would have been pulled towards the box before it was opened. (Put a toy car on top of a table and pull it with a magnet from under the table to see the field in action).
Factual error: At the beginning of the movie where the convoy stops at the gate to the military base, the fence has "Razor Wire" on the top, not the period-correct barbed wire. Razor wire came into use in the late sixties by some industries, but the military did not use it until the eighties.
Factual error: In the bar fight scene, a voice yells out "get that greaser!" just before the fight breaks out. However, the term 'greaser' (used to describe a leather jacket wearing youth of the 1950's) was not used to describe this clothing style until later decades - at the time they were called "hoods".