Other mistake: In the opening credits, the copyright year is shown as MCMXLVII (Roman numerals for 1947), when it should be MCMLXVII (1967).
Other mistake: When Professor Potts bought Chitty from the Junkman and brings the car into the garage, the body of the car is charred or damaged somehow from the crash and fire. But the leather seats, dashboard and wooden steering wheel are completely unharmed.
Other mistake: The fight at the end is unintentionally quite funny for the lack of enthusiasm shown by the extras playing the Burpers. They engage the British soldiers with some half-hearted fighting that's little more than jostling, and when they disengage the fight supposedly in fear and panic at seeing the "Men in Skirts" reveal themselves, most of them are quite slow and calm as they try and get through the narrow gate to escape.
Other mistake: In the opening scene, where Henry Fonda is standing on the deck of the carrier, he is looking at his watch and he says "Zero Nine Hundred" If you look closely, the sweep second hand on the watch never moves from 4:00.