Those Magnificent Men in Their Flying Machines (1965)

Other mistake: The Japanese plane and the German plane are actually the same aircraft, a British Design called an "Eardly Billing". The "Japanese" version is re-dressed with canvas partitions between the wings, painted dragons, etc, the "German" has no canvas and German eagles, but they are the same machine.

Other mistake: As the planes go over Dover you get a very nice view of the modern harbour complete with cross Channel ferries and oil tanker.