When in a hollywood movies warplanes dive down, after being shot for instance, they 9 out of 10 make this distinctive noise of a Stuka Dive bomber plummeting to earth. We know that the Stuka bomber made this scary sound because the nazis put sirenes on them for the specific purpose of scaring the living daylights out of people on the ground. But does a normal airplane, going down with a considerable speed, make noise at all? A glider plane doesn't I reckon. So why would a normal plane with its motor still running?
