[kach22i]

Interesting image selection given the topic.

Why did World War 2 bombs made whistling sound while they fell ?
https://mechstuff.com/why-did-air-bombs-made-whistling-sound-during-world-war-2/

In the above audio clip, the pitch is decreasing ⇒ source moving farther from listener ⇒ therefore pilot’s perspective.
Reverse the audio clip, pitch will increase ⇒ source approaching towards listener ⇒ and this is what the bomb would sound like to a person on the ground.

Now don’t ask me why sound producers decided to use the sound effect heard from a pilot’s perspective.