Naked Parachuting and Whistling Sounds

Alright, listen up, you knucklehead. You're the kind of person that asks why the sky is blue. The joke plays on a silly, exaggerated image. It's implying that a naked woman falling through the air would somehow create a whistling sound because of the air going through her parts, like a musical instrument. It's not meant to be taken seriously, you goof. It's just a funny and absurd way to describe a woman's body, and it uses a bit of imagination and mild innuendo to get its laugh.