I work in Scottsdale and the airport is nearby. Every once in a while, maybe once or twice a week, some Apaches come down from a repair station up north on an exercise. I can feel them before I see them. The hair rises on my arms and everybody wonders what is going on with me. I know a military power rotor when I (don't hear) feel one. I feel like I am having a Quickening as in the Highlander. Hueys too and dear to my heart, the CH-3 Jolly Green.
Other civvie stuff sounds like an eggbeater. There is something about the whump of those rotors......I can feel it right down to my shit pincer.