Probably everyone here knows that fighter planes in WWI eventually used an interrupter system to fire bullets through the arc of the propeller without shredding the prop in the process. I hadn't known exactly how it was done, though, and found this article (written on a site that usually discusses projects in embedded electronics and mechanisms like you'd find in robots) to be interesting:
https://hackaday.com/2018/04/25/firing-bullets-through-propellers/
https://hackaday.com/2018/04/25/firing-bullets-through-propellers/