This is an excellent thought experiment! I was lucky to fly quite a lot with my mother and father (a WW2 fighter pilot from whom I caught the aviation but) although it wasn’t always easy to be a son and pilot in command or copilot at the same time… I’d find it interesting to fly with Leonardo da Vinci. Even if I’d probably find it hard to converse with him I’d love to show him how his flying dreams were developed and would find it very interesting to see his grasp of a technology a couple of centuries beyond his. (I suppose he’d understand a lot pretty quickly and say something like “I should have thought of this”, something probably true for most of the early aviators as well whose main hindrance was a lack of suitable technology to build their designs. I’d be humbled to be offered even a right seat next to a lot of other aviation greats.