National Air and Space Museum (NASM) in Washington, DC. Explore amazing variety of planes and rockets as well as crafts of all sizes and shapes from a variety of different eras as well as places. It also aeronautic research center.
Close up skull would be a good tattoo, with something hidden in the eye. city scape, comic book scenario/villain, doctor who reference etc. Thigh/side/leg/upper right arm (ribs maybe? but PAINFUL)