My Dad watched this happen years ago at a lake:
Older, 1970s time frame, I/O day cruiser (they usually had pretty big cockpits), became driverless, and was making large circles, at a lake, slowly being pushed toward a crowded beach by breeze. As a couple people realized what was happening, time was running out to do something about it, and the boat was going to hit the swimmers if it did not hit this particular dock first. Turns out, a 16 year old kid attempted and succeeded in a running leap into the boat, as it passed the end of this dock, got the drivers seat, and brought the boat back in safely. The kid was heralded as a local hero.