An early UAV: DASH

The Drone Anti-Submarine Helicopter was an early UAV and was deployed in large number throughout the US fleet starting in the 1960s. I served in destroyers with DASH hangers, but never got to see one in action. There were lots of rumors about how hard they were to control and how they would just occasionally just decide to fly over the horizon, usually with a destroyer madly chasing after trying to regain radio contact.

This website has a lot of photos and some interesting stories about this precursor to the modern UAVs. Here's photo from that site of a DASH in the air.