The "meatball" https://en.wikipedia.org/wiki/Optical_landing_system https://en.wikipedia.org/wiki/Optical_landing_system The system described is for aircraft c

The "meatball" https://en.wikipedia.org/wiki/Optical_landing_system https://en.wikipedia.org/wiki/Optical_landing_system The system described is for aircraft carriers. I know about it because I maintained a smaller version on a fast frigate in the seventies. It was slaved to the ship's gyrocompass, which provided a stable horizontal reference. (Besides navigation, the gyrocompass also provided that stable reference to the ship's gun.)