We tend to use the term Uncontrolled Airport to describe airports without control towers or airports with non-operating control towers.

The current FAA circular with the regulatory, recommended operations and communication procedures for uncontrolled airports is AC 90-66B, "Non-Towered Airport Flight Operations" dated March 13, 2018. It incorporates the latest best practices with flight safety as the primary objective.

The circular covers a lot of great information including flight patterns and communications for gliders, balloons, parachute jumping and more. You may find that some of this...