What is the main purpose of Standard Terminal Arrival Routes (STARs)?

The main purpose of Standard Terminal Arrival Routes (STARs) is to simplify the transition of aircraft from the en route phase of flight to the approach phase for landing at an airport. By providing designated routing, STARs help streamline communication and coordination between pilots and air traffic control (ATC) during busy terminal operations. This efficiency improves the flow of traffic in and out of busy airspaces, facilitating more predictable and organized arrivals, ultimately enhancing safety and efficiency in the terminal airspace.

While there are aspects related to altitude requirements, controlled airspace, and training flights, these are not the primary focus of STARs. The design of STARs encompasses procedures that facilitate orderly arrivals rather than setting minimum altitudes, managing VFR traffic, or specifically addressing IFR training situations.