Standard Terminal Arrival Routes (STARs)
A Standard Terminal Arrival Routes, STAR, is a flight route defined and published by the air navigation service provider that usually covers the phase of a flight that lies between the last point of the route filled in the flight plan and the first point of the approach to the airport, normally the initial approach fix (IAF). Hence, a STAR connects the enroute phase with the approach phase of the flight.
A typical STAR consists of a set of starting points, called Transitions, and a description of routes (typically via VORs and intersections) from each of these transitions to a point near a destination airport, upon reaching which the aircraft can join an instrument approach (IAP) or be vectored for a final approach by terminal air traffic control.
STARs can be used if radar services are not available. However, if radar services are available, STARs won’t be used. If you wish to use a STAR, you can ask the controller if he will allow you to use a STAR.