What type of navigational aid is a VOR?

A VOR, or VHF Omnidirectional Range, is a type of ground-based navigational aid that operates on Very High Frequency (VHF) radio signals. It provides pilots with azimuth information, allowing them to determine their heading relative to the station. The system transmits a 360-degree signal that a receiving aircraft can interpret to ascertain its direction from the station.

This ground-based characteristic is essential for navigation, particularly for flight operations in controlled airspace and during instrument flight rules (IFR) conditions. The fact that it operates within the VHF band emphasizes its role in providing reliable and precise guidance for pilots, distinguishing it from other navigational aids such as satellite-based systems, which operate on different principles and infrastructure.

Other options such as satellite-based navigational aids or portable devices do not accurately describe the fundamental nature of a VOR, as it specifically relies on ground-based equipment and standardized signal transmission that is consistent across aviational practices.