Which NAVAID uses L/MF or UHF radio beacons to transmit non-directional signals that allow pilots to determine their bearing to or from the beacon?

The non-directional beacon, or NDB, uses L/MF (Low/Medium Frequency) or UHF (Ultra High Frequency) radio beacons to transmit non-directional signals. This capability allows pilots to determine their bearing to or from the beacon. NDBs transmit a continuous radio signal in all directions, which can be received by aircraft equipped with an automatic direction finder (ADF). The ADF triangulates the beacon’s position, enabling pilots to navigate by determining the direction from the aircraft to the beacon.

In contrast, other options do not function in the same way. The VOR (VHF Omnidirectional Range) provides directional information and requires a different type of receiver; it transmits a signal that allows the aircraft to ascertain its bearing from the station. The ILS (Instrument Landing System) is more specialized, designed primarily for approach and landing, utilizing both localizer and glide slope signals, rather than providing a general navigation beacon function. GPS (Global Positioning System) utilizes satellite signals for navigation rather than ground-based beacons.

By understanding the unique functionality of the NDB, pilots can effectively use this navigational aid for positioning and course guidance.