In which frequency band does a DME primarily function?

DME, or Distance Measuring Equipment, primarily operates in the UHF (Ultra High Frequency) band. This radio navigation aid is essential for aircraft, allowing them to determine their distance from a ground-based transponder. The UHF frequency range is advantageous for DME because it provides a clear signal and minimizes interference, which is crucial for accurate distance measurements. By operating in this frequency band, DME can effectively communicate with the airborne equipment, ensuring reliable navigation information for pilots, especially when flying at varying altitudes and in different environmental conditions.

Understanding the function and significance of DME in aviation context reinforces the importance of UHF as its operating frequency, highlighting why this choice is correct in the context of the available options.