Plain English Meaning

Having two working VHF radios in the aircraft so the pilot can listen to or talk on two frequencies at once, instead of just one.

Full Definition

An aircraft radio configuration in which two VHF communication radios are installed and operable, allowing the flight crew to monitor or transmit on two separate frequencies at the same time. For PRM (Precision Runway Monitor) approaches, dual VHF communications capability is required so the crew can stay on the tower frequency while simultaneously monitoring the PRM monitor controller's override frequency.