Plain English Meaning

The second radio used for talking on the aviation airwaves. It works the same as the first one and lets the pilot have a second frequency ready to use.

Full Definition

COM2 is the second of two VHF communication radios installed in an aircraft, used for voice communication with air traffic control, flight service stations, and other ground or airborne stations. It operates in the same VHF aviation band as COM1 (118.000–136.975 MHz) and provides a secondary, independently tunable radio so the pilot can monitor or transmit on a different frequency without retuning the primary radio.