Definition
The primary VHF transceiver used for two-way voice communication between the aircraft and ground stations such as ATC, flight service, and other aircraft. In an aircraft equipped with two or more communication radios, Communication Radio #1 (often labeled COM 1) is the designated primary unit and is typically wired to receive backup electrical power from the standby battery if the main electrical system fails.
Plain English
The main radio the pilot uses to talk to controllers and other aircraft. When an airplane has more than one radio, this is the one numbered as the first, and it is usually the one kept working on the backup battery if the main electrical system quits.
Context Anchor
Seen on avionics panels, electrical load lists, standby battery procedures, and checklists as the first or primary communication radio.
Derivation
Communication comes from a Latin word meaning “to share” or “make common.” Radio comes from the idea of sending signals through radiated energy. Together, the term points to a radio that lets the pilot share spoken information with others outside the aircraft.
Why Pilots Care
Allows continued two-way communication with ATC and other aircraft during total electrical failure, supporting safe emergency handling and landing.
Intuition Check
“#1” does not mean the radio is the best radio. It means the first or primary communication radio installed and labeled in that aircraft.
Example Sentence 1
After the alternator failed, the pilot switched to standby battery power and continued talking to approach control on Communication Radio #1.
Example Sentence 2
Communication Radio #1 stayed available on the backup battery while Comm 2 and most other radios shut down.