Definition
An aviation term describing an aircraft operating without two-way radio communication capability, either because no radio is installed or because the radio has failed in flight. NORDO aircraft must follow specific lost communication procedures, including the use of light gun signals from the control tower when operating in or near controlled airspace.
Plain English
An aircraft that cannot talk to air traffic control by radio, either because it has no radio or its radio has stopped working.
Context Anchor
Seen in lost communication procedures, towered airport operations, and situations where a pilot may need to rely on visual signals instead of radio calls.
Derivation
A shortening of "No Radio." The term came into common use in the early decades of controlled airspace, when many small aircraft genuinely had no radio installed and a quick label was needed for them in tower and ATC communications.
Why Pilots Care
A NORDO aircraft must follow specific lost-comm procedures, including squawking 7600, to maintain separation and reach its destination safely.
Intuition Check
NORDO does not always mean the airplane is unsafe or has no electrical power. It means usable radio communication is not available.
Example Sentence 1
After the avionics failure, the pilot squawked 7600 and continued to the destination as a NORDO arrival, watching the tower for light gun signals.
Example Sentence 2
If your radio fails, declare yourself NORDO and follow the published lost-communication route.