Definition 1 of 2
Definition
Directives issued by air traffic controllers requiring a pilot to take specific actions, such as a heading, altitude, route, speed, or clearance to taxi, take off, or land. Compliance is mandatory unless the pilot declares an emergency or determines that following the instruction would compromise safety, in which case the pilot must advise ATC.
Plain English
Orders from air traffic controllers telling a pilot what to do — where to go, how high to fly, when to turn, or when to take off or land. Pilots must follow them unless safety requires otherwise.
Context Anchor
You hear ATC instructions during radio communication with controllers while taxiing, taking off, flying in controlled airspace, approaching an airport, or landing.
Derivation
Instruction comes from a Latin word meaning to arrange, prepare, or teach. In aviation, the meaning is narrower: it is a direction from a controller that tells the pilot what action to take.
Why Pilots Care
Following them keeps aircraft safely separated and prevents airspace violations.
Intuition Check
Do not treat an ATC instruction as a suggestion or casual advice. In this context, it is a controller’s direction to take a specific action unless you cannot safely comply.
Example Sentence 1
After takeoff, the pilot followed the ATC instruction to climb to 3,000 feet and turn left to a heading of 270.
Example Sentence 2
After landing, the pilot followed ATC instructions to taxi to the ramp via Alpha and Bravo.