Read-back is defined as a procedure whereby the receiving station repeats a received message or an appropriate part thereof back to the transmitting station so as to obtain confirmation of correct reception.
The flight crew shall read back to the air traffic controller safety-related parts of ATC clearances and instructions which are transmitted by voice (and by text for IVAO).
Strict adherence to read-back procedures ensures not only that the clearance has been received correctly, but also that the clearance was transmitted as intended.
The stringency of the read-back requirement is directly related to the possible seriousness of a misunderstanding in the transmission and receipt of ATC clearances and instructions.
Read-back requirements have been introduced in the interest of flight safety.
The following shall always be read back:
- ATC route clearances
- clearances and instructions to enter, land on, take off from, hold short of, cross and backtrack on any runway
- runway-in-use, altimeter settings, SSR codes, level instructions, heading and speed instructions
- transition level
ATC advice, suggestions and requests shall not be read back. Unless requested by an ATC unit, voice read back of a data link communication message is not required.
ATC shall listen to the read back to ascertain that the clearance or instruction has been correctly acknowledged by the flight crew. ATC shall identify and correct any error made during read back of a clearance or instruction.
Examples of read back:
If an aircraft read-back of a clearance or instruction is incorrect, the controller shall transmit the word "NEGATIVE I SAY AGAIN" followed by the correct version.
Examples of read back: