Which system is used to transmit flight plan messages between ATS units?

Which system is used to transmit flight plan messages between ATS units?

• A. AFTN
• B. VHF Data Link
• C. ACARS
• D. HF Radio

Answer: (A)

The system used to transmit flight plan messages between ATS units is the Aeronautical Fixed Telecommunication Network. AFTN is a worldwide fixed network that carries text messages between Air Traffic Service units using standardized formats (such as flight plans and amendments) and fixed addressing. Messages are stored and forwarded through intermediate nodes, ensuring reliable delivery to the correct ATS unit across regions and countries. This dedicated channel for inter-ATS messaging keeps flight plan information separate from voice or ground-to-air data links. Other options serve different purposes: VHF Data Link is for data exchange between aircraft and controllers (CPDLC), ACARS handles various airline operational messages between aircraft and ground systems, and HF Radio is used for long-range voice or basic data links, not the standard method for inter-ATS flight plan transmission.

The system used to transmit flight plan messages between ATS units is the Aeronautical Fixed Telecommunication Network. AFTN is a worldwide fixed network that carries text messages between Air Traffic Service units using standardized formats (such as flight plans and amendments) and fixed addressing. Messages are stored and forwarded through intermediate nodes, ensuring reliable delivery to the correct ATS unit across regions and countries. This dedicated channel for inter-ATS messaging keeps flight plan information separate from voice or ground-to-air data links.

Other options serve different purposes: VHF Data Link is for data exchange between aircraft and controllers (CPDLC), ACARS handles various airline operational messages between aircraft and ground systems, and HF Radio is used for long-range voice or basic data links, not the standard method for inter-ATS flight plan transmission.