Special Notice -- NAT ATS Message Format

The following is submitted in an effort to standardize ATS message formats for air/ground communications in the North Atlantic (NAT) Region:

1. General
   1. All NAT air−ground messages are categorized under one of the following headings (excluding emergency messages):
      1. Position Request.
      2. Request Clearance.
      3. Revised Estimate.
      4. Miscellaneous Message.
   2. In order to enable ground stations to process messages in the shortest possible time, pilots should observe the following rules:
      1. Use the correct type of message applicable to the data transmitted.
      2. State the message type on the contact call to the ground station or at the start of the message.
      3. Adhere strictly to the sequence of information for the type of message.
      4. All times in each of the messages should be expressed in hours and minutes.
2. Description of ATS Message Types. Aircraft should transmit air−ground messages using standard RTF phraseology in accordance with the following:
   1. POSITION. To be used for routine position reportsContent and Data Sequence
      1. “POSITION.”
      2. Flight identification.
      3. Present Position.
      4. Time over present position (hours and minutes).
      5. Present flight level.
      6. Next on assigned route.
      7. Estimated time for next position (hours and minutes).
      8. Next subsequent position.
      9. Any further information; e.g., MET data or Company message.

         EXAMPLE−
         “Position, SWISSAIR 100, 56N 010W 1235, flight level 330, estimating 56N 020W 1310, next 56N 030W”

          

   2. REQUEST CLEARANCE
      1. To be used, in conjunction with a routine position report, to request a change of mach number, flight level, or route and to request westbound oceanic clearance prior to entering Reykjavik, Santa Maria or Shanwick CTAs.Content and Data Sequence
         1. “REQUEST CLEARANCE.”
         2. Flight identification.
         3. Present or last reported position.
         4. Time over present or last reported position (hours and minutes).
         5. Present flight level.
         6. Next position on assigned route or oceanic entry point.
         7. Estimate for next position or oceanic entry point.
         8. Next subsequent position,
         9. Requested Mach number, flight level or route.
         10. Further information or clarifying remarks.

             EXAMPLE−
             “Request clearance, TWA 801, 56N 020W 1245, flight level 330, estimating 56N 030W 1320, next 56N 040W, requesting flight level 350”

              

      2. To be used to request a change in Mach number, flight level, or route when a position report message is not appropriate.Content and Data Sequence
         1. “REQUEST CLEARANCE.”
         2. Flight identification.
         3. Requested Mach number, flight level or route.
         4. Further information or clarifying remarks.

            EXAMPLE−
            “Request clearance, BAW 212, requesting flight level 370”

             

   3. REVISED ESTIMATE. To be used to update estimate for next position.Content and Data Sequence
      1. “Revised Estimate.”
      2. Flight Identification.
      3. Next position on route.
      4. Revised estimate for next position (hours and minutes).
      5. Further information.

         EXAMPLE−
         “Revised estimate, WDA 523, 57N 040W 0325”

   4. MISCELLANEOUS. To be used to pass information or make a request in plain language that does not conform with the content of other message formats. No message designator is required as this will be inserted by the ground station.Content and Data Sequence
      1. Flight identification.
      2. General information or request in plain language and format free.

(ZNY, Updated 5/24/2018)