In the past, in order for users to interact with datalink driven functions, such as obtaining winds, flight plan uploads or takeoff performance data, we have simulated the ACARS link in the background without bothering the pilot to actually establish the ACARS datalink prior to using these functions. Effective with the release of the PMDG 747-8, it is now necessary in the entire PMDG 747 product line to take the steps to activate the ACARS data link in order to receive these services.
Activating the data-link is simple and can be accomplished in two easy steps:
• Complete the ORIGIN, DEST and flight number fields on the RTE page of the FMS as you normally would during the course of preflight. It isn’t necessary to use an actual airline carrier code or flight number if you are operating outside of PMDG Global Flight Operations, so feel free to make one up as you like.
• On the center CDU, press the ACARS or DLNK line select key, then populate the ORIG STA, DEST STA with the ICAO codes of the origin and destination airports, the ETD and ETE fields with your estimated time of departure and estimated time enroute. Insert the two letter IATA code of the airline you fly.
You will notice that there are a few fields on this display that are surrounded by [braces] or squares . The [ ] or  is your indication that "this field is currently allowed to be modified." For example, you can modify the UTC Departure date on the page above during preflight, but once the flight has begun, this field is locked out and the [ ] will be removed.
• After completing the above data you need to press the DLNK CNCT in order for the login process to occur. Once logged in, you will hear a chime, and an accompanying EICAS message, and the prompt on the <PREFLIGHT page will also show *DLINK ACT.
• As soon as the Datalink is active on the RTE page you can press the Request Send and then the Request for the Route to be fetched
One topic that sometimes causes confusion, is understanding the difference between a "CO ROUTE" and a "REQUESTED" flight plan. To help you avoid confusion, it is helpful to think of it this way:
- CO ROUTE: This is a route stored in the memory database of your FMS unit onboard the aircraft. This was a popular function in the late 1980s and 90s, as it reduced the amount of time crews would spend hand-keying flight plans. Much like the real FMS, using this function will cause the FMS to check and see what flight plans you have stored in the /FLIGHTPLANS directory, and treat them as if they are native to it's own memory database for you to select.
- REQUEST: Flight plans that are brought in via a datalink request are coming from outside of the airplane. The advent of modern datalink technology has made this by far the most common and useful method to transmit a flight plan to the crew onboard a modern airliner. This functionality is simulated here, by requiring that you have the datalink connected before selecting your flight plan for loading. Watch this function for many more features that will be made available to you with the upcoming release of PMDG Global Flight Operations.
Pro-Tip: Right now, both of these functions are simulated, but they ultimately rely upon flight plans located within the PMDG/FLIGHTPLANS directory in your 747 installation. When we unveil PMDG Global Flight Operations, users will find that the datalink function will open to a whole new world of connected data that will actually come from "outside the airplane." Stay tuned!
You can also see the following two videos