ACARS notifiy ends in "unable"

Hi,
I mostly depart from german airports. Many of them recommend using ACARS to get an IFR clearance (like EDDM). But when I notify ATC via ACARS I got “unable” the second time in row.

How widely used is ACARS really? Does “unable” mean that ACARS is currently not available at this station? Or does it indicate an error on my side?

regards
Daniel

The error lies with you: for everything around “PDC” (Pre Departure Clearance) you must not notify/logon to the local ATCO. Sending a PDC request and receiving the actual clearance through ACARS is a pure text transmission only. Just follow the guidelines by using the correct address where to send the PDC request to (usually the airport ICAO code). Notifying/logging on is only required for CPDLC, enroute.

Ah, thx. Looks like I was in the wrong menu. Correct should be:

MCDU MENU → ATSU → AOC

right?

Correct!

thanks this is useful, I’m currently writing a PDC request function for VSR for both VATSIM messaging (such as the US) and ACARS/Hoppie telex messaging.

Do the ATC systems automatically process the request or is there a human undertaking a check before issuing the clearance? Also is there a standard format for the request, I am generating the following:

REQUEST PREDEP CLEARANCE NJE123 HDJT TO EGPH AT EGKK STAND 3 ATIS ALPHA EOBT 1205Z FLIGHT RULES IFR

I also assume from the FBW documentation that a response is required - is this standard or do some stations take a change of transponder as an acceptance?

thanks

This probably does all you want to implement as well, might be a good starting point