Update the definition of the D-ATIS Data Link Service such that it allows the transmission of the extended length messages of the ICAO Global Reporting Format (GRF). ED-89A describes the requirements for a Data Link Service providing D-ATIS data over ACARS. One of the requirements stated in ED-89A is a maximum message length of 800 Characters. ICAO has developed a new format for the reporting of runway conditions as part of ATIS: the GRF (Global Reporting Format). Because of the new structure and additional reporting requirements, ATIS messages can become significantly longer (in particular for complex aerodromes in adverse weather conditions). Taking into account the requirement for D-ATIS messages containing identical information as Voice ATIS, this will result in a increase of the length of D-ATIS messages beyond 800 characters. Investigation across manufacturers and Data Link Service Providers (DSP) showed that most avionics can cope with longer D-ATIS messages and that the ACARS Data Link should be able to transmit those messages. However, the DSPs were not certain that this can be achieved respecting all requirements stated in ED-89A. Therefore it was not possible to simply increase the maximum message length. Rather the reservations of the DSPs were covered in a note added to ED-89A. The Change 1 to ED-89A has to be considered as complementing ED-89A by opening the possibility for D-ATIS message to be longer than 800 characters.