EUROCAE ED-175 PDF

This document supports the provision of AIS and MET data link services as components of the Data Link Flight Information Services (DFIS) application as defined in ICAO Doc 9694, Manual of Air Traffic Services Data Link Applications [Ref. 7.]. The AIS/MET data link services are intended to be provided to airspace users in various airspace environments, i.e. managed continental airspace (ED1) and unmanaged airspace (ED2), see Section 3.

The operational concept describes the delivery of digital AIS/MET data to aircraft within the area of responsibility of the AIS/MET Data Link Service Provider (DLSP). For the provision of its service(s), the DLSP relies on data / information from approved sources(s)² and on the most suitable data link communications means between the ground and the aircraft from Communications Service Provider(s). The service provision is independent of the air traffic control service and may be provided by State as well as commercial providers.

The operational concept assumes that the AIS/MET data will be the same as used by air traffic control. This will, in particular, ensure consistent information is shared by the various users participating in air traffic management (ATM). A typical application example is CDM.

The AIS/MET data source(s) are considered outside the scope of this SPR document and the data they provide are assumed correct. In addition, sources providing other data types (e.g. Flight Plan) necessary for an efficient implementation of the AIS/MET data link services are also outside the scope and their data are assumed correct. This SPR, notably in its Safety analysis, only considers errors in the AIS/MET data that are introduced by the data link system components. On the aircraft side, the flight crew interaction as well as the end use of the information performed by cockpit avionics (i.e. Flight Management System or display system) were considered in the analyses but are outside the scope of this SPR.

This document provides Safety and Performance Requirements for the following AIS/MET data link services based on the service descriptions provided in the OSED [Ref. 1.] and outlined in this document:

a. AIS service:

• Data Link Aeronautical Update Service (D-AUS); Section 4.2

b. MET services :

• Data Link Weather Planning Decision Service (D-WPDS); Section 4.3

• Data Link Weather Near-Term Decision Service (D-WNDS); Section 4.4

• Data Link Weather Immediate Decision Service (D-WIDS); Section 4.5

NOTE: The OSED includes two additional AIS/MET Data Link services: the AIS Baseline Synchronization Service (Complete Synchronization and Update Synchronization) and the MET Weather Downlink / Crosslink Service. The basic concepts for these services are sound but the safety and performance analyses for these services have been deferred until a clear need is identified and candidate architecture(s) for implementation defined. Development of the corresponding SPR will then have to be considered by appropriate committees / working groups.

FIGURE 1-1 presents a notional architecture of the system considered during the development of this SPR. This notional architecture illustrates a four component system used to support the safety and performance analyses and does not preclude the implementation of a different architecture.

The four components considered for the development of this SPR are:

• Ground Data Link Processing (GDLP);

• Ground Transceiver (GDLP/tr);

• Onboard Data Link Processing (ODLP);

• Onboard Transceiver (ODLP/tr).

Because this SPR is based on a notional architecture, the content and format of AIS/MET messages cannot be specified at this stage. These will have to be addressed at the time of the implementation of candidate data communications architectures and may be the subject of future standards documents.

NOTE: The security assessment for the transmission of AIS and MET data is out of the scope of this document.

PURPOSE

The aim of AIS and MET data link services is to provide aeronautical and meteorological information for flight efficiency and/or hazard avoidance in all flight environments. This information provides a common operating picture between the aircraft and the ground. It is intended to meet operational and regulatory requirements for flight crew decision support (i.e. enabling informed flight crew participation in CDM) and other actors on the ground who will be enabled, through a concept like SWIM to share the same information.

This document defines and allocates the set of baseline minima for the operational, safety, and performance requirements for implementation of AIS and MET Data Link services. These requirements are based on the data link delivery being the primary means of communication between the air and the ground, and the application of the AIS and/or MET information supporting tactical as well as strategic decisions. Voice is considered the secondary means of communications.

This document provides a framework and a methodology to be used as the basis for assessing implementation of new data link systems or architectures as candidates for AIS and/or MET data link services. It can also be used to support the processes that are required to enable Air Traffic Services (ATS) provider operational approval for the AIS/MET data link services.

² In the whole document, the expression "approved source" should be understood as "a data source that has been officially recognized by the relevant State authority."