ARINC 841-1

The scope of this specification covers all the provisionsnecessary to enable communication of large messages betweenairborne and ground applications without degradation of theavailability required of air-ground links to deliver Air TrafficService (ATS) messaging in a timely manner.

This standard defines a communication protocol for air-groundcommunications aiming at:

• Exchanging AOC messages of any type between aircraft andground to take place over ARINC 618 networks, without currentnetworks limitation (e.g., 3360 bytes maximum size limitation forACARS downlinks, 3520 bytes for ACARS uplinks)

• Allowing existing ARINC 620 AOC exchanges between ground andaircraft to occur over IP networks

The standard is intended to be used only for AOC exchanges, butits design should not preclude future use by Air Traffic Control(ATC).

The provisions defined in this document include specificationsfor:

• Communication services provided to the users

• Messages format and content

• Messages encoding and compression

• Protocols for exchanging messages over the differentsubnetworks

The standard provides guidelines and recommendations on themaximum message size that can be transmitted over the ACARSsubnetworks, in order to preserve RF bandwidth and not degrade theoverall ACARS availability.

Purpose of Document

The purpose of this document is to provide an industry standardfor Media Independent Aircraft Messaging (MIAM) which permits theexchange of a large volume of data over Aircraft CommunicationsAddressing and Reporting System (ACARS) subnetworks or broadbandInternet Protocol (IP) subnetworks.

The volume of data transmitted over ACARS datalink isincreasing, notably on new generation aircraft. Althoughavailability of new IP-based communication systems providesadditional communication paths, ACARS will continue to be used forAeronautical Operational Control (AOC) message transmission.

There is thus a need for a protocol that allows avionic systemsto exchange large volumes of data (larger than the maximum ACARSmessage) over ACARS subnetworks (VHF Digital Link Mode 2 (VDL2) ortraditional ACARS subnetworks under certain conditions) as well asbroadband IP subnetworks.

ARINC Specification 841 was developed to:

• Improve ACARS performance and efficient Radio Frequency (RF)spectrum utilization

• Define a communication service common to ACARS and IPsubnetworks Provide ACARS access to new datalink users (e.g.,Electronic Flight Bag (EFB) applications)

• Avoid proliferation of proprietary solutions

 

Edition:

13

Published:

06/20/2013

Number of Pages:

117

File Size:

1 file , 1.8 MB