ARINC Characteristic 781-9:2024

This document sets forth the desired characteristics of an aviation satellite communication (satcom) system intended for installation in all types of commercial transport and business aircraft. This document provides general and specific guidance on the form factor and pin assignments for the installation of the avionics primarily for airline use. It also describes the desired operational capability of the equipment to provide data and voice communications, as well as additional standards necessary to ensure interchangeability. This Characteristic specifies equipment using Inmarsat satellites operating in L-band. Ku-band and Ka-band equipment are specified in ARINC Characteristic 791, ARINC Characteristic 792, and ARINC Characteristic 793.





Supplement 8 added Diplexer Low Noise Amplifiers (DLNA) to protect Inmarsat's Classic Aero and SwiftBroadband satcom equipment from possible ground-based LTE and ATCt (Ligado) interference.





Supplement 9 expands the Dual Satcom Operation description, including the Dual Dissimilar Active/Passive Satcom configuration. ATN/IPS Interface Provisions and Guidance is also added in Supplement 9.