ICAO Seminar on the Implementation of Datalink and SATCOM Communications Bangkok, 17-19 November 2003 Satellite AIRCOM Infrastructure Reinforcement Akhil Sharma

Introduction This presentation explains the steps SITA is taking to reinforce the Satellite AIRCOM network infrastructure to ensure the long-term availability of the service to the customers (airlines and air traffic service providers) and to improve its reliability.

SITA use of Inmarsat Aeronautical Ground Stations Satellite AIRCOM service is provided via the 4 Inmarsat-3 satellites. SITA has to obtain access to the satellites via the operators of the ground stations that interconnect the satellite links to ground networks. The primary Satellite AIRCOM ground station operators are France Telecom and Xantic (the Inmarsat subsidiary of Telstra and KPN). The backup Satellite AIRCOM ground station operators are KDDI Japan and Stratos (the Canadian operator that bought the Inmarsat division of British Telecom).

SITA use of Inmarsat Aeronautical Service INMARSAT Atlantic Ocean East and West Satellites INMARSAT Indian and Pacific Ocean Satellites AA SQ Stratos Backup KDDI Backup AF France Telecom Primary XANTIC Primary QF Public telephone network access for passenger telephone calls SITA Data Link Processor SITA Telephony billing system

Inmarsat ground station operators providing aeronautical service Atlantic West France Telecom Telenor USA Stratos UK Atlantic East France Telecom Telenor Norway Stratos UK Indian Ocean XANTIC Australia Telenor Norway Singapore Telecom KDDI Japan Pacific Ocean XANTIC Australia Telenor USA Singapore Telecom KDDI Japan SITA Skyphone These ground stations are all single units with antennae linking to two satellites, except for the Telenor USA stations that are separate units on the east and west coasts of the USA.

Inmarsat ground station operator provision of aeronautical service The Inmarsat ground station operators that implemented aeronautical service invested heavily in the acquisition of the equipment. Passenger telephony usage has been too low to finance a fundamental upgrade so they still have computers developed in the 1980’s. Several Inmarsat ground station operators that implemented aeronautical service have switched the service off due to lack of usage. The latest is Singapore Telecom who will close the service down in March 2004, requiring the partner Stratos to seek alternative arrangements.

Inmarsat provision of Aeronautical Service Aeronautical service is not the primary business of Inmarsat: Maritime and increasingly land mobile terminals are the main users of the Inmarsat and their new 4th generation satellite will focus on land mobile. Aeronautical service in 2002 generated only 3% of the Inmarsat revenue. Inmarsat has developed the Swift64 service based on their land mobile service which makes more efficient use of the satellites. SITA is working with Inmarsat to maintain their interest in providing the classic aeronautical service and find ways to make it available through the new satellites.

Inmarsat Aeronautical Ground Station Equipment The Inmarsat aeronautical ground stations still use the computers installed at service launch around 1990. All the aeronautical stations use equipment developed by a company called Nera specialized in Inmarsat systems, except the KDDI Japan station which uses Toshiba equipment that is no longer supported. Only 2 ground stations per satellite, including the SITA primary stations, have been upgraded to support the enhanced Aero H+/I services that use spot beams.

Aeronautical Ground Station Upgrade The aeronautical ground station use old computers that limit performance and need to be replaced. Ground station computers have components that are reaching the end of their useful life and have a software framework that limits capacity. Aircraft numbers and ACARS usage are reaching the limits of the ground station systems. ACARS/data performance was not the focus when the ground stations were developed 15 years ago primarily to provide voice service. Expanding ATS/FANS use of satellite ACARS requires improved performance levels.

SITA commitment to Inmarsat service SITA is committed to providing service to the Satellite AIRCOM customers who operate over 66% of the 2000 air transport aircraft with Inmarsat avionics. SITA is working with Inmarsat and the ground station operators including France Telecom and Xantic to define a replacement strategy for the aeronautical service computers to guarantee the service availability up to 2010 and beyond. SITA will ensure the ground station upgrade provides performance improvements and deals with the Inmarsat 4th generation introduction.

SITA use of Japanese satellites SITA is working with the Japan Civil Aviation Bureau (JCAB) which will launch 2 satellites providing service compatible with Inmarsat. JCAB has selected SITA to market to airlines the use of their MTSAT satellites, that they will launch in 2004 and 2005. SITA will ensure that the Satellite AIRCOM service provided via the Japanese satellites is the same as via Inmarsat so that the switch is transparent to the user aircraft. The addition of these new satellites alongside the Inmarsat satellites will reinforce the Satellite AIRCOM infrastructure.

Conclusion SITA led the implementation of the Inmarsat Aeronautical service as the first organization to package passenger and cockpit services. Airlines have equipped 2000 aircraft to use the Inmarsat service and now rely on its availability especially for ACARS data link in oceanic and remote areas. SITA is committed to maintaining access for aircraft operators to Inmarsat aeronautical service and is leading the efforts to upgrade the ground station network.