In-orbit Tests of INMARSAT I-4 F1 Completed Successfully

World’s most sophisticated geostationary satellite fully deployed in orbit; being moved to operational position

All systems performing as expected; payload meeting all performance targets

Successful RF tests completed and digital beam forming successfully demonstrated; highly promising for outstanding mission performance.

London/Toulouse, 3 May 2005 – The Inmarsat-4 F1 satellite has successfully completed in-orbit tests following its launch on 11th March 2005. Early orbit operations have progressed as planned, and all spacecraft functions are performing well. The spacecraft will now take the next three weeks to be moved from its test location at 8° East longitude to its operational station at 64°E before service commences.

This is the first of three spacecraft built by EADS Astrium for Inmarsat that will provide capacity for existing services and the forthcoming Broadband Global Area Network (BGAN) service, delivering voice and high-speed data connectivity to mobile users. In-orbit end-to-end system tests including the ground segment are currently being performed by Inmarsat.

The Inmarsat team in London, supported by engineers from EADS Astrium, took control and began operating the I-4 F1 following its launch into super-synchronous transfer orbit on 11th March 2005. The satellite experienced its first eclipse just 33 hours after launch, and arrived in geosynchronous orbit on 22nd March, after two apogee burns and two perigee burns. Following the deployment of its 45m wingspan solar array and 80 square metre antenna reflector, the satellite acquired on-station attitude in nominal solar sailing mode and began using the plasma propulsion system.

After the payload was turned on at the end of March, the first high speed control links were successfully established between the satellite and the access station at Fucino, Italy, through the on-board digital signal processor, and all active hardware has been confirmed as operational. The satellite is now available for operational use after in-orbit tests have verified that all systems are operating as specified. This included antenna pattern measurements, passive intermodulation and the testing of main communications parameters, which have been completed successfully. All tests performed so far have shown compliant results for the key performance parameters.

“The flawless operation and testing since launch is a real tribute to all those who have worked so hard to make it happen, and gives us great confidence that the satellite will meet its predicted mission performance,” said Michel Le Moine, Inmarsat-4 Project Manager for EADS Astrium.

Franco Carnevale, Programme Director for Inmarsat, said: “I am most impressed by the performance and professionalism of the Inmarsat and EADS Astrium teams, not only for the design, assembly and test of the spacecraft, but also in the running of the in-orbit operations with Inmarsat.”