Eutelsat I F-1

Eutelsat I F-1, also known as European Communications Satellite 1 (ECS-1) is a decommissioned communications satellite operated by the European Telecommunications Satellite Organisation. Launched in 1983, it was operated in geostationary orbit at a longitude of 13° East, before moving to several other locations later in its operational life, before it was finally decommissioned in 1996. It was the first of five satellites launched to form the first-generation Eutelsat constellation.

Eutelsat I F-1

Mission type	Communications
Operator	Eutelsat / ESA
COSPAR ID	1983-058A
SATCAT no.	14128
Mission duration	7 years planned 13 years achieved
Spacecraft properties
Spacecraft type	Eutelsat I
Manufacturer	British Aerospace
Launch mass	1,050 kilograms (2,310 lb)[1]
Start of mission
Launch date	16 June 1983, 11:59:03 UTC[2]
Rocket	Ariane 1
Launch site	Kourou ELA-1
Contractor	Arianespace
Entered service	12 October 1983
End of mission
Disposal	Decommissioned
Deactivated	16 December 1996
Orbital parameters
Reference system	Geocentric
Regime	Geosynchronous
Longitude	10° East (1983) 13° East (1983-88) 16° East (1988-91) 17.5° East (1991-92) 25.5° East (1992-93) 48° East (1993-96) 36° East (1996)[3]
Semi-major axis	42,561.59 kilometres (26,446.55 mi)
Eccentricity	0.0015842
Perigee altitude	36,123 kilometres (22,446 mi)
Apogee altitude	36,258 kilometres (22,530 mi)
Inclination	15.15 degrees
Period	24.27 hours
Epoch	5 June 2014, 10:14:27 UTC[4]
Transponders
Band	12 Ku band 10 used

A Eutelsat I spacecraft, F-1 had a mass at launch of 1,050 kilograms (2,310 lb).[1] Constructed by British Aerospace, it was designed to be operated for seven years and carried 12 Ku band transponders, two of which were set aside as spares. Unlike the later Eutelsat I satellites, F-1 did not have the two additional "SMS beam" transponders in the 12 GHz band.[5] It also only had partial eclipse protection, requiring some channels to be turned off during eclipse periods around the spring and autumn equinoxes.[3] The satellite contained a Mage-2 solid rocket motor to perform orbit circularisation at apogee.[5]

ECS-1 was launched by Arianespace, using an Ariane 1 carrier rocket, flight number L06. The launch took place at 11:59:03 UTC on 16 June 1983, from ELA-1 at Kourou.[2] Successfully deployed into geosynchronous transfer orbit, ECS-1 raised itself into an operational geostationary orbit using its apogee motor. Following commissioning operations conducted by the European Space Agency at a longitude of 10° East, the satellite was moved to its operational slot at 13° East, entering service on 12 October.[3]

After five years in service, Eutelsat I F-1 was replaced by the newly launched Eutelsat I F-4. For the next three years it covered a new slot at 16° East until the launch of Eutelsat II F-3. After brief operations at 17.5 and 25.5 degrees between 1991 and 1993, the satellite was moved to 48 degrees East for most of its last three years of service. Between February and March 1996 the spacecraft was moved to 36 degrees West, where it remained until November.[3] The satellite was decommissioned in December 1996; leaving geosynchronous orbit on 11 December before deactivation on 16 December.[6] As of 5 June 2014 the now-derelict satellite was in a 36123 × 36258 km × 15.15° (22,446 × 22,530 mi) graveyard orbit.[4]

References

1. "EUTELSAT 1". National Space Science Data Center. Retrieved 8 June 2014.
2. McDowell, Jonathan. "Launch Log". Jonathan's Space Page. Retrieved 8 June 2014.
3. "Eutelsat 1F1". The Satellite Encyclopedia. Tag Broadcasting Services. Archived from the original on 4 March 2016. Retrieved 27 December 2020.
4. "EUTELSAT 1-F1 (ECS 1) Satellite details 1983-058A NORAD 14128". N2YO. 5 June 2014. Retrieved 8 June 2014.
5. Krebs, Gunter. "ECS 1, 2, 3, 4, 5 (Eutelsat-1 F1, 2, 4, 5)". Gunter's Space Page. Retrieved 8 June 2014.
6. McDowell, Jonathan. "Geostationary Orbit Catalog". Jonathan's Space Page. Archived from the original on 9 September 2016. Retrieved 8 June 2014.