Intelsat 26

Intelsat 26 was known as JCSAT-5 before launch and as JCSAT-R until it was sold to Intelsat in 2009. It is a geostationary communications satellite designed and manufactured by Hughes (now Boeing) on the HS-601 platform. It was originally ordered by JSAT Corporation, which later merged into the SKY Perfect JSAT Group. It has a mixed K_u band and C band payload and was used as an on orbit spare.[4][2]

JCSAT-4 → JCSAT-R → Intelsat 26

Names	JCSAT-4 (Dec 1995 to Feb 1997) JCSAT-R (Feb 1997 to Late 2009) Intelsat 26 (Late 2009 onward)
Mission type	Communication
Operator	Intelsat
COSPAR ID	1997-007A[1]
SATCAT no.	24732[2]
Spacecraft properties
Spacecraft	JCSAT-4
Bus	HS-601
Manufacturer	Hughes
Launch mass	3,105 kg (6,845 lb)
Dry mass	1,841 kg (4,059 lb)
Dimensions	26.2 m × 7.5 m (86 ft × 25 ft) with solar panels and antennas deployed.
Power	5 kW
Start of mission
Launch date	01:42:00, February 17, 1997 (UTC) (1997-02-17T01:42:00Z)[1]
Rocket	Atlas IIAS
Launch site	Cape Canaveral LC-36B
Contractor	International Launch Services
Orbital parameters
Reference system	Geocentric
Regime	Inclined geosynchronous
Longitude	64.2106°E
Eccentricity	0.0492
Perigee altitude	35,767.40 kilometres (22,224.83 mi)
Apogee altitude	35,805.57 kilometres (22,248.55 mi)
Inclination	6.9714°
Period	23:56:07.2 hours
Epoch	00:00:00 2016-08-11[3]
Transponders
Band	Ku band: 12 × 36 Mhz + 16 × 27 Mhz C band: 12 x 36 MHz
Bandwidth	1,296 MHz
TWTA power	Ku band: 4 × 36 Mhz: 95 Watts 8 × 36 Mhz: 63 Watts 16 × 27 Mhz: 63Watts C band: 12 x 36 MHz: 34 Watts
JSAT

Satellite description

The spacecraft was designed and manufactured by Hughes on the HS-601 satellite bus. It had a launch mass of 3,105 kg (6,845 lb), a dry mass of 1,841 kg (4,059 lb) and a 12-year design life. When stowed for launch, its dimensions were 2.8 m × 4.9 m × 3.8 m (9 ft 2 in × 16 ft 1 in × 12 ft 6 in). With its solar panels fully extended it spanned 26.2 m (86 ft), and its width when its antennas were fully deployed was 7.5 m (25 ft).[4] Its power system generated approximately 5 kW of power due to two wings with four solar panels each.[5][4] It also had a single NiH₂ battery composed of 30 cells and a 200Ah charge.[4] It would serve as on orbit backup for the JSAT fleet.[4]

Its propulsion system was composed of an R-4D-11-300 LAE with a thrust of 490 N (110 lb_f). It also used had 12 22 N (4.9 lb_f) bipropellant thrusters for station keeping and attitude control. It included enough propellant for orbit circularization and 12 years of operation.[4]

Its payload is composed of four octagonal antenna fed by twelve 36 MHz and sixteen 27 MHz K_u band plus twelve 27 MHz C band transponders for a total bandwidth of 1,296 MHz.[5][4] Eight of the 36 MHz and the sixteen 27 MHz K_u band transponders have a TWTA output power of 63 Watts, the other four 36 MHz ones have 95 Watts. It can configure four 27 MHz transponders into a single 54 MHz with an effective 125 Watts.[4] The twelve C band transponders have 36 MHz bandwidth and 34 Watts of power.[4]

History

In December 1995, JSAT ordered its fourth satellite from Hughes, and second of the HS-601 platform, the JCSAT-4. It was an almost copy of the JCSAT-3, also based on the HS-601, but with more powerful transponders. It would have a mixed K_u band and C band payload, a power generation capability of 5,000 Watts and a 12 year of design life. It was expected to be delivered by early 1997 and be positioned at the 124°East longitude. It would provide telecommunications and television services to Japan, all of Asia, Hawaii and Australia and New Zealand.[4][6]

On March 25, 1996, International Launch Services announced a contract with JSAT for the launch of JCSAT-4 aboard an Atlas IIAS. At the time it was expected to launch in January 1997 from Cape Canaveral LC-36A launch pad. This was the second contract of ILS with JSAT after the successful launch of JCSAT-3 in August 1995.[7]

On February 18, 1997 at 01:42:00 UTC, and Atlas IIAS launched from Cape Canaveral LC-36B with JCSAT-4 towards a geosynchronous transfer orbit.[8] After the successful launch, it was renamed JCSAT-R. During its tenure as JCSAT-R it operated on the 124°East longitude.[4] On August, 2008, JSAT was merged into the SKY Perfect JSAT Group.[9]

In late 2009 Intelsat bought JCSAT-R and rechristened it Intelsat 26.[10][4] In March 2010, Intelsat announced an agreement with Türksat for loaning Intelsat 26 so the latter could keep its orbital rights until a new satellite could be launched.[10]

In July 2010 it was positioned at the 50°East longitude with a 3.4° inclination.[11] By January 2013 the inclination had increased to 4.6°.[12] In August 2016, the satellite was positioned at 64.1°East with a 6.97° inclination.[13][3]

References

1. "JCSAT 4". NASA Space Science Data Coordinated Archive. 27 April 2016. Retrieved 2016-08-04.
2. "Intelsat 26". Satbeams. Retrieved 26 July 2016.
3. "Detailed satellite data for INTELSAT 26 (IS-26) 64.1°E". satellite-calculations.com. Retrieved 2016-08-11.
4. Krebs, Gunter Dirk (2016-04-21). "JCSat 3, 4 (JCSat R) → Intelsat 26". Gunter's Space Page. Retrieved 2016-07-20.
5. "Hughes Built JCSAT-4 To Boost Services In Pacific Rim". warunasat.com. Hughes. February 14, 1997. Retrieved 2016-08-11.
6. "JSAT Orders New Communications Satellite From Hughes". warunasat.com. Hughes. February 2, 1996. Retrieved 2016-08-11.
7. "Japan Satellite Systems, Inc. Selects Atlas For Launch Of JCSAT 4". warunasat.com. ILS. March 25, 1996. Retrieved 2016-08-11.
8. "Atlas Successfully Launches Japanese Comm Satellite". warunasat.com. ILS. February 16, 1997. Retrieved 2016-08-11.
9. "Notice of Merger of Consolidated Subsidiaries" (PDF). SKY Perfect JSAT Corporation & Intelsat. August 6, 2008. Retrieved 2016-08-03.
10. de Selding, Peter B. (March 18, 2010). "Turksat To Use Borrowed Intelsat Craft as Placeholder". Space News. Retrieved 2016-08-11.
11. "Intelsat 26 (50.0E)". warunasat.com. July 21, 2010. Retrieved 2016-08-11.
12. "Intelsat 26 (50.0E)". warunasat.com. January 27, 2013. Retrieved 2016-08-11.
13. "INTELSAT 26 (JCSAT 4)". n2yo.com. Retrieved 2016-08-11.