Post Tue Jul 19, 2011 9:48 am

Ariane 5 rocket aproaches the end of 2010 with a new success

Last launch of November 2010 was performed by the European rocket Ariane 5 with it's fifth out of six flights scheduled for 2010.
Lift off was on 26th of November at 18:39 GMT from Kourou space centre, French Guyana, ELA3 complex, under the flight indicative of V198. This has been again a dual launch configuration (ECA version), this time the satellites on board being Intelsat 17 and Hylas 1 .
Intelsat 17 or IS17 is the newest Intelsat geostationary platform that is to replace the old Intelsat702 satellite (launched 17 June 1994) at the orbital position of 66 degrees East (somewhere above the Indian Ocean), offering communications services to customers in Europe, Africa, Asia and Middle East.
The new satellite, weighting 5540 kg, built on the LS-1300 platform developped by Space Systems/Loral is a telecommunications satellite that will work for about 15 years, using 28 transponders in the C band as well as 46 in the Ku band.
The contract signed in August 2008 with the American company from Palo Alto, California, foresaw a delivery within 2 years; the satellite was built on time, without delays. The earlier Intelsat, IS16 –for which we had a dedicated article- has been built by another provider- the Orbital Sciences Corporation, on its Star2 platform. Currently, Intelsat has problems with one of the recent launched satellites- Galaxy15- the technical failures being related in an recent article.
Intelsat is one of the bigest companies and a pioneer in this domain (must be remembered that in 1965 Intelsat launched the first commercial telecommunications satellite), that is providing even since the foundation in 1964 satellite services, including telecommunications, media-video, data and voice services in about 200 countries for nearly 1800 clients.
Since then Intelsat wrote it's name in history with it's technical accomplishments: for example in 1969 transmitting the first global live tv transmission of the Apollo 11 Moon landing, or in 1974 when the first international digital communications satellite network started.
With a modern fleet numbering almost 50 satellites and 8 ground stations, with a personnel of 1100 and offices in Brazil, China, France, Germany, India, Singapore, South Africa, United Arab Emirates, England and United States, Intelsat recorded 2.4 billion dollars revenues by the end of 2008, consolidating it's position on the global telecommunications market.
By comparison, Hylas 1 is a more special project. It was supposed initially to be launched using a Falcon 9 rocket but in 2009 the intentions changed and a new launch contract was signed with ArianeSpace. On the basis of this new contract the flight was to be executed by the new launcher Soyuz2-1a but, as related in another article, ArianeSpace encountered some problems in the deployment of ground systems for the new rocket (which will finally fly in the beginning of 2011) so in this perspective, in order to be on schedule, the launch of the Hylas 1 satellite was assigned with the Ariane 5 rocket.
Hylas 1(or Highly Adaptable Satellite) is the first satellite in the Hylas constellation constructed by the british operator Avanti Screenmedia Group Plc with headquarters in London. It will work from the orbital position of 33.5 degrees West serving about 22 central and west-european countries (150.000-300.000 users) with the intention of providing broadband internet services and HDTV programs.
Weighting 2570 kg at the launch, the new satellite, built by EADS Astrium on a I-2000 platform initially developed by the ISRO Indian Space Agency, will operate for about 15 years, using 6 transponders in the Ka band and 2 on the Ku band.
It is a three axes stabilized satellite with 4.2 x 2.6 x 2.5m dimensions, having 2 mobile solar panels with GaAs technology, each measuring 2.54 x 1.53m and 2 batteries with 32Ah capacity each, composed of 20 cells.
On board we found a circular antenna with 1.6 m in diameter operating in the Ku band and 2 elliptical antennas 1.6 x 1.35m operating in the Ka band. The two antennas secure communication with Inmarsat East London Control Centre as well as with the two Goonhilly and Land's End ground stations.
But the main characteristics is the GFP technology (Generic Flexible Payload).
Hylas 1 is the first public-private partnership initiated by ESA that is completed with the construction of a satellite and will be followed up in the next 2 years by other similar partnerships with Inmarsat and Hispasat. Financially, the ESA’s contribution was of 34 million euro out of a total amount of 120 millions for the construction of the satellite.
It is in fact a build-up for the ARTES program (Advanced Research in Telecommunication Systems) initiated several years ago by ESA. The partners of this dialogue were BNSC (British National Space Centre) and the Avanti Communications commercial company.
The official guarantee offered by both public institutions and the lobby made by the Avanti company brought in eventually other investors, estimating that the final project investment (satellite and related services/applications) will be in the region of 500 million euro.
Avanti is a company founded in 2007, which itends to be a very dynamic player in the sector of satellite communications. After it recorded in 2008 a net loss of 1 million UK pounds, it had in 2009 a positive profit of 1 million UK pounds and finally the successful launch of the Hylas 1 satellite directly moved up the company's London stock exchange rate, so that it is worth now 604.86 million UK pounds.
Ariane 5 is today the preferred commercial launch vehicle because of it's proven fiability (since December 2002 when the ECA version was introduced and the first flight ended with the loss of the onboard loaded satellites Stentor and Hotbird 7, the rocket has an impressive record of 36 flights without errors).
Ariane 5 has 3 flying versions: GS, ES and ECA. The major diferrence is that the GS version uses a Vulcain 1 propulsor for the first stage, while the rest of the versions use Vulcain 2.
The ECA version is the only commercial launcher capable of carrying a total of 9.6 tons load, composed of the two different platforms (satellites and the added protection and integration equipments).
50.5 m long and with a total mass of 780 tons at liftoff, the launcher uses 2 MPS Europropulsion solid fuel propulsors with a nominal force of 5060 kN (and a reaction time of 130s), a cryogenic main stage Vulcain 2 Snecma with a 1390 kN of thrust (540s burn-time) and a final cryogenic stage ESC-A Astrium Space Transportation using a HM-7B Snecma propulsor with 67 kN and a reaction time of 945s.
Finally, in the top section of the rocket is is integrated the SYLDA internal structure surrounding the two satellites and flight's thermal protection structure developped by Oerlikon Space company.
In 2009, Ariane 5 managed to perform 6 flights (5 in the ECA version and 1 in version 5GS) and the launch of 14 satellites: HotBird10/NSS-9/Spirale A/Spirale B (February), Herschel/Planck (May), TerrStar-1 (July), JC Sat 12/ Optus D3 (August), Amazonas 2/ COMSATBw-1 (October 1), NSS-12/Thor-6 (October 29) and Helios 2B (December 18). For more info please consult the SpaceAlliance related articles from 2009.
In 2010, all Ariane 5 flights were in the ECA version: Astra 3B and ComsatBw2 (March), Arabsat 5A and COMS1 (June), Nilesat 201 and RASCOM-QAF 1R (August), Eutelsat W3B and Bsat 3b (October), and finally Intelsat 17 and Hylas 1.
Next flight of the Ariane 5 rocket and also the last of 2010 will happen on the 26th of December with the Hispasat 1E and Koreasat 6 satellites.
credit ArianeSpace