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|Arianespace will use an Ariane 5 ECA rocket, designated VA202, to launch the ST 2 and GSAT 8 communications satellites. ST 2 will provide fixed and mobile voice and Internet to Asia and the Middle East for ST 2 Satellite Ventures, a joint venture between companies in Singapore and Taiwan. GSAT 8 will serve India with a Ku-band communications payload.ST 2 (SingTel 2) for will be located at 88° east longitude and will provide fixed and mobile services, along with IP-based voice and data services for businesses, particularly for operators offering direct-to-home services, and shipping companies in Asia and the Middle East.
GSat-8 (also known as INSAT-4G) carries 18 Ku band transponders. It will also carry a GPS Aided Geo Augmented Navigation (GAGAN) payload. It has a mission life of 12 years and will be positioned at 55º E longitude.
Launch opportunity:
Universal / UTC
|
Paris / CEST
|
Kourou / GFT
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Washington / EDT
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Bangalore / IST
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Taipei & Singapore / CST & SGT
start:
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20:38
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22:38
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17:38
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4:38 p.m.
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2:08 a.m.
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4:38 a.m.
end:
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22:10
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00:10
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19:10
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6:10 p.m.
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3:40 a.m.
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6:10 a.m.
on:
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May 20, 2011
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May 20/21, 2011
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May 20, 2011
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May 20, 2011
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May 21, 2011
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May 21, 2011
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[highlight]L[eventtimer]2011-5-20 20:38;%c%%ddd%/%hh%:%mm%:%ss%[/eventtimer][/highlight]
There is O-F's calendar event created for this launch, for which you can request a reminder, that will be sent via e-mail on set time before the launch.
Live Coverage Of The Launch:
You can watch the broadcast of the launch live on Arianespace's Videocorner.
The live coverage will start 15 minutes before the window opening time, at about 20:23 UTC / 4:23 p.m. EDT - i.e.[eventtimer]2011-5-20 20:23? in| ;%c% %h%:%mm%[/eventtimer] hours[eventtimer]2011-5-20 20:23?.| ago.;%c%[/eventtimer]
You can also watch the launch on TV via satellite (where available), from: HOT BIRD™ (Transponder 155), 13° East, Frequency: 11604 MHz, Horizontal Polarisation, Symbol rate: 27.500 Msps, FEC 5/6, DVB-S, QPSK, MPEG-2, No encryption / Free to air.
The live coverage will start 15 minutes before the window opening time, at about 20:23 UTC / 4:23 p.m. EDT - i.e.[eventtimer]2011-5-20 20:23? in| ;%c% %h%:%mm%[/eventtimer] hours[eventtimer]2011-5-20 20:23?.| ago.;%c%[/eventtimer]
You can also watch the launch on TV via satellite (where available), from: HOT BIRD™ (Transponder 155), 13° East, Frequency: 11604 MHz, Horizontal Polarisation, Symbol rate: 27.500 Msps, FEC 5/6, DVB-S, QPSK, MPEG-2, No encryption / Free to air.
Launch Vehicle:
Ariane 5 ECA
Height| up to 52 m
Diameter| up to 5.4 m
Liftoff mass| 780 tonnes
Payload mass| 9.6 tonnes
The latest version of the Ariane 5 launcher, Ariane 5 ECA, is designed to place payloads weighing up to 9.6 tonnes into GTO. With its increased capacity, Ariane 5 ECA can handle dual launches of very large satellites.
Ariane 5 ECA: new elements
Ariane 5 ECA is an improved Ariane 5 Generic launcher. Although it has the same general architecture, a number of major changes were made to the basic structure of the Ariane 5 Generic version to increase thrust and enable it to carry heavier payloads into orbit.
Solid boosters (EAP)The EAP boosters’ upper segment of the Ariane 5 ECA (also known as segment S1) carries 10% (2.5 tonnes) more propellant. This extra propellant gives the Ariane 5 ECA an additional 50 tonnes of thrust in the first 20 seconds following liftoff. This means that together the twin boosters deliver a thrust of 1300 tonnes at liftoff, nearly 10 times the level delivered by the new engine of the central stage.
Main stage (EPC and Vulcain 2 engine)An improved version of the Vulcain engine was developed and used on the Ariane 5 ECA version. The Vulcain cryogenic engine was modified to increase its thrust by 20%, up to 137 tonnes. This new Vulcain 2 operates under slightly higher pressure with a mixture ratio that has 20% more liquid oxygen than the Vulcain 1. Because of this change in the mixture, a new oxygen turbopump was developed. In addition, the Vulcain 2 turbopump exhausts are reinjected into the main system, thus improving engine performance at high altitude. The Vulcain 2 engine is a key contributor to the additional lift capability of the new Ariane 5 ECA version into GTO.
To hold the extra liquid oxygen needed for the EPC core stage, the capacity of the liquid oxygen tank has been increased by 16 tonnes. This was achieved by relocating the common tank bulkhead between the liquid oxygen tank and the liquid hydrogen tank of the Ariane 5 Generic EPC stage and reinforcing the structure elements.
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The launcher’s attitude and trajectory are totally controlled by the two onboard computers, located in the Ariane 5 vehicle equipment bay (VEB).
7.05 seconds after ignition of the main stage cryogenic engine at T-0, the two solid-propellant boosters are ignited, enabling liftoff. The launcher first climbs vertically for 6 seconds, then rotates towards the East. It maintains an attitude that ensures the axis of the launcher remains parallel to its velocity vector, in order to minimize aerodynamic loads throughout the entire atmospheric phase, until the solid boosters are jettisoned. Once this first part of the flight is completed, the onboard computers optimize the trajectory in real time, minimizing propellant consumption to bring the launcher first to the intermediate orbit targeted at the end of the main stage propulsion phase, and then the final orbit at the end of the flight of the cryogenic upper stage. The main stage falls back off the coast of Africa in the Atlantic Ocean (in the Gulf of Guinea).
On orbital injection, the launcher will have attained a velocity of approximately 9350 meters/second, and will be at an altitude of about 658 kilometers.
The fairing protecting the ST-2 and GSAT-8 spacecraft is jettisoned shortly after the boosters are jettisoned at about T+189 seconds.
Launch Preparations:
Arianespace mission updates:
- 2011-03-11: A new numbering system for Arianespace missions as preparations begin for another Ariane 5 launch
- 2011-03-18: Assembly begins for another Ariane 5 at the Spaceport
- 2011-03-22: A “double kick” for the third Ariane 5 to be launched in 2011
- 2011-03-24: Another Ariane 5 completes its initial build-up at the Spaceport
- 2011-04-04: India’s GSAT-8 is delivered to French Guiana for its Ariane 5 launch
- 2011-04-06: Mitsubishi Electric’s ST-2 satellite arrives in French Guiana for launch on Ariane 5
- 2011-04-25: GSAT-8 is put through its paces in preparation for Arianespace's Ariane 5 launch on May 19
- 2011-05-03: Ariane 5 makes its first rollout for Arianespace’s next heavy-lift mission
- 2011-05-09: ST-2’s installation on SYLDA marks the start of final payload integration for Ariane 5’s next mission
- 2011-05-13: Preparations for Arianespace’s third Ariane 5 mission of 2011 move into their final phase
- 2011-05-17: The upcoming Ariane 5 mission with GSAT-8 and ST-2 is given its “go” for launch
- 2011-05-17: Arianespace Flight VA 202; Ariane 5 ECA - ST-2 - GSAT-8: Launch delayed by 24 hours
- 2011-05-19: Ariane 5 is in the launch zone for Arianespace’s dual-payload mission with GSAT-8 and ST-2
In pictures:
- The MN Colibri arrives in French Guiana with launcher components for Arianespace’s third Ariane 5 mission to be performed in 2011:
- After docking at Pariacabo Port in French Guiana, the MN Colibri is ready to open its forward ramp, allowing its cargo to be unloaded using the ship’s roll-on/roll-off design:
- The Ariane 5 for Arianespace’s mission in May with the ST-2 and GSAT-8 satellites is lowered into position over its mobile launch table inside the Spaceport’s Launcher Integration Building:
Larger version of left picture | Larger version of center picture | Larger version of right picture
- One of two solid propellant boosters for Arianespace’s heavy-lift mission in May is transported to the Spaceport’s Launcher Integration Building for integration with the Ariane 5’s core cryogenic stage:
- Ariane 5 completes its initial build-up:
- GSAT-8 is unloaded from the Antonov An-124 cargo jetliner at Cayenne’s Rochambeau International Airport in French Guiana:
- The An-124 freighter that brought Mitsubishi Electric's ST-2 satellite to French Guiana is unloaded at Rochambeau International Airport:
- The opening of GSAT-8’s multi-segment solar panel is shown in the Spaceport’s S5 payload preparation facility with a fish-eye lens photo (at left), which distorts the surrounding support structure used for this test milestone. At right, members of the GSAT-8 team examine the satellite’s parabolic antenna following its deployment:
- The Ariane 5 for Arianespace’s next heavy-lift mission rolls out from the Launcher Integration Building in the foreground. Moving to the left, it follows a semi-circular rail track that will take the vehicle to the Spaceport’s Final Assembly Building, located in the background (at right):
- ST-2 is lowered into position on the SYLDA dual-payload dispenser inside the Ariane 5’s Final Assembly Building in French Guiana:
- GSAT-8 is hoisted inside the Spaceport’s Final Assembly Building (photo at left) for its integration atop the Ariane 5 for Arianespace’s upcoming mission (center photo). In the photo at right, GSAT-8 is shown installed on its launcher in the background, while visible in the foreground are propellant feed arms that lead from the Ariane 5 mobile launch table’s mast to the vehicle’s cryogenic upper stage:
Larger version of left picture | Larger version of center picture | Larger version of right picture
- This photo sequence highlights integration activity performed inside the Spaceport’s Final Assembly Building, where the payload fairing containing ST-2 was lowered over GSAT-8 to create Ariane 5’s dual-payload “stack”:
Larger version of left picture | Larger version of middle picture | Larger version of right picture
- Riding atop its mobile launch table, Ariane 5 nears the completion of its rollout today at the Spaceport with the ST-2 and GSAT-8 spacecraft:
Links:
- http://www.arianespace.com/images/launch-kits/launch-kit-pdf-eng/ST-2-GSAT-8.pdf
- http://www.arianespace.com/images/launch-kits/launch-kit-pdf-frn/ST-2-GSAT-8 (FR).pdf
- http://www.arianespace.com/images/launch-kits/poster-pics/ST-2-GSAT-8.pdf
- http://www.astrium.eads.net/media/document/launch-kit-flight-202-ariane-5.pdf
- http://www.videocorner.tv/
- http://spaceflightnow.com/ariane/va202/prelaunch/
- http://space.skyrocket.de/doc_sdat/gsat-8.htm
- http://space.skyrocket.de/doc_sdat/st-2.htm
Due to lack of time, this post will be updated with more information about the payload, ascent timeline, and injection orbit parameters, but only after the launch.
