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Payloads
JCSAT-13JCSAT-13 is a Communications Satellite operated by the SKY Perfect JSAT Corporation. The satellite features an all Ku-Payload consisting of a total of 44 fixed high-power transponders. In addition to that, the satellite features two steerable antennas to provide Ku-Spot Beams for quick response coverage for all areas within the satellite's field of view. Extensive on-board switching capabilities provide payload reconfiguration on orbit for more efficient communication services. JCSAT-13 will operate from Geostationary Orbit at 124 Degrees East to replace the JCSAT-4A Spacecraft which was launched in 1999. The Satellite will provide coverage for Japan and portions of Asia. The spacecraft is based on the Lockheed Martin A2100AXS Satellite Bus which is an enhanced version of the A2100 design featuring larger power capabilities and greater payload capability supporting bigger payloads. JCSAT-13 has a liftoff mass of 4,500 Kilograms. It features two deployable solar arrays and batteries for power supply as well as a Propulsion System for Orbit Maintenance and Adjustments. One LEROS-1C Liquid Apogee Engine is installed on the Spacecraft and uses Hydrazine and Nitrogen Tetroxide as propellants. Leros 1C has a dry mass of 4.26 kilograms and provides 460 Newtons of thrust. The Spacecraft is expected to be operational for 15 years.
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Photo: ESA/Arianespace/CNES
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Photo: ESA/Arianespace/CNES
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VINASAT-2VINASAT-2 is the second Vietnamese Satellite to be placed in Orbit after the country's first satellite was launched in 2008, also aboard an Ariane 5 Launcher. VINASAT is the national satellite program of the Socialist Republic of Vietnam. The project is planned to provide independence in satellite communications for the country as well as other benefits concerning national security and economic opportunities. The Spacecraft is operated by the Vietnam Post and Telecommunications Group. VINASAT-2 is based on the Lockheed Martin A2100A Satellite Platform and has a mass of approximately 2,970 Kilograms. The satellite is equipped with 24 Ku-Band Transponders that will be used to provide radio, television and telephone transmission services. Operating from an orbital position of 131.8 Degrees East, the satellite is expected to have an on-orbit life of at least 15 years. The spacecraft has two deployable solar arrays and batteries to provide power to the communication payload. VINASAT-2 has its own Propulsion System for on-orbit maneuvers featuring an IHI BT-4 Thruster. BT-4 was developed by IHI Aerospace, Japan and has a dry mass of 4 kilograms and a length of 0.65 meters. The engine provides 450 Newtons of Thrust and uses Hydrazine and mixed Oxides of Nitrogen as propellants.
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Mission Preview and Timeline
| Time | Event | Altitude (km) | Velocity (m/s) | |
| 0:00:00.00 | Vulcain Engine Ignition Sequence | 0 | 0 | |
| 0:00:07.05 | Solid Rocket Booster Ignition | 0 | 0 | |
| 0:00:07.30 | LIFTOFF | 0 | 0 | |
| 0:00:12.60 | Pitch Maneuver | 0.088 | 36.2 | |
| 0.00:17.10 | Roll Maneuver | 0.330 | 72.8 | |
| 0:02:25.00 | SRB Burnout and Jettison | 70.900 | 2002.0 | |
| 0:03:11.00 | Payload Fairing Jettison | 107.400 | 2181.0 | |
| 0:07:21:00 | Acquisition by Natal Tracking Station | 199.000 | 4739.0 | |
| 0:08:54.00 | Core Stage shutdown | 201.100 | 6824.0 | |
| 0:09:00.00 | Stage Separation | 201.100 | 6850.0 | |
| 0:09:04.00 | 2nd Stage Ignition | 201.100 | 6853.0 | |
| 0:13:01.00 | Acquisition by Ascension Tracking Station | 196.300 | 7427.0 | |
| 0:18:56.00 | Acquisition by Libreville Tracking Station | 230.700 | 8206.0 | |
| 0:23:18.00 | Acquisition by Malindi Tracking Station | 480.200 | 9082.0 | |
| 0:25:01.00 | Second Stage Shutdown | 669.900 | 9339.0 | |
| 0:26:35.00 | JCSAT-13 Release | 898.600 | 9148.0 | |
| 0:35:00.00 | Sylda Separation | 2635.000 | 7918.0 | |
| 0:36:01.00 | VINASAT-2 Release | 2881.000 | 7769.0 | |
| 0:48:30.00 | Ariane 5 - End of Mission | 6057.000 | 6222.0 |
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The Countdown for a Launch of the Ariane 5 Rocket begins 11 hours and 30 minutes before the launch window opens. At L-7:30 final electrical checks will be made before Fueling starts just under 5 hours to liftoff. 90 Minutes into LOX and LH2 Tanking, the Vulcain Main Engine is being chilled down by the supercold propellants. 1 hour and 10 minutes prior to launch, final checks of all communication connections and telemetry links are conducted to ensure all Ground Tracking Stations are ready to support the mission. The Vehicle will be placed in a stable configuration for T-7 Minutes and Holding. The Launcher can remain in this configuration throughout the launch window. At T-7 Minutes and Counting, the Synchronized Sequence begins. Computers are watching all parameters of the vehicle and ground support equipment as final reconfigurations are made to put the Ariane in a launch configuration. Should any system show an off-nominal performance, the Computers will automatically recycle all systems to their T-7-Configuration to back out of the automated sequence. 4 Minutes prior to launch, all tanks of the first and second stage are being pressurized for flight. 1 Minute before T-0, the vehicle switches to onboard power. 30 Seconds before Ignition, Water begins flowing into the Flame Trenches. Hydrogen aspiration of the Vulcain engine starts 18 seconds before it is ignited. The Cryogenic arms that are used for critical connections including fuel lines are retracted. 4 seconds before the Ignition Sequence commences, the Handoff to Ariane’s onboard computers occurs and the Guidance System enters its flight mode one second later.
At T-0, the Vulcain Engine Ignition Sequence begins. Three pyrotechnic devices are used to ignite the main engine which reaches flight thrust at T+4.5 seconds. Engine performance is being monitored before the Solid Rocket Boosters are ignited at T+7.05 seconds. Liftoff occurs just a quarter of a second later. The two Solid Rocket Boosters provide 92% of total thrust at blastoff. The launcher climbs vertically for 6 seconds before the pitch maneuver begins which puts the rocket into the proper trajectory that is required to reach the targeted Main Engine Cutoff point. |
Photo: ESA
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After 2 minutes and 21 seconds of
powered flight, the SRBs burn out and are jettisoned to fall back to
Earth and into the Atlantic Ocean. Immediately after SRB jettison, the
onboard computers calculate the precise trajectory that is required to
recover from minimal transients that are nominal for the SRB Phase. That
course correction is conducted in real time by swivalling the main
engine. The next Event is Payload Fairing Jettison. The Fairing is used
to protect the Payloads from thermal loads during atmospheric flight.
When heat levels are at an acceptable level, the fairing is jettisoned
by pyrotechnically initiated separation tubes. Separating the fairing as
early as possible increases ascent performance. At 9 minutes into the
flight, the Vulcain Engine shuts down for first stage cutoff. Stages #1
and #2 separate from each other and the second stage with its HM-7B
engine continue powered flight after the engine ignites. The first stage
falls back to Earth and impacts off the coast of Africa in the Gulf of
Guinea. The second stage will make its first burn before final engine
cutoff. Afterwards, the stage re-orients itself to the proper attitude
to release the first payload. When the first Spacecraft Separation is
successful, the coast phase continues with more orientation maneuvers
and the separation of the Sylda 5. This is a fairing like object that is
used to install two payloads on top of the rocket. The first payload is
mounted atop the Sylda and the second satellite is hidden beneath it
until the first payload is released. With Sylda Separation, the path is
clear to jettison the second and final payload into its targeted orbit.
The second stage continues its mission for several minutes during which
it performs reorientation maneuvers and avoidance firings. After second
stage passivation, Ariane’s mission is complete. The two satellites will
then be in a geostationary transfer orbit that will be optimized when
the spacecraft fire their individual engines to reach a precise
position.
