SpaceX Falcon 9 V1.1 - SES-8 - Launching December 3, 2013
Screenshot from SpaceRef Business copy of SpaceX Webcast of the launch of SES-8
Mission Rundown: SpaceX Falcon 9 V1.1 - SES-8
Written: February 5, 2021
Let’s go higher - Geostationary Orbit
On December 3, 2013 SpaceX successfully completed its first geostationary transfer mission, with the Falcon 9 rocket delivering the SES-8 satellite to its targeted 295 x 80,000 km orbit. Falcon 9 executed a picture-perfect flight, meeting 100% of mission objectives.
SpaceX launched the SES-8 satellite this evening on a Falcon 9 rocket. Launch occurred as the window opened at 5:41 pm EST. Second stage reignition and burn was a success. The SES-8 spacecraft is now in a nominal GEO transfer orbit. So far it seems that the flight was completely nominal.
Falcon 9 lifted off from Space Launch Complex 40 (SLC-40) at 5:41 PM Eastern Standard Time. Approximately 185 seconds into flight, Falcon 9's second stage's single Merlin 1D vacuum engine ignited to begin a five minute, 20 second burn that delivered the SES-8 satellite into its parking orbit.
18 minutes after injection into the parking orbit, the second stage engine relith for just over one minute to carry the SES-8 satellite to its final geostationary transfer orbit. The restart of the Falcon 9 second stage is a requirement for all geostationary transfer missions.
Today's mission marked SpaceX's first commercial launch from its central Florida launch pad and the first commercial flight from the Cape Canaveral Air Force Station in over five years. SpaceX has nearly 50 satellite launches on manifest, of which over 60% are for commercial customers.
This launch also marks the second of three certification flights needed to certify the Falcon 9 to fly missions for the U.S. Air Force under the Evolved Expendable Launch Vehicle (EELV) program. When Falcon 9 is certified, SpaceX will be eligible to compete for all National Security Space (NSS) missions.
The Payload
The SES-8 satellite is built on the STAR-2.4 satellite bus by Orbital Sciences. It is the sixth satellite of that model to be built for SES.
The communications satellite is initially co-located at 95.0° East with NSS-6 in order to provide communications bandwidth growth capacity in the Asia-Pacific region, specifically aimed at high-growth markets in South Asia and Indo-China, "as well as provide expansion capacity for DTH, VSAT and government applications".
Specifications
Payload mass: 3,170 kilograms (6,990 lb)
Electrical power: 5 kW, using Gallium arsenide solar panels, and two 4,850 watt-hours (17,500 kJ) lithium-ion storage batteries
Battery backup: 4850 Watt-hour lithium-ion battery
SES-8’s propulsion system is a BT-4 monopropellant engine by IHI Corp.
24 Ku band transponders as communications broadcasting payload
1 small Ka band communications payload
3 main reflector dishes - Two side and one center reflector
Service life: 15 years before allotted station keeping propellant runs out
A second burn of the upper stage was required, and was completed successfully, during the SES-8 mission in order to place the SES-8 tele communications satellite into the highly elliptical supersynchronous orbit for satellite operator SES from ground stations to effect a plane change and orbit circularization.
The launch of SES-8 marks the first time SpaceX will deliver a satellite into geostationary transfer orbit, although it is not the first contract they have received to launch such a payload. Avanti Communications had previously ordered a Falcon 9 to deploy its Hylas-1 satellite, however following delays with the Falcon 9’s development this payload switched to an Ariane 5.
The SES-8 launch was the first commercial ComSat launch to occur from SLC-40 in 20 years, and the fourth such launch from the complex overall. The 3 previous commercial launches were all made by Commercial Titan III (CT-III) rockets; a hybrid of the Titan III(34)D and Titan IV aimed at the commercial geostationary launch market.
In the early hours of 1 January 1990, or late on 31 December 1989, a Commercial Titan III (CT-III) rocket carrying the Skynet 4A and JCSAT-2 communications satellites. The second and third Commercial Titan III each launched one Intelsat VI communications satellite.
The first, Intelsat VI F-3, failed to separate from the carrier rocket. It was eventually freed by means of jettisoning its perigee motor, leaving it stranded in low Earth orbit. Space Shuttle Endeavour retrieved the spacecraft during the STS-49 mission – a task which required three astronauts to perform a spacewalk – and attached a replacement kick motor before sending the satellite on its way to geostationary orbit. Later renamed Intelsat 603, the spacecraft was only retired from service earlier in the year 2013.
Space Shuttle Endeavour retrieved and repaired Intelsat VI F-3 during STS-49
The most recent commercial geostationary launch from SLC-40 was in June 1990, when the third Commercial Titan III orbited Intelsat VI F-4. Unlike the previous Intelsat launch, this mission was successful.
One further CT-III launch was made from SLC-40, however it carried a NASA payload; the Mars Observer mission to the red planet in September 1992.
A third deorbit burn failed, so the Falcon 9 upper stage used to launch SES-8 was left behind in a decaying elliptical low-Earth orbit which, by September 2014, had decayed enough and re-entered the atmosphere.
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