SES-8

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SES-8
Falcon 9 carrying SES-8 (08).jpg
The SpaceX Falcon 9 rocket carrying the SES-8 communications satellite launches from Cape Canaveral SLC-40.
Mission type Communication
Operator SES
COSPAR ID 2013-071A
SATCAT № 39460
Mission duration 15 years
Spacecraft properties
Bus Star-2.4
Manufacturer Orbital Sciences
Launch mass 3,170 kilograms (6,990 lb)
Power 5,000 watts
Start of mission
Launch date 3 December 2013, 22:41 (2013-12-03UTC22:41Z) UTC
Rocket Falcon 9 v1.1
Launch site Cape Canaveral SLC-40
Contractor SpaceX
Orbital parameters
Reference system Geocentric
Regime Geostationary
Longitude 95° East
Perigee 35,787 kilometres (22,237 mi)[1]
Apogee 35,798 kilometres (22,244 mi)[1]
Inclination 0.00 degrees[1]
Period 1436.11 minutes[1]
Epoch 25 October 2014, 13:50:28 UTC[1]
Transponders
Band 33 Ku-band

SES-8 is a geostationary communication satellite operated by SES. SES-8 was successfully launched on SpaceX Falcon 9 v1.1 on 3 December 2013, 22:41 UTC.[2]

It was the first flight of any SpaceX launch vehicle to a supersynchronous transfer orbit[3] an orbit with a somewhat larger apogee than the more usual Geostationary transfer orbit (GTO) typically utilized for communication satellites.[4]

Satellite[edit]

The SES-8 satellite is built on the GEOStar-2.4 satellite bus by Orbital Sciences.[5] It is the sixth satellite of that model to be built for SES.[6]

The commsat will be initially co-located at 95° East [7] 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."[6] [8]

Specifications[edit]

  • Payload mass: 3,200 kilograms (7,100 lb)[5][6]
  • Electrical power: 5 kW, using Gallium Arsenide solar panels, and two 4,850 watt-hours (17,500 kJ) lithium ion storage batteries[5][6]
  • Battery backup: 4800 Watt-hour lithium-ion battery[5]
  • Service life: 15 years[5][6]

Launch vehicle[edit]

The launch of Falcon 9 v1.1 with SES-8 from Cape Canaveral on 3 December 2013.

The launch of SES-8 was the seventh launch of the Falcon 9 launch vehicle, and the second launch of the Falcon 9 v1.1. SES is paying a discounted price—"well under US$60 million"—for the launch since it is the inaugural geostationary launch on the Falcon 9. When originally contracted, in 2011 the putative launch date was early 2013.[4]

The launch was the second launch of the Falcon 9 v1.1 version of the rocket, a longer rocket with 60 percent more thrust than version 1.0 Falcon 9 vehicle,[9] and will be the first launch of the larger v1.1 rocket using the rebuilt erector structure at SpaceX' Cape Canaveral launch pad.[5] As a result, a number of systems on the launch vehicle will be being flown for only the second time, while several parts of the ground infrastructure at Cape Canaveral were used in a launch for the first time. These include:[10]

  • second use of the upgraded Merlin 1D engines, generating approximately 56 percent more sea-level thrust than the Merlin 1C engines used on the first five Falcon 9 flights
  • second use of the significantly longer rocket stages, which were lengthened to accommodate the larger propellant tanks needed to carry propellant for the more powerful engines. The tanks are 60 percent longer, making the rocket more susceptible to bending during flight.[9]
  • the nine Merlin 1D engines on the first stage are arranged in an octagonal pattern with eight engines in a circle and the ninth in the center
  • second launch to have a jettisonable payload fairing, which has the risk of an additional separation event that has doomed many missions in the past. Fairing design was done by SpaceX, with production of the 13 m (43 ft) long, 5.2 m (17 ft)-diameter fairing done in Hawthorne, California at the SpaceX rocket factory. Testing of the new fairing design, first required on the CASSIOPE flight (the sixth flight of the Falcon 9), was done at NASA's Plum Brook Station where acoustic shock and mechanical vibration of launch, plus electromagnetc static discharge conditions, were tested on a full-size fairing test article in a very large vacuum chamber. SpaceX paid NASA US$581,296 to lease test time in the $150 million NASA simulation chamber facility.[11]
  • second flight of the vehicle with upgraded avionics and flight software.[9]

In order to maximize the propellant available for the launch of SES-8 into GTO, SpaceX did not attempt a controlled descent test of the first-stage booster as they did on the previous Falcon 9 v1.1 flight in September 2013.[12]

Second-stage reignition[edit]

In the previous launch of the Falcon 9 v1.1—the first launch of the much larger version of the rocket with new Merlin 1D engines—on 29 September 2013, SpaceX was unsuccessful in reigniting the second stage Merlin 1D vacuum engine once the rocket had deployed its primary payload (CASSIOPE) and all of its nanosat secondary payloads.[13] The restart failure was determined to be frozen igniter fluid lines in the second-stage Merlin 1D engine. A minor redesign was done to address the problem by adding additional insulation to the lines.[3]

A second burn of the upper stage was required, and was completed successfully, during the SES-8 mission[14] in order to place the SES-8 telecommunications satellite into the highly elipitical supersynchronous orbit for satellite operator SES to effect a plane change and orbit circularization.[3][13]

The Falcon 9 upper stage used to launch SES-8 was left in a decaying elliptical low-Earth orbit which, by September 2014, had decayed and re-entered the atmosphere.[15]

Prelaunch[edit]

Both stages of the Falcon 9 arrived at Cape Canaveral for processing before October 2, 2013, after both had trouble-free test firings at the SpaceX Rocket Development and Test Facility at McGregor, Texas.[6]

A launch attempt on 25 November 2013, with a planned liftoff at 22:37 UTC was scrubbed following a reported off-nominal condition in the liquid oxygen tank and supply lines of the first-stage booster that could not be resolved within the approximately one-hour launch window. A launch date of 28 November 2013 has been announced, three days later, being the next opportunity for the launch site on Earth to be in alignment to achieve the target orbit.

Launch attempts[edit]

Attempt Planned Result Turnaround Reason Decision point Weather go (%) Notes
1 25 November 2013 22:37 UTC !25 Nov 2013, 10:37:00 pm Hold and countdown restart --- Launch delay 25 November 2013 22:24 UTC !25 Nov 2013, 10:24 pm(T–0:13:00) 80% Launch window: 10:37–11:43 pm[16][full citation needed]
2 25 November 2013 22:54 UTC !25 Nov 2013, 10:54:00 pm Hold and countdown restart 0 days, 0 hours, 17 minutes Automatic abort 25 November 2013 22:47 UTC !25 Nov 2013, 10:47 pm(T–0:06:11) 80% Launch window: 10:37–11:43 pm[16]
3 25 November 2013 23:30 UTC !25 Nov 2013, 11:30:00 pm Scrubbed 0 days, 0 hours, 36 minutes Off-nominal condition 25 November 2013 23:26 UTC !25 Nov 2013, 11:26 pm(T–0:03:41) 80% Launch window: 10:37–11:43 pm[16]
4 28 November 2013 22:39 UTC !28 Nov 2013, 10:39:00 pm Hold and countdown restart 2 days, 23 hours, 9 minutes Automatic abort 28 November 2013 22:38 UTC !28 Nov 2013, 10:38 pm(T–0:00:30) 90% Launch window: 10:39–11:44 pm[16]
5 28 November 2013 23:44 UTC !28 Nov 2013, 11:44:00 pm Scrubbed 0 days, 1 hour, 5 minutes Data review not completed 28 November 2013 23:43 UTC !28 Nov 2013, 11:43 pm(T–0:00:48) 90% Launch window: 10:39–11:44 pm[16]
6 3 December 2013 22:41 UTC !3 Dec 2013, 10:41:00 pm Successful launch 4 days, 22 hours, 57 minutes 90% Launch window: 10:41 pm–00:07 am[16]

References[edit]

  1. ^ a b c d e "SES-8 Satellite details 2013-071A NORAD 39460". N2YO. 25 October 2014. Retrieved 26 October 2014. 
  2. ^ SatBeams: SES-8
  3. ^ a b c Svitak, Amy (2013-11-24). "Musk: Falcon 9 Will Capture Market Share". Aviation Week. Retrieved 2013-11-28. 
  4. ^ a b de Selding, Peter B. (2013-09-20). "Rocket Oversupply or Not, Satellite Operators Still Struggle To Secure Launches". Space News. Retrieved 2013-09-20. "The launch, for which SES paid well under $60 million, has suffered multiple delays as Hawthorne, Calif.-based SpaceX works through issues related to bringing the vehicle to operational status. Given the low price paid, SES is reluctant to move the satellite to another rocket despite the months-long delay. The company is still hoping for a launch in November or December. The original contract in 2011 called for an early 2013 launch." 
  5. ^ a b c d e f Graham, William (2013-12-03). "Falcon 9 v1.1 successfully lofts SES-8 in milestone launch". NASASpaceflight.com. Retrieved 2013-12-03. 
  6. ^ a b c d e f Bergin, Chris (2013-10-03). "SES-8 heads to Florida for next Falcon 9 v1.1 launch". NASAspaceflight.com. Retrieved 2013-10-02. 
  7. ^ "SES-8 on Gunter's Space Page". SES-8 on Gunter's Space Page. Retrieved 28 December 2013. 
  8. ^ "SES-8 on SES.com". SES-8 on SES.com. Retrieved 28 December 2013. 
  9. ^ a b c Klotz, Irene (2013-09-06). "Musk Says SpaceX Being "Extremely Paranoid" as It Readies for Falcon 9’s California Debut". Space News. Retrieved 2013-09-13. 
  10. ^ Foust, Jeff (2013-03-27). "After Dragon, SpaceX’s focus returns to Falcon". NewSpace Journal. Retrieved 2013-04-05. 
  11. ^ Mangels, John (2013-05-25). "NASA's Plum Brook Station tests rocket fairing for SpaceX". Cleveland Plain Dealer. Retrieved 2013-05-27. 
  12. ^ de Selding, Peter B. (2013-11-27). "Why the World’s 2nd Largest Satellite Fleet Operator Agreed To Be SpaceX’s 1st Customer for a Launch to Geo". Space News. Retrieved 2013-11-28. 
  13. ^ a b Ferster, Warren (2013-09-29). "Upgraded Falcon 9 Rocket Successfully Debuts from Vandenberg". Space News. Retrieved 2013-09-30. 
  14. ^ http://www.nasaspaceflight.com/2013/12/spacex-falcon-9-v1-1-milestone-ses-8-launch/
  15. ^ "FALCON 9 R/B details 2013-071B NORAD 39461". N2YO. Retrieved 2014-09-13. 
  16. ^ a b c d e f Mission Status Center