SES-9

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SES-9
SES-9 (25200743545).jpg
SES-9 satellite encapsulated in the Falcon 9 payload fairing, but not yet mated with the launch vehicle, 20 February 2016.
Mission type Communications
Operator SES[1]
COSPAR ID 2016-013A
SATCAT no. 41380
Mission duration 15 years[1]
Spacecraft properties
Bus BSS-702HP[1]
Manufacturer Boeing[1]
Launch mass 5,271 kilograms (11,621 lb)[2]
Start of mission
Launch date 4 March 2016, 23:35
Rocket Falcon 9 Full Thrust
Launch site Cape Canaveral SLC-40
Contractor SpaceX
Orbital parameters
Reference system Geocentric[1]
Regime Geostationary[1]
Longitude 108.2° East[1]
Transponders
Bandwidth 81 ku transponders with frequency equivalent to 36 Mhz each

SES-9 is a geostationary communications satellite operated by SES S.A. It was launched from Cape Canaveral SLC-40 by a Falcon 9 Full Thrust rocket on 4 March 2016.

Satellite[edit]

SES-9 is a large communications satellite operating in geostationary orbit at the 108.2° East orbital slot, providing communications services to northeast Asia, South Asia and Indonesia, maritime communications for vessels in the Indian Ocean,[3] and mobility beams for "seamless in-flight connectivity" for domestic Asian airlines of Indonesia and the Philippines.[4]

The satellite was built by Boeing, using a model BSS-702HP satellite bus.[5]

SES-9 had a mass of approximately 5,271 kilograms (11,621 lb) at launch,[2] the largest Falcon 9 payload yet to a highly-energetic geosynchronous transfer orbit (GTO).[4] SES S.A. used the spacecraft's own propulsion capabilities to circularize the trajectory to a geostationary orbit.[6]

Market and coverage[edit]

SES-9 has 57 high-power Ku-band transponders, equivalent to 81 transponders of 36 MHz bandwidth and, co-located at 108.2°E alongside SES-7, it will provide additional and replacement capacity for DTH broadcasting and data in North east Asia, South Asia and Indonesia, and maritime communications for the Indian Ocean. Broadcasts are on six Ku-band coverage beams:[7]

  • South Asia Beam. Centred on India with a 55dBW signal (40cm dish) and taking in Pakistan, Bangladesh, Sri Lanka, Nepal, and parts of Myanmar.
  • North East Asia Beam. Centred on the Philippines with a 55dBW signal (40cm dish) and taking in the eastern seaboard of China and parts of Indonesia.
  • South East Asia Beam. Centred on Indonesia with a 54dBW signal (45cm dish) and taking in Malaysia, Singapore, and parts of Papua New Guinea.
  • West Indian Ocean Beam. Centred on the Gulf of Oman with a 53dBW signal (50cm dish) and taking in the Arabian Peninsula, East Africa, and the western coast of India and Pakistan.
  • East Indian Ocean Beam. Centred on the Bay of Bengal with a 54dBW signal (45cm dish) and taking in southern and eastern India, Sri Lanka, and parts of Bangladesh, Myanmar, Thailand and Malaysia.
  • Australia Beam. Centred on Adelaide in Australia with a 55dBW signal (40cm dish) and taking in South Australia and parts of Western Australia, Northern Territory (including Alice Springs), New South Wales and Victoria.

Launch operations[edit]

Contract and scheduling[edit]

In addition to the earlier SES-8 mission ordered in 2011 and launched in 2013, SES contracted SpaceX for three additional launches starting with SES-9, originally planned for 2015. The deal was announced on 12 September 2012.[8] In early 2015, SES announced[9] that it would be the launch customer of the next rocket evolution by SpaceX: Falcon 9 v1.1 Full Thrust (also called Falcon 9 v1.2,[10]and later, just Falcon 9 Full Thrust). At the time, SES expected SES-9 to be launched by September 2015.[11] Despite the failure of the CRS-7 mission in June 2015, SES re-confirmed in September 2015 their decision to provide the first payload for the new rocket variant; however the launch was postponed until late 2015.[12]

Eventually, after considering all options, SpaceX announced a change on 16 October 2015: Orbcomm's 11 OG2 satellites would be the payload on the return-to-flight mission of the redesigned rocket instead of SES-9.[11] The Orbcomm payload with its lower orbit would allow SpaceX to test relighting the second-stage engine, a capability required to successfully put the heavier SES-9 on a geostationary orbit.[11] The Orbcomm mission was subsequently delayed to mid-December, while SES-9 was scheduled to follow "within a few weeks".[11] Finally, Falcon 9 Full Thrust performed its maiden launch on 22 December 2015, the final launch of the Falcon 9 v1.1 variant followed in January 2016, with SES-9 moving to February. Consequently, this was the second launch of the Full Thrust variant.[5]

Launch attempts[edit]

A successful static fire test of the rocket was completed on 22 February 2016.[5]

Flight 22 on 24 February 2016 launch attempt, which was scrubbed prior to loading propellants.
Attempt Planned Result Turnaround Reason Decision point Weather go (%) Notes
1 24 Feb 2016, 11:46:00 pm Delayed [13] Issue loading cryogenic liquid oxygen[13] 60%
2 25 Feb 2016, 11:47:00 pm Aborted [14] 1 day, 0 hours, 1 minute Issue loading cryogenic liquid oxygen[14]  (T-00:01:41[14]) 80%[13]
3 28 Feb 2016, 11:47:00 pm Aborted [15] 3 days, 0 hours, 0 minutes Fouled Range[15] 95%
4 29 Feb 2016, 12:21:00 am Aborted [15] 0 days, 0 hours, 34 minutes Low thrust alarm due to rising oxygen temps[15] 95%
5 4 Mar 2016, 11:35:00 pm Successful launch [16] 4 days, 23 hours, 14 minutes 90% Launch window: 23:35 to 01:06 UTC

The launch was initially scheduled for 24 February 2016 at 6:46pm local time, with a backup launch window the next day at the same time.[4] Neither day produced a launch however as both attempts were scrubbed: on 24 February, prior to propellant loading "out of an abundance of caution, in order to get the rocket’s liquid oxygen propellant as cold as possible"; and on 25 February, just two minutes prior to launch “citing a last-minute problem with propellant loading.”[17]

Subsequently the launch was rescheduled for the evening of Sunday 28 February at 6:46pm EST (23:46 UTC), with a fallback slot same time next day.[18] The first Sunday launch attempt was aborted less than two minutes before scheduled liftoff due to a tugboat entering the area of the offshore safety zone.[19] A second attempt on 28 February was made about 35 minutes later, after the downrange zone had been cleared, however, the rocket shut-down a moment after ignition due to low thrust flag from one engine. Rising oxygen temperature due to the hold for the tugboat to clear and a suspected helium bubble were suggested by Elon Musk as the likely reasons for the alarm being triggered.[20] The next launch attempt on March 1st was postponed to March 4th due to high winds.[21]

Falcon 9 Flight 22 launching on 4 March 2016, carrying SES-9

The launch was finally attempted, and succeeded, on 4 March 2016 at 23:35 UTC (6:35 pm local time).[6]

Orbit adjustment[edit]

The original apogee for the transfer orbit contracted by SpaceX was 26,000 km (16,000 mi), a subsynchronous highly-elliptical orbit that SES would then circularize and raise over several months before the satellite would be ready for operational service at 36,000 km (22,000 mi). SES CTO Martin Halliwell indicated in February 2016 that SpaceX had agreed to add additional energy to the spacecraft with the launch vehicle and that a new apogee of approximately 39,000 km (24,000 mi) was the objective, in order to assist SES in the satellite becoming operational many weeks earlier than otherwise possible, in part to help compensate for the schedule delays leading up to the launch. This was to be achieved by the second stage burning to depletion, instead of stopping at a target velocity.[2] SpaceX said they were projecting an apogee of at least 38,000 km (24,000 mi). In the event, the actual apogee achieved was approximately 40,600 km (25,200 mi), significantly reducing the estimated time for the satellite to become fully operational on station.

Post-mission landing test[edit]

External video
SES-9 Technical Webcast: Experimental Landing

Following word from SES that SpaceX had allocated some of the normal propellant reserve margins for landing to placing the SES-9 satellite in a higher (and more energetic) orbit than originally planned,[22] SpaceX confirmed in February that they would still attempt a secondary goal of executing a controlled-descent and vertical landing flight test of the first stage on the SpaceX east-coast Autonomous spaceport drone ship (floating landing platform) named Of Course I Still Love You.[5][23][4] Although SpaceX successfully recovered a first booster on land following the December launch to a less-energetic orbital trajectory,[24][25] they had not yet succeeded in booster recovery from any of the previous attempts to land on a floating platform.[23] Because the SES-9 satellite was very heavy and was going to such a high orbit, SpaceX indicated prior to launch that they did not expect this landing to succeed.[22]

As expected, booster recovery failed: the spent first stage "landed hard", damaging the drone ship,[26] but the controlled-descent and atmospheric re-entry, as well as navigation to a point in the Atlantic ocean over 600 kilometers (370 mi) away[27] from the launch site, were successful and returned significant test data on bringing back a high-energy Falcon 9.[6]

The controlled descent through the atmosphere and landing attempt for each booster is an arrangement that is not used on other orbital launch vehicles.[28] SES CTO Martin Halliwell had informed SpaceX that they were willing to use the same rocket twice to power another satellite to orbit.[29] This idea became reality in March 2017 with the SES-10 mission flying with the reused booster from CRS-8.

By March 21, 2016, the hole in the deck of the drone ship had been nearly repaired.[30]

See also[edit]

References[edit]

  1. ^ a b c d e f g "SatBeams - Satellite Details - SES-9". SatBeams. Retrieved 2016-02-29. 
  2. ^ a b c Clark, Stephen (2016-02-24). "Falcon 9 rocket to give SES 9 telecom satellite an extra boost". Spaceflight Now. Retrieved 2016-03-07. SES 9’s launch weight is 11,620 pounds, or about 5,271 kilograms, [...] heavier than the Falcon 9 rocket’s advertised lift capacity to geosynchronous transfer orbit, an elliptical path around Earth that serves as a drop-off point for communications satellites heading for positions 22,300 miles (36,000 kilometres) above the equator, a popular location for powerful broadcast platforms. Geosynchronous transfer orbits targeted by satellite launchers typically have an apogee, or high point, of at least 22,300 miles and a low point a few hundred miles above Earth. [...] SES’s contract with SpaceX called for the rocket to deploy SES 9 into a “sub-synchronous” transfer orbit with an apogee around 16,155 miles (26,000 kilometres) in altitude. Such an orbit would require SES 9 to consume its own fuel to reach a circular 22,300-mile-high perch, a trek that Halliwell said was supposed to last 93 days. The change in the Falcon 9’s launch profile [is planned to] put SES 9 into an initial orbit with an apogee approximately 24,419 miles (39,300 kilometres) above Earth, a low point 180 miles (290 kilometres) up, and a track tilted about 28 degrees to the equator. 
  3. ^ "SES-9". SES. 2016-02-23. Archived from the original on 2016-02-21. Retrieved 2016-02-23. 
  4. ^ a b c d "SES-9 Mission" (PDF). Press Kit. SpaceX. 2016-02-23. Retrieved 2016-02-24. This mission is going to a Geostationary Transfer Orbit. Following stage separation, the first stage of the Falcon 9 will attempt an experimental landing on the “Of Course I Still Love You” droneship. Given this mission’s unique GTO profile, a successful landing is not expected. 
  5. ^ a b c d Bergin, Chris (2016-02-22). "SpaceX Falcon 9 conducts Static Fire ahead of SES-9 launch". NASASpaceFlight.com. Archived from the original on 2016-02-22. Retrieved 2016-02-22. 
  6. ^ a b c Foust, Jeff (2016-03-04). "SpaceX launches SES-9 satellite". SpaceNews. Retrieved 2016-03-05. After a variety of problems delayed four previous launch attempts, a SpaceX Falcon 9 successfully launched the SES-9 communications satellite March 4, although an attempted landing of the rocket’s first stage on a ship was not successful, as expected. 
  7. ^ SES-9 fact sheet SES. Accessed March 30, 2016
  8. ^ Nelson, Katherine; Felte, Yves (2012-09-12). "SES and SpaceX announce contract for three satellite launches" (Press release). SpaceX. Retrieved 2016-02-27. 
  9. ^ Clark, Stephen (February 20, 2015). "SES signs up for launch with more powerful Falcon 9 engines". Spaceflight Now. Retrieved May 8, 2015. 
  10. ^ Svitak, Amy (17 March 2015). "SpaceX's New Spin on Falcon 9". Aviation Week. Aviation Week Network. Retrieved 24 October 2015. 
  11. ^ a b c d de Selding, Peter B. (October 16, 2015). "SpaceX Changes its Falcon 9 Return-to-flight Plans". SpaceNews. Retrieved October 16, 2015. 
  12. ^ Foust, Jeff (September 15, 2015). "SES Betting on SpaceX, Falcon 9 Upgrade as Debut Approaches". SpaceNews. Retrieved September 19, 2015. 
  13. ^ a b c Clark, Stephen (2016-02-25). "Commercial Falcon 9 launch delayed to Thursday". Spaceflight Now. Retrieved 2016-02-29. 
  14. ^ a b c Clark, Stephen. "SpaceX launch aborted in final minutes". Spaceflight Now. Retrieved 2016-02-29. 
  15. ^ a b c d Clark, Stephen. "Falcon 9 grounded again after last-second abort". Spaceflight Now. Retrieved 2016-02-29. 
  16. ^ @SpaceX (2016-03-04). "Liftoff!" (Tweet) – via Twitter. 
  17. ^ Foust, Jeff (2016-02-25). "SpaceX scrubs SES-9 launch again". SpaceNews. Retrieved 2016-02-26. 
  18. ^ @SES_Satellites (February 27, 2016). "SES and SpaceX are now targeting to launch #SES9 on Sunday, 28 February, at 6.46pm ET, with a backup date on Monday, 29 February!" (Tweet) – via Twitter. 
  19. ^ http://www.floridatoday.com/story/news/local/2016/02/29/tug-boat-contributed-spacex-launch-scrub/81102952/
  20. ^ Elon Musk [@elonmusk] (February 28, 2016). "Launch aborted on low thrust alarm. Rising oxygen temps due to hold for boat and helium bubble triggered alarm" (Tweet) – via Twitter. 
  21. ^ Elon Musk [@elonmusk] (2016-03-01). "Pushing launch to Friday due to extreme high altitude wind shear. Hits like a sledgehammer when going up supersonic" (Tweet) – via Twitter. 
  22. ^ a b Grush, Loren (2016-02-23). "SpaceX doesn't expect a successful landing after its rocket launch tomorrow". The Verge. Retrieved 2016-02-23. 
  23. ^ a b Orwig, Jessica (2016-02-23). "SpaceX will attempt a potentially historic rocket landing this week — here's how to watch live". Business Insider. Retrieved 2016-02-23. 
  24. ^ "SpaceX ORBCOMM-2 Mission" (PDF). press kit. SpaceX. December 21, 2015. Retrieved December 21, 2015. This mission also marks SpaceX’s return-to-flight as well as its first attempt to land a first stage on land. The landing of the first stage is a secondary test objective. 
  25. ^ Gebhardt, Chris (31 December 2015). "Year In Review, Part 4: SpaceX and Orbital ATK recover and succeed in 2015". NASASpaceFlight.com. Retrieved 1 January 2016. 
  26. ^ Elon Musk [@elonmusk] (2016-03-05). "Rocket landed hard on the droneship. Didn't expect this one to work (v hot reentry), but next flight has a good chance" (Tweet) – via Twitter. 
  27. ^ SpaceX (4 March 2016). SES-9 Full Webcast. 19:58 minutes in. Retrieved 31 March 2017 – via YouTube. 
  28. ^ "SpaceX wants to land next booster at Cape Canaveral". Florida Today. December 1, 2015. Retrieved December 4, 2015. 
  29. ^ Klotz, Irene (2016-02-23). "Satellite operator SES says interested in used SpaceX rocket". Reuters. Retrieved 2016-02-24. 
  30. ^ Tim Dodd Photography (22 March 2016). ASDS March 21, 2016 (OCISLY). Retrieved 31 March 2017 – via YouTube. 

External links[edit]