SpaceX Falcon 9 Full Thrust - SES-9 - Launching March 4, 2016
Screenshot from SpaceX Webcast of the launch of SES-9
Mission Rundown: SpaceX Falcon 9 FT - SES-9
Written: January 31, 2021
How hard can water be?
SpaceX’s Falcon 9 rocket will deliver SES-9, a commercial communications satellite for SES, to a Geostationary Transfer Orbit (GTO).
SES S. A. is a world-leading satellite operator providing satellite-enabled communications services to broadcasters, Internet service providers, mobile and fixed network operators, and business and governmental organizations worldwide using its fleet of more than 50 geostationary satellites.
SpaceX is targeting an evening launch of SES-9 from Space Launch Complex 40 at Cape Canaveral Air Force Station, Florida. The approximately 90-minute launch window opens on March 4 at 11:35 pm UTC. The satellite will be deployed approximately 31 minutes after liftoff. If you want to know more, here’s another news source.
The Payload
SES-9 is a large communications satellite operating in geostationary orbit at 108.2° East, providing communications services to Northeast Asia, South Asia and Indonesia, maritime communications for vessels in the Indian Ocean and mobility beams for "seamless in-flight connectivity" for domestic Asian airlines of Indonesia and the Philippines.
The satellite was built by Boeing, using a model BSS-702HP satellite bus. 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 provides additional and replacement capacity for DTH broadcasting and data in Northeast Asia, South Asia and Indonesia, and maritime communications for the Indian Ocean. Broadcasts on six Ku-band coverage beams go to six different geographical areas in Asia.
SES-9 had a mass of approximately 5,271 kilograms (11,621 lb) at launch, the largest Falcon 9 payload yet to a highly-energetic geosynchronous transfer orbit (GTO). SES S.A. used the spacecraft's own propulsion capabilities to circularize the trajectory to a geostationary orbit.
SES-9 is a replacement for the NSS-11 satellite which was acquired by SES when it purchased GE Americom in 2001. Launched by a Proton-K/DM3 rocket in October 2000 with a design life of fifteen years, the satellite was initially named GE-1A, but following its acquisition by SES and the rebranding of GE Americom to SES Americom, it became Americom Asia-Pacific 1, or AAP-1.
The satellite was transferred to a new subsidiary, WorldSat, in January 2004 as WorldSat-1 and returned to SES Americom about a year later. In 2007, the satellite was transferred to another division, SES New Skies, as NSS-11. Following replacement by SES-9, NSS-11 will be relocated to a different orbital slot for further operation.
Risk Taking with Falcon 9
The original apogee for the transfer orbit contracted by SpaceX was 26,000 kilometers (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 kilometers (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.
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, 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 (a barge rebuilt as a floating landing platform) named Of Course I Still Love You.
Although SpaceX successfully recovered a first booster on land following the December launch to a less-energetic orbital trajectory, they had not yet succeeded in booster recovery from any of the previous attempts to land on a floating platform. 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.
As expected, booster recovery failed: the spent first stage "landed hard", damaging the drone ship, 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 from the launch site, were successful and returned significant test data on bringing back a high-energy and fast flying Falcon 9 from a launch on SLC-40 in Florida.
The word “high-energy” means that the kinetic energy stored in Falcon 9’s velocity squared and multiplied by the first stage mass, and that is reduced by the air’s friction cubed, which makes a Falcon 9 first stage return look like a burning freight train coming down.
Hot, heavy and fast.
