SES-8

Spacecraft nº:

Netherlands spacecraft nº: 13

Launch data: Designation  39460 / 13071A Launch date  03 Dec 2013 - 22:41 UT Launch site  CC, SLC-40 Launch vehicle  Falcon-9 v1.1 Mission  Communication Earth orbit: Perigee / Apogee  35668 x 45307 km Eccentricity   Inclination  0.5 deg Period  1683.0 min

Spacecraft data:

Description:

• A SpaceX Falcon 9 rocket will launch the SES 8 communications satellite. SES 8 will provide Ku-band and Ka-band direct-to-home broadcasting and network services over the Asia-Pacific region. The rocket will fly in the Falcon 9 v1.1 configuration with upgraded Merlin 1D engines, stretched fuel tanks, and a payload fairing.
• SES 8 is built by Orbital Sciences Corp. and carries Ku-band and Ka-band transponders to broadcast direct-to-home television to customers across India, Vietnam, Thailand and neighboring countries. The satellite launch is a key turning point in SpaceX's 11-year history, proving the company is capable of tackling more challenging launch missions, such as deploying communications satellites, military payloads and interplanetary probes.
• SES-8 will feature 33 high-power Ku-band (36 MHz-equivalent) transponders and will be co-positioned with the NSS-6 satellite at the orbital location of 95° East. SES-8 is a medium-sized satellite with beams focused on South Asia (India) and Indo-China (Thailand, Vietnam, Laos) to support existing DTH customers with back-up and growth transponder capacity. The spacecraft will be built on Orbital’s flight-proven STAR spacecraft platform and will generate approximately 5.0 kilowatts of payload power.

Mission details:

• Launch delayed from July, Aug and Sep 2013.
• On Monday, 25 November 2013, the opening launch attempt was halted at T-13 minutes, due to a technical issue with a first-stage liquid oxygen vent valve, prompting SpaceX to recycle the clock for a revised T-0 later in the 66-minute “window” as engineers scrambled to formulate a troubleshooting plan. A second countdown ticked down to T-6 minutes and 11 seconds, just shy of Autosequence Start, when the clock stopped again, due to a problem with the transition to first-stage internal power. Barely enough time remained in the window for another recycle, but SpaceX marched toward yet another revised T-0 time, but was eventually thwarted by a first-stage issue which halted the clock at T-3 minutes and 40 seconds. From that point, insufficient time remained in Monday’s window to attempt another recycle and the launch was scrubbed.
• The second effort to get the Falcon 9 v1.1 airborne on Thursday, 28 November, demonstrated nothing less than the myriad safety systems of the two-stage booster in action. This time, the countdown ran with near-perfection, and with a seemingly flawless vehicle and exceptional weather conditions at the Cape, the command was issued to ignite the nine Merlin-1D engines at T-3 seconds. Carefully monitored by the flight computers, it soon became apparent that the thrust build-up of the engines’ chamber pressures did not meet required levels and an automatic shutdown was called, after the ignition sequence had started. The roar of rocket exhaust quickly died. Although the countdown clock read T+2 seconds, the hold-down clamps had not yet been commanded to release the Falcon from the SLC-40 pad surface. “This demonstrated the value of SpaceX’s hold-before-release system,” noted SpaceX’s Falcon 9 Product Director John Insprukter earlier tonight (Tuesday). “Thursday’s abort was caused by oxygen in the ground-side igniter fluid,” SpaceX explained. “Rocket engines are healthy, but cleaning turbopump gas generators will take another day".
• The 3e launch effort was on 03 Dec. Autosequence Start occurred at T-6 minutes, with the rocket’s propellant tanks verified to be at the proper flight pressures, and the launch pad’s “strongback” was completely retracted by T-4 minutes. The Flight Termination System (FTS)—tasked with destroying the Falcon in the event of a major accident during ascent—was placed onto internal power and armed, and by T-2 minutes and 15 seconds the first stage was confirmed to be at pressure.
  At T-1 minute, the flight computer was confirmed to be in control of the vehicle, with the second-stage tanks pressing to flight pressures. SLC-40?s “Niagara” deluge system began to flood the pad surface with 30,000 gallons (113,500 liters) of water per minute to suppress acoustic waves radiating from the Merlin-1D exhaust plumes. At T-45 seconds, all tanks were confirmed to be at flight pressure. The vehicle’s propellant tanks were pressurized and at T-3 seconds the nine Merlin-1D engines roared perfectly to life. Unlike Thursday’s abort, all nine ramped up perfectly to their required parameters, and at 5:41 p.m. EST the second mission of the Falcon 9 v1.1 officially got underway with a spectacular roar.
  At the instant of liftoff, the nine first-stage engines generated 1.3 million pounds (590,000 kg) of thrust, about 200,000 pounds (90,000 kg) greater than the Falcon 9 v1.0, and pushed the vehicle uphill for 180 seconds. Their propulsive yield gradually rose to 1.5 million pounds (680,000 kg) in the rarefied high atmosphere. “Unlike airplanes, a rocket’s thrust actually increases with altitude,” noted SpaceX. “Falcon 9 generates 1.3 million pounds of thrust at sea level, but gets up to 1.5 million pounds of thrust in the vacuum of space. The first-stage engines are gradually throttled near the end of first-stage flight to limit launch vehicle acceleration as the rocket’s mass decelerates with the burning of fuel.”
• Immediately after clearing the SLC-40 tower, the Falcon 9 v1.1 executed a combined pitch, roll, and yaw program maneuver to establish itself onto the proper flight azimuth for the injection of the SES-8 communications satellite into geostationary transfer orbit. Eighty seconds into the ascent, the vehicle passed Mach 1 and experienced a period of maximum aerodynamic stress (known as “Max Q”) on its airframe. The Merlin-1Ds continued to burn hot and hard, finally shutting down at T+2 minutes and 58 seconds, and the first stage was jettisoned five seconds later. The turn then came for two “burns” by the Falcon’s restartable second stage, which ignited for the first time at T+3 minutes and 10 seconds. Its single Merlin-1D Vacuum engine, with a maximum thrust of 180,000 pounds (81,600 kg), burned for 320 seconds to establish the vehicle and SES-8 payload into a “parking” orbit.
• After reaching parking orbit the second stage reignited at 2308 UTC and placed SES-8 in a 423 x 79977 km x 20.47 deg supersynchronous transfer orbit. SpaceX does not appear to have released the parameters of the parking orbit but it appears to have been around 300 x 400 km x 28.5 deg.
• Around 1545 UTC on Dec 5 SES-8 reached first apogee and raised its orbit to 14401 x 80416 km x 6.2 deg, and then the next day to 35823 x 79932 km x 1.2 deg. Apogee was then lowered on Dec 11 and the orbit is now 35681 x 45299 km x 0.5 deg, with a further apogee lowering burn needed to reach GEO once the spacecraft is in the right spot.

Satellite tracking: