Screenshot from ULA Webcast of the Echostar-19 launch. Why do I feel like a ‘dead’ man walking
Mission Rundown: ULA - Atlas V 431 - Echostar-19
Written: December 26, 2022
Who owns the Cloud these days?
United Launch Alliance launched its last Atlas V rocket of the year 2016 on Sunday, December 18 with the mission of deploying the EchoStar XIX commercial communications satellite for Hughes Network Systems.
The Atlas V 431 launched at 14:13 EST - Eastern Standard Time (19:13 UTC) from Space Launch Complex 41 at the Cape Canaveral Air Force Station.
EchoStar XIX, also known as Jupiter 2, is a high-capacity communications satellite which will be used by Hughes Network Systems to provide broadband internet across North America from large servers to medium sized fiber optic network suppliers.
Hughes Network Systems (HNS), which became a subsidiary of EchoStar Corporation following a 2011 takeover, placed an order for the EchoStar XIX spacecraft in 2013 to provide additional capacity allowing it to take on additional subscribers. The company already operates the Spaceway-3 and EchoStar XVII satellites, while EchoStar itself has a large fleet of broadcasting satellites.
This mission was launched aboard an Atlas V 431 configuration vehicle, which includes a 4-meter extra extended payload fairing (XEPF) and three solid rocket boosters. The Atlas booster for this mission was powered by the RD AMROSS RD-180 engine, and the Centaur upper stage was powered by the Aerojet Rocketdyne RL10C engine.
The Echostar-19 Payload
The EchoStar XIX satellite was built by Space Systems/Loral and is based on the SSL-1300S bus. It carries multi-spot Ka-band transponders and is capable of producing over a hundred spot beams, providing bandwidth in excess of 150 gigabits per second. EchoStar has described the satellite as the world’s highest capacity broadband satellite.
The 6,637-kilogram (14,632 lb) EchoStar XIX satellite is powered by a pair of solar arrays, and is designed for a service life of at least fifteen years. The spacecraft will operate in geostationary orbit, at a longitude of 97.1 degrees west.
EchoStar XIX was intended for launch on Ariane, however in 2015 EchoStar announced a contract with Lockheed Martin to launch the satellite atop an Atlas V, citing a lack of available slots in Arianespace’s manifest and the need to ensure the satellite got into orbit as soon as it was ready to be launched.
EchoStar XIX was the fifth EchoStar spacecraft to launch on an Atlas, following EchoStars III, V and VI which launched on Atlas IIAS vehicles in 1997, 1999 and 2000, and EchoStar VII which launched on an Atlas IIIB in 2002.
The EchoStar XII satellite, which EchoStar acquired from CableVision on-orbit in 2005, was launched as Rainbow 1 on Atlas V’s third flight in July 2003.
The Atlas V rocket which launched EchoStar XIX is operated by United Launch Alliance (ULA), under contract through Lockheed Martin Commercial Launch Services.
ULA is contracted directly by US government customers for launch services, however Boeing and Lockheed Martin retained the right to market their former vehicles for commercial launches.
Only a small number of ULA’s launches have been commercial. These include launches of Atlas V rockets with the ICO-G1 (now EchoStar G1), Intelsat 14, Morelos 3 communications satellites and the WorldView-3 and 4 Earth-imaging satellites, and Delta II missions to deploy the WorldView-1 and 2 satellites, GeoEye-1 and COSMO-2, 3 and 4.
The Atlas V launches of the PAN and CLIO military satellites and Delta IV missions with NOAA’s GOES 14 and 15 weather satellites were technically flown under commercial contracts, despite their government payloads. Two Atlas V rockets launched Cygnus spacecraft for Orbital ATK, under NASA’s Commercial Resupply Services program.
The Atlas V 431 Launch
Sunday’s launch lasted a little over thirty-two minutes from liftoff to spacecraft separation, with the Centaur making two burns. The first stage engine, an NPO Energomash RD-180, ignited at the T-2.7 second mark in the countdown, with ignition of the solid rocket motors and liftoff of the vehicle following at T+1.1 seconds.
Atlas performed a series of pitch and yaw maneuvers to attain its planned launch trajectory, beginning five and a half seconds into the mission.
Flying downrange in an east-south-easterly direction, the rocket passed through Mach 1 – the speed of sound – 45.4 seconds after liftoff and experienced maximum dynamic pressure – Max-Q – 12.3 seconds later.
The three AJ-60A motors provided additional thrust during the first ninety seconds of the flight before burning out. The boosters remained attached until 125.1 seconds after liftoff, at which point two of the boosters separated from opposite sides of the vehicle, followed by the third one and a half second later.
First stage flight continued until Booster Engine Cutoff (BECO), the end of the RD-180’s burn, at four minutes and 26.7 seconds mission elapsed time. The spent Common Core Booster was jettisoned six seconds later, with Centaur igniting its RL10C-1 engine ten seconds after separation.
Eight seconds into the Centaur’s first burn, the payload fairing separated from around EchoStar XIX at the nose of the rocket. The fairing protects the satellite from Earth’s atmosphere during the early stages of the rocket’s ascent, however by the time the vehicle reaches space it is no longer needed and separates to save weight.
T+4 minutes, 51 seconds. Fairing separation is confirmed. The Atlas V now weighs 6% of its liftoff weight (28,720 kilograms compared to 478,665 kilograms).
The Atlas V can fly with a fairing which is either four or five meters in diameter – with the four-meter fairing mounted atop the Centaur and the five-meter fairing mounted above the first stage, encapsulating Centaur. AV-071 used a four-meter Extra-Extended Payload Fairing (XEPF), the longest of the three available four-meter fairings.
Centaur’s first burn lasted eight minutes and 55.9 seconds. Following shutdown, or Main Engine Cutoff 1 (MECO-1), the mission entered a nine-minute, 30.6-second coast phase. The coast ended with Main Engine Start 2 (MES-2), the beginning of the Centaur’s second and final burn, which lasted for five minutes and 48.4 seconds.
Ascent and flight profile of Echostar 19. 4-6 Orbit insertion burn. 7-8 GTO burn. 9 deployment.
With the second burn complete, Centaur reoriented itself for spacecraft separation. At 32 minutes and 3.7 seconds after launch, EchoStar XIX deployed into geosynchronous transfer orbit. The target orbit for Sunday’s mission is 204 by 65,000 kilometers (127 x 40,389 miles, 110 x 35,097 nautical miles), with inclination of 25.44 degrees to the equator and an argument of perigee of 180 degrees.
EchoStar 19/Jupiter 2 now on its way to circularize its geosynchronous transfer orbit to an altitude of 35,786 kilometers and reduce its inclination to 0 degrees.
The Atlas V 431 rocket
The Atlas V is a two-stage rocket consisting of a Common Core Booster (CCB) first stage and a Centaur second stage. The EchoStar XIX launch will fly in the 431 configuration, with a four-meter payload fairing, three Aerojet Rocketdyne AJ-60A solid rocket boosters augmenting the first stage, and the single-engine version of the Centaur.
The tail number of the rocket which conducted Sunday’s launch is AV-071.
AV-071 launched from Space Launch Complex 41 at the Cape Canaveral Air Force Station. Following assembly in the nearby Vertical Integration Facility, the Atlas was transported to the launch pad on Saturday.
The first stage, known as the Common Core Booster, contains 284,089 kilograms of both RP-1 kerosene and liquid oxygen. The second stage, known as the Centaur V1, contains 20,830 kilograms of both liquid hydrogen and liquid oxygen.
After fairing separation the Atlas V will weigh 6% of its liftoff weight - 478,665 kilograms. That’s Centaur 2nd stage plus EchoStar 19 that now weighs 28,720 kilograms.
At liftoff, the RD-180 engine and three AJ-60A boosters produce a combined sea level thrust of 1,877,357 pounds.
The Atlas V core RD-180 engine will provide 1,998,800 lbf of thrust, with each of the 3 solid rocket motors -AJ-60A- providing 379,600 lbf of thrust.
EchoStar 19/Jupiter 2 will be the third heaviest payload ever launched on an Atlas V rocket, weighing 6,637 kilograms.
The heaviest so far was Orbital ATK's Enhanced Cygnus spacecraft (7,492 kilograms) and the second heaviest was the United States Navy's MUOS satellite (6,740 kilograms).
At T+00: 06:15 - RL-10 is currently producing 22,886 pounds of thrust and burning fuel - cryogenic LH2+LOX - at the rate of 23.1 kilograms a second.
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