Europe’s giant Ariane 5 has triumphantly completed its fourth mission of 2013, blasting off with perfection from the ELA-3 (Ensemble de Lancement Ariane) complex at the Guiana Space Centre in Kourou, French Guiana, precisely on time at 5:30 p.m. local time (4:30 p.m. EDT) Thursday. The 171-foot-tall rocket delivered the Eutelsat 25B/Es’hail-1 and GSAT-7 communications satellites into orbit on behalf of the French-led European Telecommunications Satellite Organisation (EUTELSAT) and the Indian Space Research Organisation (ISRO). The two satellites weighed a total of 19,750 pounds and, together with the support equipment, today’s mission boosted a total of 21,300 pounds off the planet. Mission VA-215, as the mission was designated, is the 215th flight by Arianespace’s rocket family since the maiden voyage of Ariane 1 in December 1979. It is also the 71st mission by the Ariane 5, which made its first flight back in June 1996.
“On behalf of everybody at Arianespace, I would like to express our pride this evening in rising to the challenge of meeting the requirements of our three customers, Es’hailSat, EUTELSAT, and ISRO,” said Arianespace Chairman and CEO Stéphane Israël in a post-launch press release. Noting that this was Arianespace’s first mission in support of the Qatar-based Es’hailSat company, Israël continued: “I realize that this is a particularly important moment for Es’hailSat and for its CEO, Ali Ahmed al-Kuwari. EUTELSAT and ISRO are both long-standing partners to Arianespace, reaching back over 30 years, and they continue to entrust us with their satellites year after year, within the scope of partnerships that truly honor us.” Israël closed by extending thanks to key dignitaries at the Kourou launch site, who witnessed tonight’s liftoff. They included Nicole Bricq, France’s Minister of Foreign Trade, and Her Excellency Dr. Hessa al-Jaber, the Qatari Minister for Information and Communications Technology.
This year, 2013, has been a quite remarkable adventure for the venerable European booster. In February, an Ariane 5 lofted the Amazonas-3 and Azerspace-1/Africasat-1A payloads, followed by the Automated Transfer Vehicle (ATV)-4 “Albert Einstein” to the International Space Station in June and, most recently, the Alphasat and Insat-3D satellites last month. The VA-215 processing campaign has proceeded without incident at the South American facility, with the assembly of Ariane 5’s two stages and twin solid-fueled rocket boosters completed by 24 July in the Launcher Integration Building.
At about the same time, India’s GSAT-7 was deep into pre-flight checkout at Kourou “to confirm the multi-band satellite’s readiness with payloads in the UHF, S-band, C-band, and Ku-bands.” Developed by the Indian Space Research Organisation (ISRO)—whose attempt last week to test-launch its troubled Geostationary Satellite Launch Vehicle (GSLV) was scrubbed at T-2 hours—the 5,600-pound GSAT-7 arrived in French Guiana on 11 July and will spend nine years in geostationary orbit at 74 degrees East longitude. Also known as “Insat-4F,” it is a multi-band communications satellite, with a key aim to improve the coverage of telecom and direct-to-home broadcast services across the Indian subcontinent. GSAT-7 is also expected to support Indian defence forces, specifically the Indian Navy.
Also aboard Ariane 5 for the VA-215 mission was Eutelsat 25B/Es’hail-1, built by Space Systems Loral for EUTELSAT and the Qatar-based satellite company, Es’hailSat. According to EUTELSAT, the 13,200-pound satellite is expected “to respond to demand for the fastest-growing applications in the Middle East and North Africa, including video broadcasting, enterprise communications, and government services.” Eutelsat 25B/Es’hail-1 is equipped with four steerable, spot-beam antennas and four deployable reflectors, together with advanced command and telemetry capabilities, and is expected to support a 15-year operational lifespan in a 22,300-mile-high geostationary orbit. So named because it will reside at an operational location of 25.5 degrees East longitude, the satellite will cover North Africa, the Middle East, and Central Asia. It arrived at Kourou on 27 July for final processing.
For today’s launch, Eutelsat occupied the upper segment of the Ariane 5’s SYLDA (Système de Lancement Double Ariane) payload dispenser, with GSAT-7 sitting “beneath” it in the dual-satellite “stack.” On 9 August, the Ariane 5 was transferred from the 190-foot-tall Launcher Integration Building (BIL) to the 295-foot-tall Final Assembly Building (BAF), a move which marked the formal hand-over of the vehicle from prime industrial contractor Astrium Space Transportation to Arianespace. Concurrently, Eutelsat was moved to the S5 payload preparation center for fueling. A week later, on 16 August, GSAT-7 was installed in the lower deck of the SYLDA. Eutelsat took its place in the upper deck on 19 August. The final flight readiness review took place on Tuesday and, as expected, validated the “Go” status of the vehicle, its dual-satellite payload, the Guiana Space Centre’s infrastructure, and all downrange tracking and control assets. Rollout of the VA-215 stack to the ELA-3 launch zone took place yesterday (Wednesday).
With the giant rocket mounted atop one of two mobile launch tables, rollout required about 40 minutes and took place under perfect blue skies. Upon arrival at ELA-3 engineers will set to work establishing electrical, fluid, and other connections. Early on Thursday, final launch preparations will shift into high gear, with weather checks and authorization to begin loading 260,000 pounds of liquid oxygen and 50,000 pounds of liquid hydrogen into Ariane 5’s 100-foot-tall “cryotechnic main stage.” These propellants fed the booster’s French-built Vulcain-2 main engine, which produced 300,000 pounds of thrust at liftoff.
At T-4 minutes, the propellant tanks were pressurized for flight and Ariane transitioned to its internal power supplies. In the final seconds of the count, systems aboard the 1.7-million-pound rocket assumed primary control of all critical functions and the guidance system was unlocked to Flight Mode. With all stations describing their status as “Green” in the latter stages of the countdown, liftoff occurred precisely on the opening of today’s 50-minute “window.” Although the Vulcain-2 roared to life at T-0, liftoff itself did not occur for another 7.5 seconds, as a series of computer-executed engine-check operations were conducted, ahead of the command to fire the side-mounted solid boosters, each of which has a propulsive yield of around 1.4 million pounds at liftoff.
For the first five seconds of the ascent, the rocket rose vertically, after which the two computers inside the Vehicle Equipment Bay (VEB) initiated a pitch and roll program maneuver, actively rotating Ariane towards the east and establishing it onto the proper flight azimuth to insert its twin satellite cargoes into orbit. A minute into the ascent, Ariane 5 went supersonic and soon afterwards passed through “Max Q,” the period of maximum aerodynamic stress on the airframe.
At T+142 seconds, the twin boosters were jettisoned, heading for a parachute-assisted splashdown in the Atlantic Ocean, about 300 miles east of Kourou. Meanwhile, the rocket had by now reached a velocity of 1,250 mph and continued to climb under the impulse of the Vulcain-2 engine. Three and a half minutes after liftoff, the bullet-like payload fairing was jettisoned, exposing Eutelsat 25B/Es’hail-1 and GSAT-7 to the harsh space environment for the first time.
The Vulcain-2 shut down and the first stage was discarded about eight minutes and 53 seconds after launch, descending toward a splashdown zone off the coast of Africa, in the Gulf of Guinea. Meanwhile, the second stage—powered by a restartable, 6,100-pound-thrust Aestus engine—will ignite to pick up the baton for the final push into orbit. By now, the rocket will be over 105 miles high and traveling at more than 4,300 mph. Sixteen minutes later, having reached a velocity of 5,700 mph, Geostationary Transfer Orbit (GTO) will be attained. Eutelsat 25B/Es’hail-1 will depart the SYLDA at 5:58 p.m. local Kourou time (4:58 p.m. EDT), about 27 minutes and 45 seconds after launch. GSAT-7 followed at 6:04 p.m. local Kourou time (5:04 p.m. EDT), at 34 minutes and 26 seconds.
Today’s mission marked the 71st launch of an Ariane 5, which first flew back in June 1996. Weighing close to 1.7 million pounds, the rocket is one of the world’s most powerful launch vehicles and has supported dozens of missions, only four of which have been classified as total or partial failures. On its ill-fated maiden voyage, it succumbed to a software glitch and was remotely destroyed by the Flight Termination System when it began to veer off-course. Its second launch in October 1997 also failed, due to a premature shutdown of its core stage, whilst two others in July 2001 and December 2002 also underperformed. However, Ariane 5 has maintained unblemished record ever since. Key payloads delivered to space have included the Envisat environmental monitoring platform, the Artemis telecommunications satellite, the Rosetta cometary science mission, and four Automated Transfer Vehicles (ATVs) to the International Space Station.
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