|HARD / TELECOMS / Wednesday, 05 January 2011 12:47|
This evening, an Ariane 5 launcher lifted off from Europe’s Spaceport on a journey to place two telecommunications satellites, Hispasat-1E and Koreasat-6, into their planned transfer orbits. Flight V199 was the sixth Ariane 5 launch of 2010 and the last of the year.
Liftoff of the 55th Ariane 5 mission came at 22:27 CET (21:27 GMT; 18:27 French Guiana). The target injection orbit had a perigee altitude of 250 km, an apogee altitude at injection of 35 786 km and an inclination of 3º.
The satellites were accurately injected into their transfer orbits about 27 minutes and 34 minutes after liftoff, respectively.
Hispasat-1E will be positioned in ‘geostationary orbit’ above the equator at 30ºW. It will provide direct-to-home television, digital terrestrial television and high-definition television services, as well as value-added broadband services to mobile, land and maritime users.
Koreasat-6, to be positioned over 116ºE, carries 24 Ku-band channels to provide Fixed Satellite Services and six channels for Direct Broadcast Services.
Satellites in a circular orbit over the Equator at an altitude of 35 800 km keep pace with Earth’s rotation and appear stationary when observed from Earth, hence 'geostationary'.
Ariane 5 flight V199 liftoff
V199 flight timeline
The Ariane 5’s cryogenic, liquid-propellant main engine was ignited first. Seven seconds later, the solid-propellant boosters were also fired, and the vehicle lifted off a fraction of a second later.
The solid boosters were jettisoned 2 min 20 sec after main engine ignition, and the fairing protecting the payload during the climb through Earth’s atmosphere was discarded at 3 min 9 sec. The launcher’s main engine was shut down at 8 min 55 sec; six seconds later, the main cryogenic stage separated from the upper stage and its payload.
Four seconds after main stage separation, the engine of the cryogenic upper stage was ignited to continue the journey. The engine was shut down at 25 min 2 sec into the flight, at which point the vehicle was travelling at 9359 m/s (33 692 km/h) at an altitude of 642 km. The conditions for geostationary transfer orbit injection had been achieved.At 27 min 27 sec after main engine ignition, Hispasat-1E separated from the upper stage, followed by Koreasat-6 at 34 min 12 sec. Ariane 5’s flight operations were completed 47 min 34 sec after main engine ignition.
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|Last Updated on Wednesday, 05 January 2011 12:51|