Arianespace\u2019s Soyuz ST-B rocket has launched the first satellites that will act as pathfinders to a huge satellite constellation for OneWeb that is aimed at providing full global internet coverage. The launch took place at the opening of the window at 21:37 UTC from the European Spaceport in French Guiana.<\/p>\n
The Flight VS21 marks the 21st liftoff of Soyuz from French Guiana since this medium-lift launcher\u2019s 2011 operational debut at the Spaceport.<\/p>\n
The rocket has suffered delays in the path to this launch, first with the discovery of a pinhole in the Fregat upper stage that has since been repaired. Then, a small slip occurred as Russian officials checked for commonality with the problem suffered by a Soyuz 2-1b launch of EgyptSat-A that successfully deployed the satellite but had problems during third stage flight.<\/p>\n
\u201cBased on the positive results of analyses performed with Russian space authorities responsible for a Soyuz launch, Arianespace has taken the decision to resume preparations for its Flight VS21 OneWeb F6 mission at the Guiana Space Center,\u201d Arianespace confirmed, as it gave the green light for the launch to take place.<\/p>\n
The Soyuz ST-B is based on the Soyuz-2-1b rocket, incorporating modifications specific to using Arianespace\u2019s launch site, the Centre Spatial Guyanais (CSG), located near Kourou in French Guiana. Soyuz-2-1b is itself one of three modernized versions of earlier Soyuz rockets, derivatives of Sergei Korolev\u2019s R-7 missile that have been used for Russian (and formerly Soviet) satellite and crewed spaceflight launches since the 1960s.<\/p>\n
Soyuz is a three-stage rocket, although the first and second stages fire together at liftoff. To reach higher orbits or perform more complex missions, Soyuz can be used in conjunction with an upper stage. For this mission a Fregat-M was used to insert the satellites into orbit.<\/p>\n
Fregat is the most common type of upper stage flown on Soyuz; it is based on the propulsion systems of the Soviet Union\u2019s late interplanetary probes and can restart its engine multiple times over a lengthy extended mission to ensure delivery of its payload into the required orbit.<\/p>\n
The Soyuz launch pad, Ensemble de Lancement Soyouz (ELS), was first used in October 2011 for the deployment of a pair of Galileo navigation satellites. Including the vehicle that is performing this mission, seven Soyuz ST-A and fourteen Soyuz ST-B rockets have departed Kourou. All but one of the Soyuz launched from Kourou \u2013 a Soyuz ST-B whose Fregat upper stage malfunctioned \u2013 have completed their missions successfully.<\/p>\n
The Fregat placed the satellites into a near-polar orbit, with the OneWeb spacecraft operating at an altitude of 1,200 km., giving customers extremely low latency and providing communications access to the entire world with fiber-quality internet connectivity. They will operate in 18 planes of 40 satellites each, with an inclination of 87.9 degrees relative to the equator.<\/p>\n
Space Shuttle models (adsbygoogle = window.adsbygoogle || []).push({});<\/p>\n The mission duration from launch to end of mission was just over 82 minutes.<\/p>\n<\/p>\n