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Europe's Vega launch vehicle The development of the light-weight Vega booster was funded by the European Space Agency, ESA, to give the continent a share of the small satellite launch market previously dominated by Russian rockets converted from ballistic missiles. The rocket was intended primarily for launching scientific and Earth-observation satellite with polar and Sun-synchronous orbits as the most frequent destination. Although Vega's three solid-propellant booster stages were developed in Europe, its forth stage engine was subcontracted to KB Yuzhnoe in the former Soviet republic of Ukraine thus linking the program to the Soviet engineering heritage.
Vega space launcher and its major components. Copyright © 2012 Anatoly Zak / RussianSpaceWeb.com Origin of the program The Vega project was conceived in Italy in 1988, when a US-built Scout launcher carrying Italian satellites from a floating platform off the coast of Kenya was retired. (551) To replace it, the Italian firm BPD Difesa Spazio proposed to the newly formed Italian Space Agency, ASI, a domestically built rocket. The new vehicle would be based on the Zefiro motor developed by the company for the European Ariane program. By the early 1990s, the industry studied the possibility of complementing the Ariane family with a small launch vehicle using Ariane's solid booster technology. The project became known as the Vettore Europeo di Generazione Avanzata, or simply Vega. After about ten years of definition and consolidation research, the Italian Space Agency and the Italian industry proposed Vega as a European project. It would be based on the Italian know-how in solid propulsion inherited from the development and production of solid strap-on boosters, PAP, for the Ariane-4 rocket and from the components of Ariane 5's strap-on boosters, EAP. In April 1998, ESA's governing council approved a resolution authorizing pre-development activity. As a result, a configuration was chosen with the first stage that could potentially double as an improved strap-on for the Ariane-5 launcher. On November 27-28 ESA's Ariane Programme Board approved the Vega project and its development officially started on 15 December 2000, when seven countries subscribed to the agency's declaration. Along with Italy, other ESA members -- Belgium, the Netherlands, Spain, Sweden, Switzerland and France agreed to fund the program. (547) Thanks to the extensive use of existing technologies, the Vega was to be a low-cost and highly reliable rocket. Program organization Upon approval of the Vega development, Italian Space Agency, ASI, and an industrial firm Fiat Avio formed a joint venture ELV S.p.A in December 2000 to serve as a prime contractor in the project. The organization would use its experience in the development of solid boosters for the Ariane family of rockets. Other contractors included Europropulsion, SNECMA, Stork Product Engineering, EADS CASA, EADS ST, SABCA, Dutch Space, Contraves, KB Yuzhnoe. A responsibility for the marketing, sales, mission management and launch services of the operational Vega vehicle and its derivatives were given to the main European launch operator - Arianespace. Along with Ariane and Soyuz family of rockets, Vega would be based at the Kourou launch facility in French Guiana, South America. The original space launch pad at the equatorial site, which was previously used for Europa, Ariane-1, Ariane-2 and Ariane-3 rockets, was refurbished for Vega. Technical description Vega was designed to carry up to 1,500 kilograms of payloads to a 700-kilometer circular polar orbit. The rocket consisted of three booster stages burning solid propellant and an liquid-propellant forth stage known as Attitude and Vernier Upper Module or AVUM. All three booster stages consist of solid-propellant charges encased into a carbon-epoxy filament. To steer the rocket in flight, the main nozzle on each motor can be gimbaled from six to seven degrees with the help of a pair of electric actuators. After completing their burns, lower two stages would fire small thrusters opposite to the direction of flight to separate from the next stage. On the third stage, flying in vacuum of space, it would be enough to use springs for the same purpose. The upper stage would be topped with a protective payload fairing. The use of liquid propellant on the AVUM upper stage allowed to fire and shut down its Ukrainian-built engine up to five times, thus giving Vega great maneuvering flexibility in reaching various orbits. The orbital tug would also allow to properly orient its payload prior to its release. Two clusters of three small engines using nitrogen gas from a single 87-liter tank would be used for attitude control during the operation of the third and fourth stage. After releasing its cargo, the AVUM stage would fire its main engine for the last time to safely deorbit itself. According to the original plans, the manufacturer could provide at least four vehicles per year. Ukrainian engine mystery The liquid-propellant engine on the Vega's fourth stage uses hypergolic (storable) propellant fed under pressure from four 142-liter titanium tanks. Helium gas stored under 35.6 bars of pressure in a special tank is used to push propellant into the engine. According to the official Ukrainian publications, the design of the Vega's engine was based on components of existing mass-produced propulsion systems. (548) When the Ukrainian space industry started showcasing its new engine at international shows, it was identified simply as Vega main engine. No exact designation or details on its engineering heritage was provided. In European documents, the engine was identified as RD-869, even though Russian sources linked this name to a Soviet-era ICBM. By 2011, an official Ukrainian publication identified the engine as RD-843. Launch preparations From 2002 until 2004, Vega's first mission was promised in 2006. (550) However by 2005, the first launch was delayed until 2007 and by December 2006 and it was not expected before the end of 2007. (549) In the spring of 2008, officials in charge of the ELA-1 launch site reconstruction promised Vega's first launch with a dummy satellite in mid-2009. By September of the same year, the launch slipped to November 2009. The first Vega rocket finally arrived to Kourou on October 25, 2011, in preparation for its first mission then scheduled for Jan. 26, 2012, and designated VV01. When the assembly of the vehicle was completed on January 26, its launch was expected on February 9, 2012. On February 3, Arianespace announced that Vega would fly on February 13, 2012. Vega flies its first test mission A brand-new European launcher started a maiden voyage into the Earth orbit from South America Monday, Feb. 13, 2012. A light-weight Vega rocket incorporating a Ukrainian propulsion system lifted off as scheduled from the original space launch pad in Kourou, French Guiana, at 7 a.m. local time (5 a.m. EST, 10:00 GMT). Some 55 minutes after the liftoff, ESA confirmed a successful separation of the LARES satellite, declaring the primary mission of the Vega launcher a success. The development of the light-weight Vega booster was funded by the European Space Agency, ESA, to give the continent a share of the small satellite launch market previously dominated by Russian rockets converted from ballistic missiles. The rocket was intended primarily for launching scientific and Earth-observation satellite with polar and Sun-synchronous orbits as the most frequent destination. Although Vega's three solid-propellant booster stages were developed in Europe, its forth stage engine was subcontracted to KB Yuzhnoe in the former Soviet republic of Ukraine thus linking the program to the Soviet technological heritage. The first mission In its first launch Vega was to carry the 390-kilogram LAser RElativity Satellite, LARES, for the Italian Space Agency as its primary payload and nine tiny secondary satellites known as cubesats. LARES would be released first from the AVUM upper stage into a 1,450-kilometer orbit with an inclination 70-degrees toward the Equator. A spherical satellite carried 92 reflectors for high-precision laser experiments. LARES built on the experience of two Italian-American geodetic missions (Lageos-1 and Lageos-2), and aims to improve measurements of the Lense-Thirring effect by a factor of 10. The Lense-Thirring effect is the part of Albert Einstein’s theory of general relativity that describes the distortion of space-time caused by the rotation of a body with mass. After LARES is deployed during Vega’s inaugural flight, the launcher’s AVUM fourth stage will then perform a maneuver lowering its perigee to 350 km. before deploying the eight other satellites. The largest of these is ALMASat-1 (the ALma MAter SATellite), a 12.5-kilogram technology demonstrator microsatellite developed and built by the University of Bologne. Its launch will test the performance of this low-cost, multipurpose 30-centimeter platform to prepare for future missions in technology demonstration applications or Earth observation. Completing the satellite payload are seven CubeSats that have been developed by more than 250 university students from six different countries. They represent four years of work in the European Space Agency’s CubeSat program, which began in 2007 when the organization decided to include an educational payload on the Vega launch vehicle’s maiden flight. The CubeSats are picosatellites of standardized dimensions – cubes of 10-centimeter per side, with a maximum mass of a kilogram – which can be operated from university or radio amateur ground stations. They serve as an educational tool that offers hands-on experience for aerospace engineering students in designing, developing, testing and operating a spacecraft system and its ground segment. Arianespace’s light-lift Vega rocket completed an intricate second launch from ELA-1 site in Kourou on May 6, 2013, at 11:06:31 p.m. successfully delivering three satellite passengers at two different Sun-synchronous orbital altitudes during a flight lasting just over two hours. Under a steady rain, Vega’s P80 solid propellant first stage is ignited to lift the Proba-V, VNREDSat-1 and ESTCube-1 satellite payloads. For this launch, Arianespace assumed Vega operations responsibility for the first time. The launch also marked the initial use of a multi-payload dispenser called VESPA (Vega Secondary Payload Adapter), which carried the Proba-V satellite atop it, while the VNREDSat-1 and ESTCube-1 spacecraft were installed inside the system. Additionally, VREDSat-1 became the initial commercial satellite lofted by Vega. The mission was also the debut of the Europe Space Agency’s VERTA (Vega Research and Technology Accompaniment) flight series to demonstrate the launcher’s flexibility and versatility. After the initial powered phase performed by Vega’s three solid propellant stages (designated the P80, Zefiro-23 and Zefiro-9), the launcher’s AVUM upper stage was ignited for four separate burns during the payload deployment sequence. A final burn was planned to deorbit the upper stage – ensuring it does not remain as a debris threat. The Proba-V satellite was released first during the flight profile, with this passenger to operate in a Sun-synchronous orbit of 820 km. Proba-V (which is named from the acronym: Project for On-Board Autonomy and Vegetation) is part of the European Space Agency’s Proba spacecraft series that supports the development of new space technologies. Its primary objective is to continue the mission performed by Earth-monitoring Vegetation instruments carried on the Spot 4 and 5 satellites – which also were launched by Arianespace – and is designed to offer global coverage every two days for data on the influence of climate, the management of resources for surface water, monitoring of changes in agricultural zones, and food security estimates. Proba-V was built by QinetiQ Space Belgium, and weighed approximately 140 kg. at launch. The VNREDSat-1 optical satellite was separated second, providing a resource for Vietnam’s initiative to create an infrastructure enabling better studies of climate change effects, improving predictions for natural disasters and optimizing natural resource management for the country. This 115-kilogram-class spacecraft was built by Astrium on behalf of the Vietnam Academy of Science and Technology, VAST. Completing the mission was Vega’s deployment of ESTCube-1, Estonia’s first satellite. The 1.33-kilogram cubesat was to extend a small conductive tether for testing of electric solar wind sail technologies, and also was to help establish an Estonian infrastructure for future space projects. It resulted from a collaboration of students from Tartu University, Estonian Aviation Academy, Tallinn University of Technology and University of Life Sciences, and was developed in conjunction with the Finnish Meteorological Institute and the German Space Center (DLR). Both VNREDSat-1 and ESTCube-1 were released for their operational lifetimes in Sun-synchronous orbits, bringing Vega’s 2-hour flight to a successful conclusion on May 7. Vega project chronology: 1988: Difesa Spazio proposes a vehicle to the Italian Space Agency, ASI, to replace the retired US Scout launcher by a new one based on the Zefiro motor developed from the company’s Ariane expertise. 1998 April: ESA’a Council approves a resolution authorizing pre-development activity. 2000 November 27-28: ESA's Ariane Programme Board approves the Vega project. 2000 Dec. 15: Seven countries members of ESA subscribe to a declaration authorizing the development of the Vega launcher. 2002 December: GKB Yuzhnoe wins an international tender for the development of the fourth stage engine for the Vega launcher. 2005 December: The Zefiro 9 third-stage solid-propellant engine fires for the first time during a static test. 2011 Sept. 26: The stages (A2, A3, A4) transported from AVIO facility in Colleferro, Rome, to Livorno harbor to be loaded on a dedicated Arianespace ship for a trip to Kourou launch site. 2011 Oct. 25: The First Vega launcher arrives at Kourou launch site. 2012 Jan. 26: The assembly of the first Vega launcher for the VV01 mission is completed in Kourou. 2023 June 28: A test firing of the Zefiro-40 solid-propellant motor for the second stage of the Vega-C launch vehicle fails, endangering the planned return to flight of the rocket then expected at the end of the year.
Complete list of Vega launches:
Technical specifications of the Vega launcher (547):
Payload delivery capabilities of the Vega rocket into circular orbits from Kourou depending on the orbital inclination toward the Equator (547):
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