r bulletin 109 — february 2002 Vega: The European Small-Launcher Programme R. Barbera & S. Bianchi Vega Department, ESA Directorate of Launchers, ESRIN, Frascati, Italy Background The programme was adopted by ESA in June The origins of the Vega Programme go back to 1998, but the funding was limited to a Step 1, the early 1990s, when studies were performed with the aim of getting the full approval by the in several European countries to investigate the European Ministers meeting in Brussels in May possibility of complementing, in the lower 1999. This milestone was not met, however, payload class, the performance range offered because it was not possible to obtain a wide by the Ariane family of launchers. The Italian consensus from ESA’s Member States for Space Agency (ASI) and Italian industry, in participation in the programme. This gave rise to particular, were very active in developing a period of political uncertainty and to a series concepts and starting pre-development work of negotiations aimed at finding an agreeable based on established knowhow in solid compromise. It is important, on the other hand, propulsion. When the various configuration to record that during the same period the options began to converge and the technical technical definition work continued without feasibility was confirmed, the investigations major disruption, and development tests on the were extended to include a more detailed Zefiro motor were successfully conducted. definition in terms of a market analysis and related cost targets. The subsequent extension of the duration of Step 1 provided the opportunity to revisit and By the end of 2001, the development programme for Europe’s new update the market analysis, based on the small Vega launcher was well underway. The System Preliminary evolution taking place in terms of potential Design Review had been concluded in July 2001 with positive results, customers and competitors. The result of this confirming that the technical baseline is sound and consistent with exercise indicated the need to refocus the the strict system and programmatic requirements. At motor- reference mission towards Earth-observation development level, the Zefiro motor that will power Vega’s second payloads, and to increase Vega’s performance stage has already undergone one demonstration and two to be able to launch a 1500 kg satellite into a development full-scale firing tests at the Sardinia test range. The next 700 km polar orbit, whilst still maintaining the key milestones are the System Design Review (SDR) foreseen for early cost target. Several iterations were performed 2003 and the Critical Design Review (CDR) scheduled for March 2004. to optimise the configuration, the results of The parallel activities for Vega’s new first-stage P80 motor and for the which are summarised later in this article. ground segment are also progressing according to plan, and are consistent with a first Vega qualification flight by the end of 2005. One of the major options selected after technical and programmatic trade-offs is represented by the adoption, as the first stage As a conclusion of these preparatory activities, for Vega, of a new high-performance solid motor in February 1998 ASI proposed that a small featuring several technology advances, in launcher – in the meantime called ‘Vega’ – be particular a filament-wound (FW) case structure developed within the ESA framework as a co- not yet available in Europe for the size, propellant operative project with other ESA Member mass and internal pressure combination States. The main requirements as then defined needed. This new motor, called P80 FW in were: association with the 80 tonnes of propellant – launch of an 800 kg payload into Sun- mass, will not only offer increased performance synchronous orbit (SSO) at 1200 km altitude and lower production costs, but also pave the – launch from Kourou, French Guiana way to future applications for medium-size –a 2 m payload-envelope diameter launchers complementary to Ariane-5 and for a –maximum synergy with other Ariane develop- new generation of boosters for Ariane-5 itself. ments – low recurring cost (less than US$ 20 million) After about two years of definition and –a first launch before early 2003. consolidation activities, the Vega configuration, 64 vega including the new P80 FW first stage, two two main components: Earth Explorer, science- additional solid stages (Zefiro 23 and Zefiro 9) driven missions, and Earth Watch for as, respectively, second and third stages, and application missions. Both are based on the upper module AVUM, was established and multiple small missions instead of another ready for development as an ESA programme. single large satellite like Envisat. Small satellites On the other hand, the choice of the P80 FW are increasingly being considered a suitable implied a stretching of the duration of the alternative to traditional satellites for visible- and programme to allow for the demonstration of radar-imaging military Earth-observation missions the new technologies involved. Consequently, also. the first launch of Vega is now scheduled by the end of 2005. The formal funding was granted For its scientific missions too, ESA is proposing by the participating European States in a family of small satellites to demonstrate December 2000, within a financial envelope of enabling technologies to be used for future 335 million Euros. Seven countries have larger missions (SMART for electric propulsion, subscribed to the programme: Italy, France, etc.). Spain, Belgium, the Netherlands, Switzerland and Sweden. In parallel, the development of In the field of telecommunications, two possible the P80 FW motor was approved, with a types of mission are identified for small budget of 123 million Euros, about half of which launchers. ‘Little LEO’ constellations, which are is provided by Fiat-Avio as an industrial dedicated to data transmission, store and contribution. In addition to Italy, France, forward services in real time and messaging Belgium and the Netherlands are participating applications, are based on satellites weighing in the funding of the P80 development. some hundreds of kilogrammes. These satellites may be launched as a single or Market opportunities for the Vega launcher multiple payload by a small launcher. ‘Big LEO’ The decision to develop a small launcher is a constellations are based on satellites of about response to a Resolution in the Space one ton. For these systems, spares management Transportation Strategy adopted by the ESA is not a trivial process, and the timely Council in June 2000, aiming at: “completing, replacement of a failed spacecraft typically in in the medium term, the range of launch less than two months allows a major saving. services offered by the addition of European- With constellations relying on a very large manufactured small and medium launcher, number of satellites, the market potential for complementary to Ariane, consistent with small launchers is linked to the need for such diversified users’ needs and relying on common replacements, it being understood that the elements, such as stages, subsystems, techno- overall deployment strategy will rely mainly on logies, production facilities and operational medium and heavy launchers. infrastructure, thereby increasing the European launcher industry’s competitiveness”. As a result of several different, independent assessments of the potential market for a Vega will also satisfy a potential market for European small launcher, it has been estimated launching small satellites identified in several that the number of European (and a few non- forecasts. NASA, for example, is putting an European) governmental missions that will emphasis on ‘small missions’ making use of make use of a small launcher will initially be of low-mass satellites and low-capacity launch the order of two per year, and may grow to four vehicles, and several European space agencies, per year after 2005, with a total of 30 to 35 especially the French and Italian agencies, will launches in the period 2004 – 2013. follow similar paths. The development of small- satellite standard platforms, such as Minisat, Current projections show that for little-LEO Proteus and PRIMA, has already been initiated. constellation deployment, and for big-LEO (e.g. It is expected that the availability of such Globalstar, Iridium) and broadband LEO standard platforms will attract several satellite replacement, the market is very applications, allowing cost reductions and new uncertain. Taking into account the rapid project starts. changes and the uncertainties as to how constellations will develop, the number of From a technical point of view, the recent additional payloads originating from the evolution in Earth-observation technologies is commercial applications is estimated to be one allowing a reduction in satellite masses. Optical or two per year. In the long term, an increased and infrared detectors are now much smaller launch rate may be envisaged as a consequence and, even in the field of radar observation, all- of two possible events: weather surveillance can be performed using satellites with masses of around 1 ton. ESA’s – confirmation of the validity of the small-mission Earth-Observation Programme currently has approach 65 r bulletin 109 — february 2002 –improvements in miniaturisation technologies by a cylindrical volume of 2.35 m diameter and for small satellites. 3.5 m height, plus an additional conical volume of 2.8 m (with a height of 2.8 m). Growth- In conclusion, combining the forecasts for the potential