The European Space Agency announced Tuesday that it will go ahead with development of a small rocket with technology steming from the venerable Ariane rockets.

The decision was made when ESA member countries voted to proceed with the full development of the Vega rocket and an associated solid-fueled propulsion system that could one day increase payload performance on the Ariane 5 rocket. ESA officials say that the first launch of the new small launch vehicle is targeted for late 2005.

An artist's concept of Vega rocket launches from Kourou, French Guiana. Photo: ESA

Under consideration since 1998, the Vega launch system consists of three solid-fueled stages and a liquid-fueled attitude control system. Most of the technology has been proven in flight using the Ariane 4 and Ariane 5 rockets.

The first stage features a solid rocket motor based upon an Ariane 5 solid-fueled booster, with only a few changes taking place, such as a new gimballing nozzle. The first stage has yet to be tested with all new additions in place.

Stage two of the rocket has been in development since the idea of the Vega launch system was first brought up in 1998. The Italian Space Agency funded the initial development of the so-called Zefiro motor. The 16-ton stage has a length of almost 15 feet and a diameter of almost 6 feet.

Three static test firings of the Zefiro motor have been conducted to date by Fiat Avio, the most recent having occurred on December 15. If no problems crop up, two more firings of the Zefiro are planned to fully qualify the motor for use on Vega.

Vega's third stage presented the design team with a several challenges before a final configuration was decided upon. Details on the third stage are still sketchy, but the stage will weigh around 7 tons and will sport the same diameter as the Zefiro second stage. Drawings of the rocket show that the third stage will be a little less than one-half the size of the Zefiro stage.

The Attitude and Vernier Upper Module (AVUM) will use conventional steering jets and storable propellants to provide attitude control and minor orbital parameter changes during the final few minutes of a launch. The AVUM will be positioned directly above the third stage of the Vega rocket and below the payload section of the launch vehicle.

Current plans call for the Vega launcher to be boosted skyward from the Guiana Space Center in Kourou, French Guiana. This is the same site that rockets from the Ariane family are launched. It was chosen for Vega because it provides unique opportunities to launch into polar and equatorial orbits, thus enlarging Vega's potential market. As of 1998, when the initial plans were published, the Vega rocket was to launch from either ELA-1, which used by older versions of the Ariane rocket and has since been retired, or ELA-3, which is used currently by the Ariane 5. However, ESA says that the ELA-1 site is preferred because of interference issues with Ariane 5 operations.

Vega's launch market aims at the smaller satellite market. Currently, the Vega is planned to have a mass-to-orbit of around 3,300 pounds to an orbit around 500 miles high, or a mass-to-orbit of around 1,500 pounds to an orbit just under 1,000 miles high. Such light to medium-class spacecraft are becoming more and more popular in the fields of science, technology demonstration and telecommunications.

The Vega rocket is the only small launch vehicle currently in serious development in Europe and will compete with rockets that are already in place or in development in Russia and the United States.

ESA, the French space agency CNES, and the Italian Space Agency (ASI), all of which help oversee the development and testing of the Vega launch system, are targeting to keep the launch price of Vega at least 15 percent below those in the United States. A target price of $20 million has been set by the marketing team for an approximate 2,200 pound payload.

Plans call for three to four launches to be conducted in the first few years of launch operations, steadily increasing to around six launches per year when the final phase of operations begin. Once in the final marketing stage, Arianespace will oversee the daily business of the Vega rocket.

Fiat Avio and Aerospatiale are the two principal contractors for the launch vehicle.