Small advance for ESA

The European Space Agency last week successfully completed the first firing test of Zefiro 23, the second-stage motor of ESA’s Vega small satellite launch vehicle.

The static firing took place at the Italian ministry of defence test centre in Salto di Quirra, Sardinia. The 7.5m tall, 2m diameter motor, featuring a carbon epoxy filament-wound casing, delivered more than 100 tonnes of thrust (1,070kN), burning 24 tonnes of solid propellant in 75 seconds.

Data gathered during the test is being analysed to improve technical knowledge of the motor’s behaviour and refine the launcher’s future performance. Also tested during the firing were sub-systems, including a thrust vector control system that will steer the motor’s nozzle to provide flight control.

Built by Avio in Colleferro, near Rome, the Zefiro 23 motor will be the basis for the second stage of ESA’s Vega launcher. The first firing test with the third-stage motor — the Zefiro 9 — was performed in December 2005.

Conducted on behalf of ESA’s Vega development programme, these two firing tests followed three static firings of the Zefiro 16 demonstrator in 1998, 1999 and 2000. Zefiro 23 and Zefiro 9 will undergo an additional ground-firing test each to complete their development and qualification.

The first Vega flight is set for the end of 2007 from Europe’s Spaceport in French Guiana.

ESA’s Vega small-satellite launcher, under development since 1998, is an all-solid three-stage vehicle with a liquid-fuelled injection module.

Vega is designed to carry single or multiple payloads to orbits up to 1,500km in altitude.

Its baseline payload capability is about 1,500kg to a circular 700km high sun-synchronous orbit but it can also lift satellites from 300kg to more than two tonnes, as well as piggyback microsatellites.