Orbital Sciences and Aerojet have begun testing the AJ26 rocket engine for the Taurus II programme with the testing of the pathfinder engine.

The Aerojet-built AJ26 liquid-fuel rocket engine will be used on the first stage of Orbital’s Taurus II space launch vehicle, which is currently in development.

The pathfinder engine will verify test stand interfaces, engine handling processes and test configurations before a series of hot fire tests begin in April 2010.

Taurus II rockets will boost payloads into a range of low Earth and geosynchronous transfer orbits, and Earth escape trajectories.

The launch vehicle, powered by the ASJ26 engine, is expected to provide eight cargo missions to resupply the International Space Station (ISS) under a contract with Nasa.

The Taurus programme will undertake its first demonstration flight for the cargo missions in 2011.