A crucial ground test of the indigenously-developed cryogenic engine that will replace the Russian-supplied upper stage of India's three-stage Geosynchronous Satellite Launch Vehicle (GSLV) was carried out successfully on 15 November.

The final test represents a significant development in the Indian space programme.

The stage is powered by a regeneratively cooled cryogenic engine, which works on stage combustion cycle, developing a thrust of 15,620lb (69.5kN) in vacuum.

Describing the 720s test as "completely successful", Indian Space Research Organisation chairman G Madhavan Nair said: "It was a fantastic achievement that has boosted the confidence of ISRO."

With the indigenous cryogenic engine, the launch capability of GSLV, which is now around 2t, would be boosted to 2.5t "after some fine tuning", he says.

ISRO took up the cryogenic upper-stage project in the 1990s after Russia, under pressure because of US concerns about proliferation of missile technology, dropped plans to transfer the technology to ISRO.

Russia did supply a few cryogenic engine stages for the GSLV, the first two stages of which are derived from the modules of the Indian space workhorse, the four-stage Polar Satellite Launch Vehicle.

Source: FlightGlobal.com