An endurance test for duration of more than 16 minutes on the indigenous Cryogenic Engine for Geo-synchronous Satellite Launch Vehicle, GSLV, was successfully conducted December 5 at ISRO's Liquid Propulsion Systems Centre (LPSC) at Mahendragiri in Tamil Nadu. The test involved the firing of the Cryogenic main Engine with 7.1 tonne thrust for 1000 seconds, simultaneously with two 200 kg thrust Cryogenic Steering Engines, all mounted on a single block as used in the actual GSLV flight stage developing 7.5 tonne total thrust. The steering engines are used to control the flight path of GSLV during the third stage thrusting.

The turbo-pump fed, regeneratively cooled engine for the cryogenic stage is required to burn for a duration of 720 seconds in actual flight. The long duration test conducted Dec. 5 marks the conclusion of the qualification of the cryogenic engine, which has been tested for a cumulative duration of 6,000 seconds so far in three hardware. A number of specially established facilities like Assembly and Integration Facility, Test stand, state of the art Control Centre have been employed for the successful assembly and testing of engines.

The development of the cryogenic stage system is also progressing well at LPSC, Thiruvananthapuram. This cryogenic stage, using a combination of two tonne liquid hydrogen and 11 tonne liquid oxygen, is intended to replace the Russian supplied cryogenic stage in GSLV.

Dr G Madhavan Nair, Chairman, ISRO, Mr N Vedachalam, Director, LPSC, Dr B N Suresh, Director, Vikram Sarabhai Space Centre, Thiruvananthapuram, and other senior scientists of ISRO witnessed today's test.