The Indian Space Research Organisation (ISRO) will thoroughly evaluate the indigenously built cryogenic engine for GSLV-D3 before finalising a launch date.

A cryogenic engine uses liquid hydrogen as fuel and liquid oxygen as an oxidiser in the upper stage of a rocket like the GSLV to deploy satellites in orbit.

If the fuel mix is not in the exact proportions, the rocket could explode in geo-synchronous orbit.

The GSLV-D3 will carry GSAT-4 communication satellite into the geo-stationary orbit about 36,000km above the earth.

To date, ISRO has used Russian-made cryo-engines for the GSLVs.