It is not necessary to convince anybody in space industry about potential in ISRO and Indian space industry. If anyone could have any doubts now it should disappear. ISRO finished ground tests of their new cryogenic engine for third stage for GSLV launch vehicle.
ISRO is still developing own launch vehicles to remain competitive not only because of the price per kg of the launched payload. There is a chance that GSLV Mark 3 will became new quality in launch services offered by ISRO and will help India to get to the first league of national launch service providers in Asia region. In spite of often utilized and reliable PSLV (Polar Satellite Launch Vehicle), ISRO decided in 1990 to develop larger rocket with better parameters; until developing GSLV all INSAT satellites could not be launched in India. GSLV was strongly based on construction of PSLV with four boosters and first two stages. Third stage was result of cooperation with Russian company Glavcosmos – Russian companies were not worrying about sanctions which were put on India by USA after violating Missile Technology Control Regime. First GSLV Mark 1 was launched in on 18 April 2001 but due the problems it was not able to reach geosynchronous orbit and perform correct injection of GSAT-1 satellite. Next flights of GSLV Mark 1 were performed in 2003 (success with GSAT-2), 2004 (success with EDUSAT satellite), 2006 (failure with IN×–T-4C satellite), 2007 (partial success – INSAT-4CR reached final orbit with own propulsion). First GSLV Mark 2 flights were failure – in April and December 2010 due the problems with Russian engines and flight control issues. First success of Mark 2 happened in 2014 when rocket started to be equipped in Indian CE-7.5 which replaced Russian RD-56. Next step of ISRO was further development to improve payload capacity of GSLV. As main objective during modifying GSLV Mark 2 was change of propulsion – CE-7.5 engine was generating not enough thrust to lift more payload to GTO orbit. ISRO started development of LVM3 engine which was assumed to double payload capacity of Mark 3 variant. LVM3 is liquid fueled cryogenic engine. It means that for better performance fueled will be pumped into engine with lower temperature as in regular engines. In LVM3 hydrogen has temperature at -253° C and oxygen at -193° C.
GSLV (specification refers to Mark 2) is three stage rocket with length of 49 m, weight of 457 t and 7.8 m long payload fairing (with 3.4 m diameter). It is able to lift up to 2500 kg to GTO orbit. Four boosters are liquid fueled and powered by one L40H Vikas 2 engine with thrust at 3040 kN It is three stage rocket solid and liquid fueled. First stage is solid fueled with HTPB and powered by S139 engine providing 4700 kN of thrust. Second stage is liquid fueled with N2O4/UDMH – one GS2 Vikas engine is providing 800 kN of thrust. Third stage is cryogenic and powered by CE-7.5 engine with thrust 75 kN and powered by LOX/LH2.