Launch vehicle fleet

During the 1960s and 1970s, India initiated its own launch vehicle program owing to geopolitical and economic considerations. In the 1960s–1970s, the country successfully developed a sounding rockets programme, and by the 1980s, research had yielded the Satellite Launch Vehicle-3 and the more advanced Augmented Satellite Launch Vehicle (ASLV), complete with operational supporting infrastructure.^[32] ISRO further applied its energies to the advancement of launch vehicle technology resulting in the creation of PSLV and GSLV technologies.

Satellite Launch Vehicle (SLV)

Status: Decommissioned

The Satellite Launch Vehicle, usually known by its abbreviation SLV or SLV-3 was a 4-stage solid-propellant light launcher. It was intended to reach a height of 500 km and carry a payload of 40 kg.^[33] Its first launch took place in 1979 with 2 more in each subsequent year, and the final launch in 1983. Only two of its four test flights were successful.^[34]

Augmented Satellite Launch Vehicle (ASLV)

Status: active

The Augmented Satellite Launch Vehicle, usually known by its abbreviation ASLV was a 5-stage solid propellant rocket with the capability of placing a 150 kg satellite into Low Earth Orbit. This project was started by the ISRO during the early 1980s to develop technologies needed for a payload to be placed into a geostationary orbit. Its design was based on Satellite Launch Vehicle.^[35] The first launch test was held in 1987, and after that 3 others followed in 1988, 1992 and 1994, out of which only 2 were successful, before it was decommissioned.^[34]

Polar Satellite Launch Vehicle (PSLV)

Status: Active

The Polar Satellite Launch Vehicle, commonly known by its abbreviation PSLV, is an expendable launch system developed by ISRO to allow India to launch its Indian Remote Sensing (IRS) satellites into Sun synchronous orbits. PSLV can also launch small satellites into geostationary transfer orbit (GTO). The reliability and versatility of the PSLV is proven by the fact that it has launched, as of 2014, 71 satellites/spacecraft (31 Indian and 40 foreign) into a variety of orbits.^[36][37] The maximum number of satellites launched by the PSLV in a single launch is 104, in the PSLV-C37 launch on 15 February 2017.^[38][39][40]

Decade-wise summary of PSLV launches:

Decade	Successful	Partial success	Failures	Total
1990s	3	1	1	5
2000s	11	0	0	11
2010s	24	0	1	25

Geosynchronous Satellite Launch Vehicle (GSLV)

Status: Active

The Geosynchronous Satellite Launch Vehicle, usually known by its abbreviation GSLV, is an expendable launch system developed to enable India to launch its INSAT-type satellites into geostationary orbit and to make India less dependent on foreign rockets. At present, it is ISRO's second-heaviest satellite launch vehicle and is capable of putting a total payload of up to 5 tons to Low Earth Orbit. The vehicle is built by India, originally with a cryogenic engine purchased from Russia, while the ISRO developed its own cryogenic engine.

The first version of the GSLV (GSLV Mk.I), using the Russian cryogenic stage, became operational in 2004, after an unsuccessful first launch in 2001 and a second, successful development launch in 2003.

The first attempt to launch the GSLV Mk.II with an Indian built cryogenic engine, GSLV-F06 carrying GSAT-5P, failed on 25 December 2010. The initial evaluation implies that loss of control for the strap-on boosters caused the rocket to veer from its intended flight path, forcing a programmed detonation. Sixty-four seconds into the first stage of flight, the rocket began to break up due to the acute angle of attack. The body housing the 3rd stage, the cryogenic stage, incurred structural damage, forcing the range safety team to initiate a programmed detonation of the rocket.^[41]

On 5 January 2014, GSLV-D5 successfully launched GSAT-14 into intended orbit. This marked first successful flight using indigenous cryogenic engine (CE-7.5), making India the sixth country in the world to have this technology.^[5][6]

Again on 27 August 2015, GSLV-D6 launched GSAT-6 into the transfer orbit. ISRO used the indigenously developed Cryogenic Upper Stage (CUS) third time on board in this GSLV flight.^[42]

On 8 September 2016, GSLV-F05 successfully launched INSAT-3DR, an advanced weather satellite, weighing 2211 kg into a Geostationary Transfer Orbit (GTO). GSLV is designed to inject 2 – 2.5 Tonne class of satellites into GTO. The launch took place from the Second Launch Pad at Satish Dhawan Space Centre SHAR (SDSC SHAR), Sriharikota. GSLV-F05 flight is significant since it is the first operational flight of GSLV carrying Cryogenic Upper Stage (CUS). The indigenously developed CUS was carried on board for the fourth time during a GSLV flight in the GSLV-F05 flight. GSLV-F05 vehicle is configured with all its three stages including the CUS similar to the ones successfully flown during the previous GSLV-D5 and D6 missions in January 2014 and August 2015.^[43]

Decade-wise summary of GSLV Launches:

Decade	Successful	Partial success	Failures	Total
2000s	3	1	1	5
2010s	5	0	2	7

Geosynchronous Satellite Launch Vehicle Mark-III (GSLV III)

Status: Active

GSLV-Mk III is a launch vehicle. It is capable to launch four tonne satellites into geosynchronous transfer orbit. GSLV-Mk III is a three-stage vehicle with a 110 tonne core liquid propellant stage (L-110) flanked by two 200 tonne solid propellant strap-on booster motors (S-200). The upper stage is cryogenic with a propellant loading of 25 tonne (C-25). The vehicle has a lift-off mass of about 640 tonnes and be 43.43 metres tall. According to ISRO, the payload fairing has a diameter of 5 metres and a payload volume of 100 cubic metres.^[44] It will allow India to become less dependent on foreign rockets for heavy lifting.^[45]

On 18 December 2014, ISRO successfully conducted an experimental test-flight of GSLV MK III carrying a crew module, to be used in future human space missions.^[46] This suborbital test flight demonstrated the performance of GSLV Mk III in the atmosphere.^[47]

GSLV Mk III-D1 carrying communication satellite GSAT-19 lifted off from the second launch pad at Satish Dhawan Space Centre in Sriharikota on 5 June 2017 and placed the advanced communication satellite into the geosynchronous transfer orbit 16 minutes after takeoff. GSAT-19 satellite with a lift-off mass of 3136 kg, is the communication satellite of India, configured around the ISRO’s standard I-3K bus.^[48]

Decade wise summary of GSLV III launches:

Decade	Successful	Partial success	Failures	Total
2010s	2	0	0	2[