Geosynchronous Satellite Launch Vehicle

The Geosynchronous Satellite Launch Vehicle (GSLV) was envisioned and developed by the Indian Space Research Organisation in the 1990s to establish India's strategic self-reliance in launching heavy communication and meteorological satellites to high orbits.

Despite significant challenges in mastering cryogenic technology, the recent flights since 2017 have now demonstrated the vehicle's reliability, maturity, and strategic implications for the country across domains. The GSLV stands today as a fitting symbol of indigenous technological capabilities.

About GSLV

GSLV is a fourth-generation launch vehicle designed to place communication satellites in geostationary transfer orbit using a cryogenic third stage. Cryogenic engines consist of liquid hydrogen and liquid oxygen — which provide far greater thrust than the engines used in the older launch vehicles. It was used for launching Chandrayaan-2.

History of GSLV

• The PSLV, operational since 1993, did not have sufficient payload capacity to place satellites in geosynchronous transfer orbit.
• Realizing the strategic imperative for sovereign satellite launch capability, the ISRO initiated the GSLV development in 1990 to achieve self-reliance in launching heavy INSAT satellites essential for communication, meteorology, and other crucial national services.
• In 2000, the first experimental flight of GSLV carried GSAT-1 satellite but failed to deliver it to designated orbit due to the limitation of cryogenic stage performance.
• The first successful GSLV flight with an indigenous cryogenic upper stage only occurred in January 2014 when GSLV-D5 launched the GSAT-14 satellite.
• Since 2017, GSLV has achieved 6 straight successful developmental & operational flights, establishing reliability.

GSLV Description 

The technical specifications of GSLV include:

Variants of GSLV

• GSLV Mk I
  • The first generation GSLV with a payload capacity of carrying 2-2.5 ton satellites to Geosynchronous Transfer Orbit.
  • It used the Russian-supplied cryogenic upper stage as it had early difficulty with mastering indigenous cryogenic technology.
  • It conducted around 5 flights from 2001-2010, including suborbital tests, with the last launch in 2010.
• GSLV Mk II
  • It is an enhanced variant with an indigenously developed cryogenic upper-stage engine and stage. It is capable of carrying payloads to GTO around the 2.5-ton class.
  • The first successful launch occurred in 2014. By 2022, it had undertaken 4 flights but is yet to demonstrate a high flight rate with yearly launches
• GSLV Mk III
  • The GSLV Mk III, also known as LVM-3, is the most advanced and powerful variant in the GSLV series, currently in service with a payload capacity of up to 4 tons to Geosynchronous Transfer Orbit (GTO).

Performance of GSLV

• The GSLV has launched various satellites, including communication satellites like INSAT and GSAT, as well as spacecraft from the NavIC and IDRSS series, into Geosynchronous Transfer Orbit (GTO)
• Notable missions include the launch of the South Asia Satellite in 2017, a satellite for military applications in 2018, and the Chandrayaan-2 moon mission in 2019. 

Significance of GSLV

For India's civilian space program and related national interests in the economic, technological, and security domains, the successful development of GSLV is of great strategic importance:

• Strategic Autonomy: The GSLV program provides a reliable indigenous launch capability, ends dependency on foreign commercial launchers, ensures self-reliance, and fortifies India's space assets and infrastructure while securing the space program.
• Economic Benefits: It saves costs through launch self-reliance, enables space-based services for socio-economic growth, and facilitates commercial launches to generate revenue.
• Technology Demonstration: The GSLV stands as a symbol of India's mastery of complex cryogenic rocket technology, showcasing the country's indigenous scientific and technical prowess.
• Enabler of Progress: It enables rapid launches tailored to India's needs, expands the country's space program ambitions and capacities, and facilitates the exploration of new strategic domains such as human spaceflight.
• Strengthening Security: The GSLV enables India to launch dedicated military and intelligence satellites, enhancing surveillance, communication, early warning, and deterrence capabilities for national security through independent access to space.

GSLV UPSC PYQs

Question 1: With reference to India's satellite launch vehicles, consider the following statements:

1. PSLVs launch satellites useful for Earth resources monitoring whereas GSLVs are designed mainly to launch communication satellites.
2. Satellites launched by PSLV appear to remain permanently fixed in the same position in the sky, as viewed from a particular location on Earth.
3. GSLV Mk III is a four-stage launch vehicle with the first and third stages using solid rocket motors, and the second and fourth stages using liquid rocket engines.

Which of the statements given above is/are correct? (UPSC Prelims 2018)

1. 1 only
2. 2 and 3
3. 1 and 2
4. 3 only

Answer: (a)

GSLV FAQs

Q1. What is the full form of GSLV?

Ans. The full form of GSLV is the Geosynchronous Satellite Launch Vehicle, a satellite launch vehicle developed and operated by the ISRO.

Q2. What is PSLV and GSLV?

Ans. Both PSLV and the GSLV are satellite launch vehicles developed by ISRO. The PSLV is for polar and GTO orbits, while the GSLV is for communication satellites to GTO.

Q3. Why is GSLV called the naughty boy of ISRO?

Ans. The GSLV has been nicknamed the "naughty boy" due to its inconsistent performance history, with some successful launches and others failing. However, the GSLV-F14 mission, which launched the INSAT-3DS meteorological satellite, marked a significant turnaround for the GSLV program, shedding its notorious tag.