|Function||Medium-lift launch vehicle|
|Manufacturer||Indian Space Research Organisation|
|Country of origin||India|
|Cost per launch||₹367 crore (US$46 million)|
|Height||43.43 m (142.5 ft)|
|Diameter||4 m (13 ft)|
|Mass||640,000 kg (1,410,000 lb)|
|Payload to LEO|
|Mass||10,000 kg (22,000 lb)|
|Payload to GTO|
|Mass||4,000 kg (8,800 lb)|
|Family||Geosynchronous Satellite Launch Vehicle|
|Launch sites||Satish Dhawan Space Centre SLP, Andhra Pradesh, India|
|Total launches||4 (+1 suborbital)|
|Success(es)||4 (+1 suborbital)|
|Last flight||22 October 2022|
|People or cargo transported||CARE, Chandrayaan-2, OneWeb|
|First stage – S200 Boosters|
|Height||25 m (82 ft)|
|Diameter||3.2 m (10 ft)|
|Empty mass||31,000 kg (68,000 lb) each|
|Gross mass||236,000 kg (520,000 lb) each|
|Propellant mass||205,000 kg (452,000 lb) each|
|Powered by||Solid S200|
|Maximum thrust||5,150 kN (525 tf)|
|Specific impulse||274.5 seconds (2.692 km/s) (vacuum)|
|Burn time||128 s|
|Second stage – L110|
|Height||21.39 m (70.2 ft)|
|Diameter||4.0 m (13.1 ft)|
|Empty mass||9,000 kg (20,000 lb)|
|Gross mass||125,000 kg (276,000 lb)|
|Propellant mass||116,000 kg (256,000 lb)|
|Powered by||2 Vikas engines|
|Maximum thrust||1,598 kN (163.0 tf)|
|Specific impulse||293 seconds (2.87 km/s)|
|Burn time||203 s|
|Propellant||UDMH / N2O4|
|Third stage – C25|
|Height||13.545 m (44.44 ft)|
|Diameter||4.0 m (13.1 ft)|
|Empty mass||5,000 kg (11,000 lb)|
|Gross mass||33,000 kg (73,000 lb)|
|Propellant mass||28,000 kg (62,000 lb)|
|Powered by||1 CE-20|
|Maximum thrust||196.5 kN (20.04 tf)|
|Specific impulse||434 seconds (4.26 km/s)|
|Burn time||643 s|
|Propellant||LOX / LH2|
The Geosynchronous Satellite Launch Vehicle Mark III (GSLV Mk III), also referred to as the Launch Vehicle Mark 3 (LVM3), is a three-stage medium-lift launch vehicle developed by the Indian Space Research Organisation (ISRO). Primarily designed to launch communication satellites into geostationary orbit, it is also due to launch crewed missions under the Indian Human Spaceflight Programme.GSLV Mk III has a higher payload capacity than it’s predecessor, GSLV Mk II.
After several delays and a sub-orbital test flight on 18 December 2014, ISRO successfully conducted the first orbital test launch of GSLV Mk III on 5 June 2017 from the Satish Dhawan Space Centre.
In June 2018, the Union Cabinet approved ₹43.38 billion (US$540 million) to build 10 GSLV Mk III rockets over a five-year period.
The GSLV Mk III has launched CARE, India's space capsule recovery experiment module, Chandrayaan-2, India's second lunar mission, and will be used to carry Gaganyaan, the first crewed mission under Indian Human Spaceflight Programme. In October 2021, UK-based global communication satellite provider OneWeb entered into an agreement with ISRO to launch OneWeb satellites aboard the GSLV Mk III along with the PSLV, due to the launch services from Roscosmos being cut off, caused by the Russian Invasion of Ukraine.
ISRO initially planned two launcher families, the Polar Satellite Launch Vehicle for low Earth orbit and polar launches and the larger Geosynchronous Satellite Launch Vehicle for payloads to geostationary transfer orbit (GTO). The vehicle was reconceptualized as a more powerful launcher as the ISRO mandate changed. This increase in size allowed the launch of heavier communication and multipurpose satellites, human-rating to launch crewed missions, and future interplanetary exploration. Development of the GSLV Mk III began in the early 2000s, with the first launch planned for 2009–2010. The unsuccessful launch of GSLV D3, due to a failure in the cryogenic upper stage, delayed the GSLV Mk III development program. The GSLV Mk III, while sharing a name with the GSLV, features different systems and components.
The first static fire test of the S200 solid rocket booster, ST-01, was conducted on 24 January 2010. The booster fired for 130 seconds and had nominal performance throughout the burn. It generated a peak thrust of about 4,900 kN (1,100,000 lbf). A second static fire test, ST-02, was conducted on 4 September 2011. The booster fired for 140 seconds and again had nominal performance through the test. A third test, ST-03, was conducted on 14 June 2015 to validate the changes from the sub-orbital test flight data.
Human rated variant of S200 or HS200 was developed for the Gaganyaan programme. The first static fire test of HS200 was conducted on 13 May 2022 at SDSC SHAR for a duration of 135 seconds with no issues.
ISRO conducted the first static test of the L110 core stage at its Liquid Propulsion Systems Centre (LPSC) test facility at Mahendragiri, Tamil Nadu on 5 March 2010. The test was planned to last 200 seconds, but was terminated at 150 seconds after a leakage in a control system was detected. A second static fire test for the full duration was conducted on 8 September 2010.
The first static fire test of the C25 cryogenic stage was conducted on 25 January 2017 at the ISRO Propulsion Complex (IPRC) facility at Mahendragiri, Tamil Nadu. The stage fired for a duration of 50 seconds and performed nominally.
A second static fire test for the full in-flight duration of 640 seconds was completed on 17 February 2017. This test demonstrated consistency in engine performance along with its sub-systems, including the thrust chamber, gas generator, turbopumps and control components for the full duration.
After the suborbital test flight of GSLV Mk III, certain modifications were made to the vehicle to improve its performance. The propellant grain geometry of the head end segments were changed from a 10-lobed slotted configuration to a 13-lobed star configuration and propellant load was reduced to 205 tonnes (452,000 lb) to improve performance during transonic phase of flight. The payload fairing was modified to an ogive shape, and the S200 booster nosecones and inter-tank structure were redesigned to have better aerodynamic performance.
The first stage consists of two S200 solid motors, also known as Large Solid Boosters (LSB) attached to the core stage. Each booster is 3.2 metres (10 ft) wide, 25 metres (82 ft) long, and carries 207 tonnes (456,000 lb) of hydroxyl-terminated polybutadiene (HTPB) based propellant in three segments with casings made out of M250 maraging steel. It is the largest solid-fuel booster after the Space Shuttle SRBs and Ariane 5 SRBs. The flex nozzles can be vectored up to ±8° using electro-hydraulic actuators operating in blow-down mode and are used for vehicle control during the initial ascent phase. Hydraulic fluid for operating these actuators is stored in an externally mounted cylindrical tank at the base of each booster. These boosters burn for 130 seconds and produce an average thrust of 3,578.2 kilonewtons (804,400 lbf) and a peak thrust of 5,150 kilonewtons (1,160,000 lbf) each.
The second stage, designated L110, is a liquid-fueled stage that is 21 metres (69 ft) tall and 4 metres (13 ft) wide, and contains 110 metric tons (240,000 lb) of unsymmetrical dimethylhydrazine (UDMH) and nitrogen tetroxide (N2O4). It is powered by two Vikas 2 engines, each generating 766 kilonewtons (172,000 lbf) thrust, giving a total thrust of 1,532 kilonewtons (344,000 lbf). The L110 is the first Indian clustered liquid-fueled engine. The Vikas engines uses regenerative cooling, providing improved weight and specific impulse compared to earlier Indian rockets. Each Vikas engine can be individually gimbaled to control vehicle pitch, yaw and roll control. The L110 core stage ignites 114 seconds after liftoff and burns for 203 seconds. Since the L110 stage is air-lit, its engines need shielding during flight from the exhaust of the operating S200 boosters and reverse flow of gases by a 'nozzle closure system' which gets jettisoned prior to L110 ignition.
The cryogenic upper stage, designated C25, is 4 metres (13 ft) in diameter and 13.5 metres (44 ft) long, and contains 28 metric tons (62,000 lb) of propellant LOX and LH2, pressurized by helium stored in submerged bottles. It is powered by a single CE-20 engine, producing 200 kN (45,000 lbf) of thrust. CE-20 is the first cryogenic engine developed by India which uses a gas generator, as compared to the staged combustion engines used in GSLV.
The CFRP composite payload fairing has a diameter of 5 metres (16 ft) and a payload volume of 110 cubic metres (3,900 cu ft).
Main article: SCE-200
The L110 core stage in the GSLV Mk III is planned to be replaced by the SC120, a kerolox stage powered by the SCE-200 engine to increase its payload capacity to 7.5 metric tons (17,000 lb) to geostationary transfer orbit (GTO). The SCE-200 uses kerosene instead of unsymmetrical dimethylhydrazine (UDMH) as fuel and has a thrust of around 200 tonnes. Four such engines can be clustered in a rocket without strap on boosters to deliver up to 10 tonnes (22,000 lb) to GTO. The first propellant tank for the SC120 was delivered in October 2021 by HAL.
The SC120-powered version of GSLV will not be used for the crewed mission of the Gaganyaan spacecraft.
The C25 stage with nearly 25 t (55,000 lb) propellant load will be replaced by the C32, with a higher propellant load of 32 t (71,000 lb). Total mass of avionics will be brought down by using miniaturised components. On 30 November 2020, Hindustan Aeronautics Limited delivered an aluminium alloy based cryogenic tank to ISRO. The tank has a capacity of 5,755 kg (12,688 lb) of fuel, and a volume of 89 m3 (3,100 cu ft), increasing payload capacity of GSLV Mk III.
In September 2019, a report from Astrotalk quoted that S. Somanath, director of Vikram Sarabhai Space Centre confirmed that the SCE-200 engine was ready to begin testing. As per an agreement between India and Ukraine signed in 2005, Ukraine was expected to test components of the SCE-200 engine, so an upgraded version of the GSLV Mk III was not expected arrive before 2022.
The SCE-200 engine is reported to be based on the Ukrainian RD-810, which itself is proposed for use on the Mayak family of launch vehicles.
While the GSLV Mk III is being human rated for Gaganyaan project, the rocket was always designed with potential human spaceflight applications in consideration. The maximum acceleration during ascent phase of flight was limited to 4 Gs for crew comfort and a 5 meter diameter payload fairing was used to be able to accommodate large modules like space station segments.
Furthermore, a number of changes to make safety-critical subsystems reliable are planned for lower operating margins, redundancy, stringent qualification requirements, revaluation, and strengthening of components.
The maiden flight of the GSLV Mk III lifted off from the Second Launch Pad at the Satish Dhawan Space Center on 18 December 2014 at 04:00 UTC. The test had functional boosters, a core stage but carried dummy upper stage. It also carried the Crew Module Atmospheric Re-entry Experiment (CARE) that was tested on re-entry.
Just over five minutes into the flight, the rocket ejected CARE at an altitude of 126 kilometres (78 mi), which then descended, controlled by its onboard reaction control system. During the test, CARE's heat shield experienced a peak temperature of around 1,000 °C (1,830 °F). ISRO downlinked launch telemetry during the ballistic coasting phase until the radio black-out to avoid data loss in the event of a failure. At an altitude of around 15 kilometres (9.3 mi), the module's apex cover separated and the parachutes were deployed. CARE splashed down in the Bay of Bengal near the Andaman and Nicobar Islands and was recovered successfully.
The first orbital flight of the GSLV Mk III occurred on 5 June 2017, lifting off from the Second Launch Pad at 11:58 UTC. The vehicle carried the GSAT-19 communication satellite, making it the heaviest Indian rocket and payload ever launched. The satellite was successfully placed into a geostationary transfer orbit (GTO) at 170 kilometres (110 mi). The flight also tested upgrades to the design from data acquired during the suborbital test flight.
The first operational flight occurred on 22 July 2019, lifting off from the Second Launch pad at 9:13 UTC. The rocket carried Chandrayaan-2, India's second mission to the Moon, consisting of an orbiter, lander and a rover. The Chandrayaan-2 stack is the heaviest spacecraft launched by ISRO.
This was the first commercial launch of GSLV Mk III that occurred on 22 October 2022, which helped India to enter the global market for heavier payloads. This was also the first launch of GSLV Mk III to a polar low earth orbit, the first multi-satellite mission and also the heaviest payload launched by ISRO to date, carrying a payload of about 6 tons.
|Flight №||Date / time (UTC)||Rocket,
|Launch site||Payload||Payload mass||Orbit||User||Launch |
|X||18 December 2014
|LVM3||Second Launch Pad||Crew Module Atmospheric Re-entry Experiment (CARE)||3,775 kg (8,322 lb)||Sub-orbital||ISRO||Success|
|Sub-orbital development test flight with a non-functional cryogenic stage|
|D1||5 June 2017
|Mk III||Second Launch Pad||GSAT-19||3,136 kg (6,914 lb)||GTO||INSAT||Success|
|First orbital test launch with a functional cryogenic stage|
|D2||14 November 2018
|Mk III||Second Launch Pad||GSAT-29||3,423 kg (7,546 lb)||GTO||INSAT||Success|
|Second orbital test flight. L110 core used upgraded Vikas engines with higher thrust.|
|M1||22 July 2019
|Mk III||Second Launch Pad||Chandrayaan-2||3,850 kg (8,490 lb)||EPO||ISRO||Success|
|First operational flight of GSLV MK-III.|
|M2||22 October 2022
|LVM3||Second Launch Pad||OneWeb × 36||5,796 kg (12,778 lb)||LEO||OneWeb||Success|
|First commercial launch of GSLV Mk III (LVM3) for OneWeb. Launch of 36 OneWeb satellites to 605km circular polar orbit. It is the heaviest payload that is launched by a GSLV Mk III (LVM3) and ISRO to date.|
|Date / time (UTC)||Rocket,
|February 2023||LVM3||Second Launch Pad||OneWeb × 36 (~5400 kg)||LEO|
|Second commercial launch of GSLV Mk III (LVM3) for OneWeb, designated as Flight M3.|
|June 2023||LVM3||Second Launch Pad||Chandrayaan-3||TLI|
|Mission repeat of Chandrayaan-2 with a lunar lander and rover.|
|TBD||Mk III||Second Launch Pad||GSAT-20 (CMS-03)||GTO|
|Late 2023/2024||Mk III||Second Launch Pad||G1||LEO|
|First uncrewed orbital demonstration flight of India's crew module.|
|2024||Mk III||Second Launch Pad||G2||LEO|
|Second uncrewed orbital demonstration flight of crew module.|
|2024||Mk III||Second Launch Pad||H1||LEO|
|India's first crewed mission. Launch mass is 7,800 kg (17,200 lb) with service module, capsule's mass is 3,735 kg.|
|December 2024||Mk III||Second Launch Pad||Shukrayaan-1||TBD|
|Launch mass is 2,500 kg; Venus orbiter and atmospheric balloon.|
|2024||Mk III||Second Launch Pad||Mangalyaan 2||TBD|
|India's second orbiter mission to Mars.|
|TBA||Mk III||Second Launch Pad||GSAT-22||GTO|
Isro had gone through a difficult period a few years ago, when a launch of its GSLV Mark II failed. This failure had its impact on GSLV Mark III as well. “Because we had problems with Mark II,” says Isro chairman Kiran Kumar, “we had to rework some facilities of Mark III for Mark II. So Mark III got slightly delayed.”
The failure of GSLV-D3 in 2010, where the first indigenous Cryogenic Upper Stage (CUS) was flight-tested, impacted the C25 stage programme due to the priority assigned for the additional investigation tests and added qualification tests demanded on CUS engine systems.
Taking into account the LEO payload capability of up to 10 tonnes feasible with this vehicle, the payload fairing diameter was fixed as 5 metres to accommodate large modules like a space station segment or manned capsule. Incidentally, considering the possibility of future human space flight missions by India, the boost phase acceleration was capped at 4g, the standard human tolerance level accepted by spacefaring agencies.
In addition, ATF also successfully completed the acoustic qualification of the Strap on Electro Mechanical Actuator Structure for the GSLV MKIII launcher. This would help in improving reliability and also provide advantages in payload capability in comparison with the Electro Hydraulic actuators used earlier.
We will be checking the crew capsule for all parameters.