Geosynchronous Satellite Launch Vehicle

Geosynchronous Satellite Launch Vehicle (GSLV) is an expendable launch system operated by the Indian Space Research Organisation (ISRO). GSLV was used in thirteen launches from 2001 to 2018, with more launches planned. Even though GSLV Mk III shares the name, it is an entirely different launcher.

Not to be confused with GSLV Mark III.
GSLV
FunctionMedium Lift Launch System
ManufacturerISRO
Country of originIndia
Cost per launchUS$47 million[1]
Size
Height49.13 m (161.2 ft)[2]
Diameter2.8 m (9 ft 2 in)
Mass414,750 kg (914,370 lb)
Stages3
Capacity
Payload to LEO5,000 kg (11,000 lb)[2]
Payload to GTO2,700 kg (6,000 lb)[2][3]
Launch history
Status
  • Mk.I: Retired
  • Mk.II: Active
Launch sitesSatish Dhawan
Total launches13 (6 Mk.I, 7 Mk.II)
Successes8 (2 Mk.I, 6 Mk.II)
Failures3 (2 Mk.I, 1 Mk.II)
Partial failures2 (Mk.I)
First flight
  • Mk.I: 18 April 2001
  • Mk.II: 15 April 2010
Last flight
  • Mk.I: 25 December 2010
  • Mk.II: 19 December 2018
Notable payloadsSouth Asia Satellite
Boosters
No. boosters4 L40 Hs
Length19.7 m (65 ft)[4]
Diameter2.1 m (6.9 ft)[4]
Propellant mass42,700 kg (94,100 lb) each [4]
Engines1 L40H Vikas 2
Thrust760 kN (170,000 lbf)[5]
Total thrust3,040 kN (680,000 lbf)
Specific impulse262 s (2.57 km/s)
Burn time154 seconds[4]
FuelN2O4/UDMH
First stage
Length20.2 m (66 ft)[4]
Diameter2.8 m (9.2 ft)[4]
Propellant mass138,200 kg (304,700 lb)[4]
Engines1 S139
Thrust4,846.9 kN (1,089,600 lbf)[5]
Specific impulse237 s (2.32 km/s)
Burn time100 seconds
FuelHTPB (solid)
Second stage
Length11.6 m (38 ft)[4]
Diameter2.8 m (9.2 ft)[4]
Propellant mass39,500 kg (87,100 lb)[4]
Engines1 GS2 Vikas 4
Thrust846.8 kN (190,400 lbf)[5]
Specific impulse295 s (2.89 km/s)
Burn time139 seconds[4]
FuelN2O4/UDMH
Second GS2 (GL40) stage
Length11.9 m (39 ft)[6]
Diameter2.8 m (9.2 ft)[6]
Propellant mass42,500 kg (93,700 lb)[6]
Engines1 GS2 Vikas 4
Thrust846.8 kN (190,400 lbf)[5]
Specific impulse295 s (2.89 km/s)
Burn time149 seconds[6]
FuelN2O4/UDMH
Third stage (GSLV Mk.II) – CUS12
Length8.7 m (29 ft)[4]
Diameter2.8 m (9.2 ft)[4]
Propellant mass12,800 kg (28,200 lb)[4]
Engines1 CE-7.5
Thrust75 kN (17,000 lbf)
Specific impulse454 s (4.45 km/s)
Burn time718 seconds[4]
FuelLOX/LH2
Third stage (GSLV Mk.II) – CUS15
Length9.9 m (32 ft)[6]
Diameter2.8 m (9.2 ft)[6]
Propellant mass15,000 kg (33,000 lb)[6]
Engines1 CE-7.5
Thrust75 kN (17,000 lbf)
Specific impulse454 s (4.45 km/s)
Burn time846 seconds[6]
FuelLOX/LH2

History

The Geosynchronous Satellite Launch Vehicle (GSLV) project was initiated in 1990 with the objective of acquiring an Indian launch capability for geosynchronous satellites.[7][8]

GSLV uses major components that are already proven in the Polar Satellite Launch Vehicle (PSLV) launchers in the form of the S125/S139 solid rocket booster and the liquid-fueled Vikas engine. Due to the thrust required for injecting the satellite in a GTO orbit the third stage was to be powered by a LOX/LH2 Cryogenic engine which at that time India did not possess or had the technology know-how to build one.

The first development flight of the GSLV (Mk.I configuration) was launched on 18 April 2001 was a failure as the payload failed to reach the intended orbit parameters. The launcher was declared operational after the second development flight successfully launched the GSAT-2 satellite. During the initial years from the initial launch to 2014 the launcher had a checkered history with only 2 successful launches out of 7.[9][10]

Cryogenic Engine Controversy

The third stage was to be procured from Russian company Glavcosmos, including transfer of technology and design details of the engine based on an agreement signed in 1991.[8] Russia backed out of the deal after US objected to the deal as in violation of the Missile Technology Control Regime (MTCR) May 1992. As a result, ISRO initiated the Cryogenic Upper Stage Project in April 1994 and began developing its own cryogenic engine.[11] A new agreement was signed with Russia for 7 KVD-1 cryogenic stages and 1 ground mock-up stage with no technology transfer, instead of 5 cryogenic stages along with the technology and design as per the earlier agreement.[12] These engines were used for the initial flights and were named GSLV Mk.1.[13]

Vehicle description
GSLV-F01 launched from the Satish Dhawan Space Centre, Sriharikota, to place EDUSAT -India's first communication satellite dedicated to educational purposes- in orbit on September 20, 2004

The 49 metres (161 ft) tall GSLV, with a lift-off mass of 415 metric tons (915,000 lb), is a three-stage vehicle with solid, liquid and cryogenic stages respectively. The payload fairing, which is 7.8 metres (26 ft) long and 3.4 metres (11 ft) in diameter, protects the vehicle electronics and the spacecraft during its ascent through the atmosphere. It is discarded when the vehicle reaches an altitude of about 115 km.[14]

GSLV employs S-band telemetry and C-band transponders for enabling vehicle performance monitoring, tracking, range safety / flight safety and preliminary orbit determination. The Redundant Strap Down Inertial Navigation System/Inertial Guidance System of GSLV housed in its equipment bay guides the vehicle from lift-off to spacecraft injection. The digital auto-pilot and closed loop guidance scheme ensure the required altitude maneuver and guide injection of the spacecraft to the specified orbit.

The GSLV can place approximately 5,000 kg (11,000 lb) into an easterly Low Earth orbit or 2,500 kg (5,500 lb)(for the Mk. II version) into an 18° geostationary transfer orbit.

Liquid boosters

The first GSLV flight, GSLV-D1 used the L40 stage. Subsequent flights of the GSLV used high pressure engines in the strap-on boosters called the L40H.[15] The GSLV uses four L40H liquid strap-on boosters derived from the L37.5 second stage, which are loaded with 42.6 tons of hypergolic propellants (UDMH & N2O4). The propellants are stored in tandem in two independent tanks 2.1 metres (6 ft 11 in) diameter. The engine is pump-fed and generates 760 kilonewtons (170,000 lbf) of thrust, with a burn time of 150 seconds.

First stage

GSLV-D1 used the S125 stage which contained 125 metric tons (276,000 lb) of solid propellant and had a burn time of 100 seconds. All subsequent launches have used enhanced propellant loaded S139 stage.[15] The S139 stage is 2.8 m in diameter and has a nominal burn time of 109 seconds.[16] The stage generates a maximum thrust of 4700 kN.[17]

Second stage

The GS2 stage is powered by the Vikas engine. It has a diameter of 2.8 metres (9 ft 2 in).[16]

Third stage

The third stage of the GSLV Mk.II is propelled by the Indian CE-7.5 cryogenic rocket engine while the older defunct Mk.I is propelled using a Russian made KVD-1. It uses liquid hydrogen (LH2) and liquid oxygen (LOX)[18] The Indian cryogenic engine was built at the Liquid Propulsion Systems Centre [19][20] The engine has a default thrust of 75 kilonewtons (17,000 lbf) but is capable of a maximum thrust of 93.1 kilonewtons (20,900 lbf).

Variants

GSLV rockets using the Russian Cryogenic Stage (CS) are designated as the GSLV Mk I while versions using the indigenous Cryogenic Upper Stage (CUS) are designated the GSLV Mk II.[21] All GSLV launches have been conducted from the Satish Dhawan Space Centre in Sriharikota.

GSLV Mark I

The first developmental flight of GSLV Mark I had a 129 tonne (S125) first stage and was capable of launching around 1500 kg into geostationary transfer orbit. The second developmental flight replaced the S125 stage with S139. It used the same solid motor with 138 tonne propellant loading. The chamber pressure in all liquid engines were enhanced, enabling a higher propellant mass and burn time. These improvements allowed GSLV to carry an additional 300 kg of payload.[22][23] The fourth operational flight of GSLV Mk I, GSLV-F06, has a 15 tonne propellant loading in the third stage, called the C-15.[24]

GSLV Mark II

This variant uses an Indian cryogenic engine, the CE-7.5, and is capable of launching 2500 kg into geostationary transfer orbit. Previous GSLV vehicles (GSLV Mark I) have used Russian cryogenic engines.[25]

For launches from 2018 a 6% increased thrust version of the Vikas engine was developed. It was demonstrated on 29 March 2018 in the GSAT 6A launch second stage. It will be used for the four Vikas engines first stage boosters on future missions.[26]

Launch statistics

Launch history

GSLV Mk I

Flight No. Date / time (UTC) Rocket,
Configuration		 Launch site Payload Payload mass Orbit User Launch
outcome
D1 18 April 2001
10:13		 Mk I First Launch Pad GSAT-1 1540 kg GTO INSAT Partial failure
Developmental flight, payload placed into lower than planned orbit, and did not have sufficient fuel to reach a usable orbit.[27] ISRO claims the launch to be successful.[28] In a 2014 interview, ISRO Chairman K. Radhakrishnan attributed the failure to incorrect mixture ratio used in the cryogenic upper stage.[29][27][30]
D2 8 May 2003
11:28		 Mk I First Launch Pad GSAT-2 1825 kg GTO INSAT Success
Developmental flight.[31]
F01 20 September 2004
10:31		 Mk I First Launch Pad GSAT-3 1950 kg GTO INSAT Success
First operational flight.[32]
F02 10 July 2006
12:08		 Mk I Second Launch Pad INSAT-4C 2168 kg GTO INSAT Failure
Both rocket and satellite had to be destroyed over the Bay of Bengal after the rocket's trajectory veered outside permitted limits.
F04 2 September 2007
12:51		 Mk I Second Launch Pad INSAT-4CR 2160 kg GTO INSAT Partial failure
Apogee lower and inclination higher than expected, due to an error in the guidance subsystem.[33] Eventually the 2160 kg payload reached the designated geostationary transfer orbit.[34][35] Minor error in orbit inclination corrected by satellite mission operators. Satellite is fully operational and full design life of ten years will be achieved. It completed 6 years in orbit successfully.[36] ISRO claims this GSLV flight to be successful.[37]
F06 25 December 2010
10:34		 Mk I Second Launch Pad GSAT-5P 2310 kg GTO INSAT Failure
First flight of GSLV Mk.I (c). Destroyed by range safety officer after loss of control over liquid-fueled boosters.[38]

GSLV Mk II

Flight No. Date / time (UTC) Rocket,
Configuration		 Launch site Payload Payload mass Orbit User Launch
outcome
D3 15 April 2010
10:57		 Mk II Second Launch Pad GSAT-4 2220 kg GTO INSAT Failure
First flight test of the ISRO designed and built Cryogenic Upper Stage (CUS). Failed to reach orbit due to malfunction of the Fuel Booster Turbo Pump (FBTP) of the cryogenic upper stage.[39]
D5 5 January 2014
10:48		 Mk II Second Launch Pad GSAT-14 1980 kg GTO INSAT Success
The flight was scheduled for 19 August 2013, but one hour and 14 minutes before the lift off, a leakage was reported and the launch was halted.[40]

Second flight of GSLV with indigenous cryogenic upper stage (CUS) developed by ISRO's Liquid Propulsion Systems Centre (LPSC) was launched successfully on 5 January 2014.[41][42] It was a launch with precision of 40 metres (130 ft). All the three stages performed successfully.[43][44] This was the first successful flight of the cryogenic stage which was developed indigenously in India.[45][46][47]

D6 27 August 2015
11:22		 Mk II Second Launch Pad GSAT-6 2117 kg GTO INSAT Success
GSLV Mk II D6 with an Indigenous Cryogenic Engine (ICE) successfully ferried GSAT-6 payload into Geostationary Transfer Orbit (GTO) with injection parameters of 170 km x 35945 km, 19.96 degree inclination. The cuboid-shaped GSAT-6 satellite includes a technology demonstrator S-Band unfurlable antenna with a diameter of six metre which will provide S-band communication services during its expected mission life of nine years.[48][49][50]
F05 8 September 2016
11:20		 MK II Second Launch Pad INSAT-3DR 2211  kg GTO INSAT Success
First operational flight of GSLV Mk II.

The injection parameters were met with extreme precision. Perigee was within 300m (within 0.18%) of the expected value whereas apogee was within 0.2% (80 km). The difference between expected and actual inclination degree was 0.

INSAT-3DR is an advanced atmospheric weather satellite. as well as the second heaviest satellite placed in orbit by an indigenous cryogenic engine propelled GSLV [51][52][53]

F09 5 May 2017
11:27		 Mk II Second Launch Pad GSAT-9 / South Asia Satellite 2230 kg GTO INSAT Success
South Asia Satellite was previously named as SAARC Satellite[54][55][56][57]
F08 29 March 2018
11:26		 Mk II Second Launch Pad GSAT-6A 2140 kg GTO INSAT Success
Used an enhanced version of the Vikas engine called High Thrust Vikas Engine (HTVE) which had a thrust of 848 kN in GS2 stage. Electro-hydraulic Actuation used for gimballing in GS2 stage was replaced by more reliable Electro-Mechanical Actuation.[58] Even though the launch was a success, communication was lost with the satellite 48 hours after launch.[59][60][61][62][63][64]
F11 19 December 2018
10:40		 Mk II Second Launch Pad GSAT-7A 2250 kg GTO INSAT Success
Used an enhanced version of the Vikas engine called High Thrust Vikas Engine (HTVE) along with uprated cryogenic engine C15.[65][66][67][68][69]


Planned launches
Date / time (UTC) Rocket,
Configuration		 Launch site Payload Orbit User
TBD Mk II Second Launch Pad GISAT 1
2268 kg[70][71][72][73][74]
August 2020[65][75][76][77] Mk II Second Launch Pad GISAT 2
2300 kg[78][70]
2020 Mk II Second Launch Pad GSAT-32
[79][70]
Late 2020 Mk II Second Launch Pad IDRSS-1 GTO ISRO
[80]
2020[65] Mk II Second Launch Pad GSAT-7C
[81]
2020[65] Mk II Second Launch Pad GSAT-7R
Replacement satellite for Indian Navy's GSAT-7.[82]
2021 Mk II Second Launch Pad IDRSS-2 GTO ISRO
[80]
September 2022[65] Mk II Second Launch Pad NISAR NASA / ISRO
NASA / ISRO collaboration[83]
2022[65] Mk II Second Launch Pad Insat 3DS
gollark: The correct political/economic system is me as supreme world dictator. I would work something good out probably.
gollark: YOU will be transported to Brazil.
gollark: You can simulate quantum computers on classical computers. It's just very slow.
gollark: Real time conversation rate is maybe 40 WPM which is, according to my calculator, about 25 times faster than that, so there may be difficulties.
gollark: Obviously that isn't very fast and you'd want to run the candles at a greater baud rate or put some in parallel.

See also

References
  1. "GAO".
  2. "Geosynchronous Satellite Launch Vehicle". Archived from the original on 21 October 2015. Retrieved 21 December 2014.
  3. "ISRO developing vehicle to launch small satellites". Retrieved 29 August 2018.
  4. "GSLV F09 Brochure". ISRO.
  5. "GSLV F08 Brochure". ISRO.
  6. "GSLV F11 Brochure". ISRO.
  7. "GSLV Launched Successfully" (PDF). Current Science. 80 (10): 1256. May 2001. Retrieved 12 December 2013.
  8. Subramanian, T S (March 17–31, 2001). "The GSLV Quest". Frontline. Retrieved 12 December 2013.
  9. "GSLV Rocket, Billed 'Naughty Boy'". NDTV. Wayback Machine. Archived from the original on 11 February 2018. Retrieved 11 February 2018.
  10. Jacob Aron. "India's hefty 'naughty boy' rocket comes in from cold". New Scientist. Wayback Machine. Archived from the original on 11 February 2018. Retrieved 11 February 2018.
  11. Raj, N Gopal (21 April 2011). "The long road to cryogenic technology". The Hindu. Chennai, India. Retrieved 12 December 2013.
  12. Subramanian, T S (28 April – 11 May 2001). "The cryogenic quest". Frontline. Retrieved 13 December 2013.
  13. "Why ISRO's New Engine and Mk III Rocket Are Reasons to Forget 1990 Cryogenic Scandal". The Wire. Retrieved 10 February 2018.
  14. "GSLV-F04". ISRO. Archived from the original on 4 January 2014. Retrieved 15 December 2013.
  15. "GSLV-D2". ISRO. Archived from the original on 9 August 2013. Retrieved 15 December 2013.
  16. "GSLV D3". ISRO. Archived from the original on August 10, 2013. Retrieved November 27, 2013.
  17. "Evolution of Indian launch vehicle technologies" (PDF). Current Science. Retrieved January 27, 2014.
  18. "GSLV-D5". Archived from the original on 6 October 2014. Retrieved 4 January 2014.
  19. "ISRO's Cryogenic Stage Fails in Maiden Flight". Space News. Archived from the original on May 26, 2012. Retrieved November 27, 2013.
  20. "GSLV, PSLV flights put off". The Hindu. Chennai, India. 1 January 2010.
  21. "GSLV-D3/GSAT-4 Brochure" (PDF). ISRO. Archived from the original (PDF) on 7 February 2014. Retrieved 15 January 2014.
  22. R. V. Perumal; B. N. Suresh; D. Narayana Moorthi; G. Madhavan Nair (25 July 2001). "First developmental flight of geosynchronous satellite launch vehicle (GSLV-D1)" (PDF). Current Science. 81 (2): 167–174. Archived from the original (PDF) on 5 March 2016.
  23. R. V. Perumal; D. Narayana Moorthi; N. Vedachalam; G. Madhavan Nair (10 September 2003). "Second developmental flight of Geosynchronous Satellite Launch Vehicle" (PDF). Current Science. 85 (5): 597–601. Archived from the original (PDF) on 16 February 2018.
  24. "GSLV-F06". ISRO. Archived from the original on August 10, 2013. Retrieved 9 January 2014.
  25. Clark, Stephen (2010-10-12). "India may seek international help on cryogenic engine". SPACEFLIGHT NOW. Retrieved 15 July 2011. Besides the new upper stage, the GSLV Mk.2 launched in April was nearly identical to previous versions of the booster.
  26. Clark, Stephen (29 March 2018). "India tests upgraded engine tech in successful communications satellite launch". Spaceflight Now. Retrieved 30 March 2018.
  27. Kyle, Ed (28 December 2010). "Page 2 of 2: Comprehensive Orbital Launch Failure List". India (SLV/ASLV/PSLV/GSLV) Flight History by Variant/Year (1979–2010). Retrieved 14 August 2013.
  28. "Press Brief on GSLV-D1/GSAT-1". Indian Space Research Organisation. 24 April 2001.
  29. Ramachandran, R. (22 January 2014). "GSLV MkIII, the next milestone". Frontline.
  30. "Isro clears launch of GSLV-D5". Business Standard. 31 December 2013. Retrieved 20 January 2014.
  31. "GSLV-D2 Mission". ISRO. Archived from the original on March 14, 2009.
  32. "EDUSAT mission". ISRO. Archived from the original on March 18, 2009.
  33. Clark, Stephen (2 September 2007). "India's large satellite launcher returns to flight". Spaceflight Now.
  34. "INSAT-4CR successfully placed in orbit". Times of India. 2 September 2007.
  35. "GSLV-F04 Launch Successful – Places INSAT-4CR in orbit". ISRO. Archived from the original on March 1, 2009.
  36. "ISRO refutes INSAT-4CR `disappearance' story". Hindustan Times. Archived from the original on 2013-11-12.CS1 maint: BOT: original-url status unknown (link)
  37. "First manoeuvre to raise satellite's orbit". Sriharikota: The Hindu. Retrieved November 19, 2015.
  38. "Rocket failed after 45 seconds, says ISRO". Hindustan Times. 25 December 2010. Archived from the original on 26 December 2010. Retrieved 25 December 2010.
  39. "GSLV-D3 Failure Analysis Report". ISRO.
  40. "GSLV-D5 rocket launch delayed, countdown clock stopped due to leak in second stage". NDTV. Retrieved November 27, 2013.
  41. Varma, M. Dinesh (31 October 2013). "Another shot at GSLV with indigenous cryogenic engine". The Hindu. Chennai, India. Retrieved November 27, 2013.
  42. "Preparations in full swing for Dec 15 GSLV mission". Hindustan Times. Retrieved November 27, 2013.
  43. "GSAT-14 Separated". Twitter. January 5, 2014. Retrieved January 5, 2014.
  44. "Performance of Cryogenic stage of GSLV D5 normal. Ignition sustained". Twitter. January 5, 2014. Retrieved January 5, 2014.
  45. "Isro successfully launches indigenous cryogenic engine-powered GSLV-D5". The Times Of India. Retrieved 5 January 2014.
  46. "GSLV-D5-Success". ISRO. Archived from the original on 4 January 2014. Retrieved 5 January 2014.
  47. Subramanian, T.S. (5 January 2014). "GSLV-D5 Launch Success". Chennai, India: The Hindu. Archived from the original on 6 January 2014. Retrieved 5 January 2014.
  48. "ISRO's GSLV D-6 puts GSAT-6 satellite in orbit". The Hindu. 27 August 2015.
  49. "GSAT 6". Retrieved 1 July 2014.
  50. "GSAT-6 slated for March launch". Retrieved 27 August 2015.
  51. "Isro's desi cryo engine–powered GSLV-F05 places INSAT-3DR weather satellite in orbit – Times of India". Retrieved 2016-09-08.
  52. Clark, Stephen. "GSLV puts advanced Indian weather satellite in orbit – Spaceflight Now". Retrieved 2016-09-08.
  53. "GSLV-F05 lobs advanced weather satellite INSAT-3DR into orbit – The Hindu". Retrieved 2016-09-08.
  54. "Made in India South Asia Satellite to be launched on 5 May". Mint. PTI. 30 April 2017.
  55. "Official Press Release: GSLV Successfully Launches South Asia Satellite". Press Information Bureau. 5 May 2017.
  56. Sinha, Amitabh (6 May 2017). "South Asian diplomacy lifts off on 2230-kg ISRO satellite GSAT-9". The Indian Express.
  57. Clark, Stephen (6 May 2017). "India launches satellite linking its South Asian neighbors". Spaceflight Now.
  58. "GSLV F08-GSAT-6A Brochure- ISRO". www.isro.gov.in. Indian Space Research Organisation. Retrieved 29 March 2018.
  59. "Isro Loses communication with GSAT-6A-Economic Times". www.economictimes.indiatimes.com. Economic Times. Retrieved 1 April 2018.
  60. "Status Update of GSAT-6A - ISRO". www.isro.gov.in. Retrieved 2018-04-01.
  61. "Isro confirms losing contact with communication satellite GSAT-6A - Times of India". The Times of India. Retrieved 2018-04-01.
  62. "GSLV Successfully Launches GSAT-6A Satellite". Press Information Bureau. 29 March 2018.
  63. Stories, Prajasakti News. "29న జిఎస్‌ఎల్వీ- ఎఫ్‌08 ప్రయోగం". Prajasakti. Retrieved 2018-03-02.
  64. "GSLV-F08/GSAT-6A Mission - ISRO". 2017-11-18. Archived from the original on 2017-11-18. Retrieved 2018-04-02.
  65. Pietrobon, Steven (5 July 2018). "Indian Launch Manifest". Retrieved 11 July 2018.
  66. "India's 19 upcoming missions, and ISRO's Small Satellite Launch Vehicle (SSLV) | SpaceTech Asia". SpaceTech Asia. 2018-08-28. Retrieved 2018-08-29.
  67. "Isro lines up 3 rocket launches in two months - Times of India". The Times of India. Retrieved 2018-11-07.
  68. "19న నింగిలోకి జీఎస్‌ఎల్‌వీ-ఎఫ్ 11 రాకెట్ | Andhrabhoomi - Telugu News Paper Portal | Daily Newspaper in Telugu | Telugu News Headlines | Andhrabhoomi". www.andhrabhoomi.net. Retrieved 2018-12-03.
  69. "Isro's GSLV-F11/Gsat-7A mission successful, satellite meant for military applications placed in orbit - Times of India". The Times of India. Retrieved 2018-12-19.
  70. "Starting May, ISRO to launch a string of 'defence' satellites". Retrieved 2 April 2019.
  71. "GSLV Planned launch" (PDF). VSSC. Retrieved 22 December 2019.
  72. "इसरो जाकर सैटेलाइट लांचिग देखेंगी रांची की मृदुला". Dainik Jagran (in Hindi). Retrieved 2020-02-14.
  73. "GSLV-F10 / GISAT-1 - ISRO". www.isro.gov.in. Retrieved 2020-02-25.
  74. "The launch of GISAT-1 onboard GSLV-F10, planned for March 05, 2020, is postponed - ISRO". www.isro.gov.in. Retrieved 2020-03-04.
  75. D.S, Madhumati. "ISRO readies for a busy 2019". The Hindu. Retrieved 3 January 2019.
  76. "GSLV Project: Planned launches of GSLV" (PDF).
  77. "HAL hands over 50th set of L-40 stage of GSLV-MKII to ISRO". Zee News. 2020-02-28. Retrieved 2020-02-28.
  78. Krebs, Gunter. "GISAT 1, 2". Gunter's Space Page. Retrieved April 27, 2017.
  79. "India to launch GSAT-32 in October next year to replace GSAT-6A". Retrieved August 12, 2018.
  80. "New satellites will help Gaganyaan cre". Retrieved 6 January 2020.
  81. "Satellite control set to give drones more sting". Times Of India. 22 September 2018. Retrieved 22 September 2018.
  82. Pubby, Manu (2019-07-18). "Navy to buy Rs 1,589 crore satellite from ISRO". The Economic Times. Retrieved 2019-07-19.
  83. Krebs, Gunter. "NISAR". Gunter's Space Page. Retrieved April 27, 2017.

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.