Editing Polar Satellite Launch Vehicle (section)

== Development ==
[[File:PSLV-C11 Strapon01.jpg|thumb|290px|left|PSLV-C11 strap-on]]

Studies by the PSLV Planning group under [[S. Srinivasan|S Srinivasan]] to develop a vehicle capable of delivering a 600&nbsp;kg payload to a 550&nbsp;km [[sun-synchronous orbit]] from [[Satish Dhawan Space Centre|SHAR]] began in 1978.<ref>{{Cite book|title=Ready to Fire: How India and I survived the ISRO Spy case|publisher=Bloomsbury Publishing|year=2018|pages=203}}</ref><ref>{{Cite book|title=From Fishing Hamlet to Red Planet|publisher=ISRO|pages=173}}</ref> Among 35 proposed configurations, four were picked; by November 1980, a vehicle configuration with two strap-ons on a core booster (S80) with 80 tonne solid propellant loading each, a liquid stage with 30 tonne propellant load (L30), and an upper stage called the Perigee-Apogee System (PAS) was being considered.<ref>{{cite news|url=https://books.google.com/books?id=IbbMj56ht8sC&pg=PA215|title=Indian ambitions in space go sky-high|date=22 January 1981|publisher=New Scientist|page=215|access-date=30 December 2018|archive-date=10 October 2022|archive-url=https://web.archive.org/web/20221010090941/https://books.google.com/books?id=IbbMj56ht8sC&pg=PA215|url-status=live}}</ref><ref name=":1">{{cite book|title=A brief history of rocketry in ISRO|last1=Rao|first1=P.V. Monoranjan|last2=Radhakrishnan|first2=Paramaswaran|publisher=Orient Blackswan|year=2012 |isbn=978-8173717642|pages=215}}</ref><ref name=":3">{{cite book|title=From fishing hamlet to red planet|publisher=Harpercollins|year=2015|isbn=978-9351776895|editor-last=Rao|editor-first=P.V. Manoranjan |chapter=2.6 PSLV: The workhorse of ISRO by N. Narayanamoorthy}}</ref><ref>{{cite book|title=Reach For the Stars: The Evolution of India's Rocket Programme|last=Raj|first=Gopal|publisher=Viking|year=2000 |isbn=978-0670899500|chapter=8. PSLV: Achieving Operational Launch Capability|quote=About a year later, an important change was made, with the solid fourth stage being substituted by a liquid stage. This change was considered necessary since the accuracy with which the IRS satellites had to be put into orbit — within 15 km in terms of orbital height and within 0.1° of the desired orbital inclination — could not be achieved with a solid stage.}}</ref>

By 1981, confidence grew in [[Remote sensing satellites|remote sensing spacecraft]] development with the launch of [[Bhaskara (satellite)|Bhaskara-1]], and the PSLV project objectives were upgraded to have the vehicle deliver a 1000&nbsp;kg payload into a 900&nbsp;km [[Sun-synchronous orbit|SSO]]. As technology transfer of [[Viking (rocket engine)|Viking]] rocket engine firmed up, a new lighter configuration with the inclusion of a liquid powered stage was selected.<ref>{{Cite book|title=Ready To Fire: How India and I Survived the ISRO Spy Case|publisher=Bloomsbury Publishing|year=2018|pages=207–208}}</ref> Funding was approved in July 1982 for the finalized design, employing a single large S125 solid core as first stage with six 9 tonne strap-ons (S9) derived from the [[Satellite Launch Vehicle|SLV-3]] first stage, liquid fueled second stage (L33), and two solid upper stages (S7 and S2.) This configuration needed further improvement to meet the orbital injection accuracy requirements of IRS satellites, and hence, the solid terminal stage (S2) was replaced with a pressure fed liquid fueled stage (L1.8 or LUS) powered by twin engines derived from roll control engines of the first stage. Apart from increasing precision, liquid upper stage also absorbed any deviation in performance of solid third stage. The final configuration of [[PSLV-D1]] to fly in 1993 was (6 × S9 + S125) + L37.5 + S7 + L2.<ref name=":1"/><ref name=":3"/>

The [[inertial navigation system]]s are developed by [[ISRO Inertial Systems Unit]] (IISU) at [[Thiruvananthapuram]]. The liquid propulsion for the second and fourth stages of the PSLV as well as the [[Reaction control system]]s (RCS) are developed by the [[Liquid Propulsion Systems Centre]] (LPSC) at [[Valiamala]] near [[Thiruvananthapuram]], [[kerala]]. The solid [[Solid-propellant rocket|propellant motor]]s are processed at [[Satish Dhawan Space Centre]] (SHAR) at [[Sriharikota]], [[Andhra Pradesh]], which also carries out launch operations. The aerodynamic characterization research was conducted at the [[National Aerospace Laboratories]]' 1.2m Trisonic Wind Tunnel Facility.<ref>{{Cite web |date=2022-06-06 |title=Bengaluru: 1.2m trisonic wind tunnel at National Aerospace Laboratories completes 55 years of service |url=https://www.aninews.in/news/national/general-news/bengaluru-12m-trisonic-wind-tunnel-at-national-aerospace-laboratories-completes-55-years-of-service20220606001500/ |access-date=2024-11-22 |website=ANI |language=en}}</ref>

The PSLV was first launched on 20 September 1993.<ref>{{Cite web |title=PSLV - ISRO |url=https://www.isro.gov.in/launchers/pslv |access-date=2022-03-09 |website=www.isro.gov.in |archive-date=9 February 2020 |archive-url=https://web.archive.org/web/20200209203227/https://www.isro.gov.in/launchers/pslv |url-status=live }}</ref><ref name=":4" /> The first and second stages performed as expected, but an [[Spacecraft attitude control|attitude control]] problem led to the collision of the second and third stages at separation, and the payload failed to reach orbit.<ref>{{cite web|title=India (Launchers)|url=http://claudelafleur.qc.ca/Indians-launchers.html|publisher=Spacecraft Encyclopedia|access-date=12 November 2014|archive-date=20 May 2016|archive-url=https://web.archive.org/web/20160520142430/http://claudelafleur.qc.ca/Indians-launchers.html|url-status=live}}</ref> After this initial setback, the PSLV successfully completed its second mission in 1994.<ref>{{cite web|title=PSLV (1)|url=http://space.skyrocket.de/doc_lau_det/pslv_1.htm|publisher=Gunter's Space Page|access-date=12 November 2014|archive-date=5 December 2020|archive-url=https://web.archive.org/web/20201205170455/https://space.skyrocket.de/doc_lau_det/pslv_1.htm|url-status=live}}</ref> The fourth launch of PSLV suffered a partial failure in 1997, leaving its payload in a lower than planned orbit. In November 2014, the PSLV had launched 34 times with no further failures.<ref>{{cite web|title=PSLV|url=http://space.skyrocket.de/doc_lau/pslv.htm|website=Gunter's Space Page|access-date=12 November 2014|archive-date=24 July 2011|archive-url=https://web.archive.org/web/20110724081813/http://space.skyrocket.de/doc_lau/pslv.htm|url-status=live}}</ref> (Although launch 41: August 2017 PSLV-C39 was unsuccessful.<ref name="pslv"/>)

PSLV continues to support Indian and foreign satellite launches especially for [[low Earth orbit]] (LEO) satellites. It has undergone several improvements with each subsequent version, especially those involving thrust, efficiency as well as weight. In November 2013, it was used to launch the [[Mars Orbiter Mission]], India's first interplanetary probe.<ref>{{Cite web|url=http://www.isro.org/satellites/mars-orbiter-spacecraft.aspx|title=ISRO - Mars Orbiter Mission|access-date=2014-04-08|archive-date=27 October 2014|archive-url=https://web.archive.org/web/20141027123201/http://www.isro.org/satellites/mars-orbiter-spacecraft.aspx|url-status=live}}</ref>

In June 2018, the Union Cabinet approved {{INRconvert|6131|c|lk=on|year=2020}} for 30 operational flights of the PSLV scheduled to take place between 2019 and 2024.<ref>{{cite web|title=Government approves Rs 10,000-crore continuation programmes for PSLV, GSLV|url=https://economictimes.indiatimes.com/news/science/government-approves-rs-10000-crore-continuation-programmes-for-pslv-gslv/articleshow/64483323.cms|publisher=The Economic Times|date=7 June 2018|access-date=8 June 2018|archive-date=8 June 2018|archive-url=https://web.archive.org/web/20180608035934/https://economictimes.indiatimes.com/news/science/government-approves-rs-10000-crore-continuation-programmes-for-pslv-gslv/articleshow/64483323.cms|url-status=live}}</ref>

ISRO is working towards handing over the production and operation of PSLV to private industry through a joint venture.<ref>{{Cite web |title=Press Release - NSIL signs Contract with HAL (lead member of HAL-L&T consortium) for production of 05 nos of PSLV-XL |url=https://www.nsilindia.co.in/sites/default/files/Press%20Release-%20Contract%20signed%20for%20production%20of%2005%20nos%20PSLV-XL.pdf |archive-url=https://web.archive.org/web/20220909125437/https://www.nsilindia.co.in/sites/default/files/Press%20Release-%20Contract%20signed%20for%20production%20of%2005%20nos%20PSLV-XL.pdf |archive-date=9 September 2022}}</ref> On 16 August 2019, [[NewSpace India Limited]] issued an [[invitation to tender]] for manufacturing PSLV entirely by private industries.<ref>{{Cite news |last=D.s |first=Madhumathi |date=2019-08-16 |title=ISRO's business arm begins search for PSLV makers |language=en-IN |work=The Hindu |url=https://www.thehindu.com/news/national/new-isro-arm-begins-search-for-pslv-makers/article29112870.ece |access-date=2022-09-09 |issn=0971-751X |archive-date=9 September 2022 |archive-url=https://web.archive.org/web/20220909133320/https://www.thehindu.com/news/national/new-isro-arm-begins-search-for-pslv-makers/article29112870.ece |url-status=live }}</ref><ref>{{Cite web |author=Chethan Kumar |date=Aug 27, 2021 |title=Adani, L&T among those in race for PSLV contract {{!}} India News - Times of India |url=https://timesofindia.indiatimes.com/india/adani-lt-in-race-for-deal-to-make-space-launch-vehicles/articleshow/85674630.cms |access-date=2022-09-09 |website=The Times of India |language=en |archive-date=9 September 2022 |archive-url=https://web.archive.org/web/20220909133322/https://timesofindia.indiatimes.com/india/adani-lt-in-race-for-deal-to-make-space-launch-vehicles/articleshow/85674630.cms |url-status=live }}</ref> On 5 September 2022, [[NewSpace India Limited]] signed a contract with [[Hindustan Aeronautics Limited]] and [[Larsen & Toubro]] led conglomerate for the production of five PSLV-XL launch vehicles after they won competitive bidding. Under this contract, they have to deliver their first PSLV-XL within 24 months and the remaining four vehicles every six months.<ref>{{Cite news |title=HAL-L&T to build five PSLV rockets, bags Rs 860 crore deal from NSIL for the project |work=The Economic Times |url=https://economictimes.indiatimes.com/industry/indl-goods/svs/engineering/hal-lt-to-build-five-pslv-rockets-bags-rs-860-crore-deal-from-nsil-for-the-project/articleshow/93980649.cms |access-date=2022-09-09 |archive-date=9 September 2022 |archive-url=https://web.archive.org/web/20220909133332/https://economictimes.indiatimes.com/industry/indl-goods/svs/engineering/hal-lt-to-build-five-pslv-rockets-bags-rs-860-crore-deal-from-nsil-for-the-project/articleshow/93980649.cms |url-status=live }}</ref><ref>{{Cite news|date=2017-10-26|title=ISRO looks at JV for PSLV manufacture; launch to be privatized by 2020|publisher=Geospatial World|url=https://www.geospatialworld.net/blogs/isro-looks-jv-pslv-manufacture-launch-privatized-2020/|access-date=2017-10-26|archive-date=16 November 2017|archive-url=https://web.archive.org/web/20171116011358/https://www.geospatialworld.net/blogs/isro-looks-jv-pslv-manufacture-launch-privatized-2020/|url-status=live}}</ref><ref>{{Cite web |author=Chethan Kumar |date=Apr 9, 2022 |title=Hal-l&t Wins Over 824-cr Contract For Making 5 Pslvs {{!}} India News - Times of India |url=https://timesofindia.indiatimes.com/india/hal-lt-wins-over-824-cr-contract-for-making-5-pslvs/articleshow/90736339.cms |access-date=2022-09-09 |website=The Times of India |language=en |archive-date=9 September 2022 |archive-url=https://web.archive.org/web/20220909133320/https://timesofindia.indiatimes.com/india/hal-lt-wins-over-824-cr-contract-for-making-5-pslvs/articleshow/90736339.cms |url-status=live }}</ref>