PSLV Rocket: 1 To 60 In Three Decades

In terms of success rate, the PSLV rocket has an enviable record of 57 successful missions out of 58 commercial ones.

On December 30, 2024, India will fly its workhorse rocket Polar Satellite Launch Vehicle (PSLV) rocket coded as PSLV-C60 with two satellites that would carry out docking and undocking exercises in space.

Though the Indian Space Research Organisation (ISRO) has numbered the rocket as PSLV-C60 (C stands for commercial), it is actually the 59th PSLV rocket.

ISRO had skipped numbering a PSLV rocket as PSLV-C13 and went straight to PSLV-C14 after the PSLV-C12 rocket that was launched in April 2009.

The Indian space agency has also skipped the supposedly unlucky number 13 while numbering its other rocket Geosynchronous Satellite Launch Vehicle (GSLV).

Till date, ISRO has launched 61 PSLV rockets -- 58 commercial and three developmental ones.

While the four staged PSLV's first developmental flight in 1993 was a failure, the success lady began to smile on ISRO from 1994 onwards till date except twice -- a partial failure in 1997 and a total failure in 2017.

In terms of success rate, the PSLV rocket has an enviable record of 57 successful missions out of 58 commercial ones.

Over the years, ISRO used the PSLV rockets for orbiting not only Indian satellites but also about 350 foreign satellites for a fee.

ISRO had used the PSLV rocket for its interplanetary missions -- Chandrayaan-1 in 2008, the Mars Orbiter Spacecraft in 2013, the Sun mission, Aditya-L1 and for India's space observatory Astrosat.

According to ISRO, the PSLV earned its title 'the workhorse of ISRO' through consistently delivering various satellites into low earth orbits, particularly the IRS (Indian Remote Sensing) Series of satellites.

The PSLV has also been used to launch various satellites into Geosynchronous and Geostationary orbits, like satellites from the IRNSS Constellation.

The PSLV is capable of placing multiple payloads into orbit, thus multi-payload adaptors are used in the payload fairing.

The payload performance of the vehicle and mission flexibility is evident from the challenging missions where multi-orbit and multi-satellite missions are accomplished, the space agency said.

In 2017, the PSLV-C37 rocket scored a century by orbiting a record 104 satellites.

ISRO has developed five variants of PSLV rockets -- Standard, Core Alone, XL, DL and QL.

The use of one particular variant depends on the weight of the payload to be orbited.

The normal configuration of a PSLV rocket is a four stage/engine, powered by solid and liquid fuels alternatively with six booster motors strapped on to the first stage to give higher thrust during the initial flight moments.

The difference between the variants is the use or non-use of strap-on boosters depending on the payload weight.

Venkatachari Jagannathan can be reached at venkatacharijagannathan@gmail.com

Feature Presentation: Aslam Hunani/Rediff.com