Explained: ISRO’s SSLV, a small satellite launcher with big prospects ahead

The SSLV is intended to cater to a market for the launch of small satellites into low earth orbits which has emerged in recent years on account of the need for developing countries, private corporations, and universities for small satellites.

The launch of small satellites has until now been dependent on ‘piggy-back’ rides with big satellite launches on ISRO’s work-horse – the Polar Satellite Launch Vehicle which has had over 50 successful launches so far. The launch of small satellites as a consequence has been dependent on the finalising of launch contracts for the larger satellites by ISRO.

The launch of small satellites has until now been dependent on ‘piggy-back’ rides with big satellite launches on ISRO’s work-horse – the Polar Satellite Launch Vehicle. (Photo: PTI)

Somanath himself is credited with the design and development of the SSLV during his time as director of the Vikram Sarabhai Space Centre in Thiruvananthapuram since 2018. The launch of the maiden flight of the SSLV was scheduled for July 2019 but has been delayed due to setbacks from the Covid 19 crisis and other issues.

The SSLV can carry satellites weighing up to 500 kg to a low earth orbit while the tried and tested PSLV can launch satellites weighing in the range of 1000 kg.

“The SSLV is the smallest vehicle at 110-ton mass at ISRO. It will take only 72 hours to integrate, unlike the 70 days taken now for a launch vehicle. Only six people will be required to do the job, instead of 60 people. The entire job will be done in a very short time and the cost will be only around Rs 30 crore. It will be an on-demand vehicle,” former ISRO chairman K Sivan had stated in 2019 at the ISRO headquarters during an annual press conference.

The former chairman Sivan said in an industry meeting that year that about 15 to 20 SSLVs would be required every year to meet the national demand alone.

The SSLV received a commercial booking in 2019 itself from the US space launch services intermediary Spaceflight Inc. Spaceflight announced on August 8, 2019, that it has clinched a deal with an ISRO commercial arm for using the second developmental flight of the SSLV rocket to launch a spacecraft for an “undisclosed US-based satellite constellation” customer.

“SSLV is perfectly suited for launching multiple microsatellites at a time and supports multiple orbital drop-offs. We are excited to add SSLV to our launch portfolio and manage many launches together — first to LEO (low earth orbit) mid-inclinations this year and SSO missions starting in the fall of 2020,” Spaceflight CEO and president Curt Blake said in 2019.

The development and manufacture of the SSLV are expected to create greater synergy between the space sector and private Indian industries – a key aim of the space ministry. Indian industry has a consortium for the production of PSLV and should come together to produce the SSLV as well once it is tested, ISRO has stated in the past.

One of the aims of the newly-created ISRO commercial arm, New Space India Limited (NSIL), is to use research and development carried out by ISRO over the years for commercial purposes through Indian industry partners.

“Manufacturing and production of Small Satellite Launch Vehicle (SSLV) and Polar Satellite Launch Vehicle (PSLV) through technology transfer,” is one of the mandates of the new firm.

There are more than 500 industries contributing to ISRO programs at present, and more than half of the project budget outlay for space programs flows to these industries.

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