SV Krishna Chaitanya By

Express News Service

CHENNAI: AT 5.28 pm on Monday, when the Indian Space Research Organisation (ISRO) launches indigenous rocket GSLV Mk III, it would be a culmination of 15 years of hard work by several Indian space scientists. But one man who deserves a special note is PV Venkitakrishnan, an IIT Madras alumnus and current director of ISRO Propulsion Complex, Mahendragiri in Tirunelveli.



Venkitakrishnan holds the record of being the only scientist who has been part of Mk III journey from its inception to realization. As a project manager, he was the person who prepared the report. He did his PhD in Mechanical Engineering and IIT Madras has recognised him with Distinguished Alumnus Award early this year.

With Mission Readiness Review committee and Launch Authorisation Board clearing the 25-and-a-half-hour countdown, Venkitakrishnan is set to enjoy the historic moment from the mission control room. GSLV Mk III D1/GSAT-19 will be launched from the second launchpad in Sriharikota. Speaking exclusively with Express, Venkitakrishnan said it was like his baby. “My baby is now attaining adulthood and will help India take another giant leap in space exploration.” Mk III is capable of carrying payloads up to 4,000 kg into Geosynchronous Tranfer Orbit (GTO) and 10,000 kg into Low Earth Orbit (LEO). Its payload in the current mission, GSAT-19, weighing 3,136 kg, will be the heaviest satellite being launched from India.

Venkitakrishnan says his journey has been fulfilling. Though, he was never in the limelight, people within ISRO acknowledge that it was he who started the ball rolling. For eight years between 2002 to 2010, he served as project manager and then as deputy project director of GSLV Mk III. “These were formative and crucial years. We had a small team, but managed to bring in all the necessary infrastructural development like furnace, large vertical lathes, testing rigs.

The two stages L110 and S200 were developed and qualified. When there were plans to have an experimental flight with passive cryogenic stage, I was posted to Liquid Propulsion Space Centre (LPSC), where I was entrusted with the job of developing indigenous cryogenic stage as engines were not coming from Russia.



“There was a strategic element — a superalloy — found in the inner lining of Russian engines and that is common for Mk II, Mk III and semi-cryo engines. From 2010-15, entire cryogenic engine for Mk III was developed, including materials, special steels, superalloys, investment castings and copper alloys. Everything was developed,” he recalled.

Later, Venkitakrishnan was posted as deputy director of Vikram Sarabhai Space Centre (VSSC), where he was leading the Mechanical and Materials Entity and achieved a major breakthrough. “We were using gas bottles submerged in oxygen tank. If the bottles can be submerged in hydrogen tank then more helium can be accommodated because hydrogen temperature is very low compared to oxygen temperature. Helium is the required gas for starting the engine. For this, I have Titanium Alpha alloys and able to cut down the required eight gas bottles to two. This has taken the payload capacity of GSLV Mk III to over 3 tonnes. Otherwise, it was supporting less than 3 tonnes. To commit to GSAT 19 that is being launched, it was an immediate requirement,” he explained.

Venkitakrishnan was posted as director of ISRO Propulsion Complex in December 2016. Here he successfully completed engine hot test and full duration test of the cryogenic stage in first attempt. “On April 27, we flagged-off the cryogenic stage to Sriharikota from Mahendragiri. That has completed the entire journey. From development of different stages, internal engines, manufacturing, outer tanks, structures, separation systems and alloy selections, I was part of every important moment,” he concluded.

Not just him, Venkitakrishnan’s wife V Brinda, head, Control Division, VSSC, also played an important role. She designed Digital Auto Pilot (DAP) for the GSLV Mk III. DAP called as the brain of a launch vehicle.

Control of such huge launch vehicle from lift-off till payload injection is achieved through digital autopilot.