Watch: ISRO completes crucial test of Solid Rocket Booster for human spaceflight

Sriharikota, IndiaWritten By: Sidharth MPUpdated: May 13, 2022, 06:02 PM IST
main img

Story highlights

The rocket booster is being modified and tested to be safe and suitable for carrying humans to space, as part of India's Gaganyaan Human Spaceflight programme.

Indian Space Research Organization (ISRO) successfully completed the maiden static test fire of its 'HS200' rocket booster, at 7:20am on Friday at the Satish Dhawan Space Centre in Sriharikota. This booster is a modified, human-rated version of the existing 'S200' booster that is used on the Indian space agency's heaviest rocket, the GSLV Mk3. Friday's test is in line with the human-rating process, where the agency modifies the GSLV Mk3 rocket and its components for carrying astronauts. Simply put, the GSLV Mk3 rocket is a cargo-hauler, meant to take satellites to space. Now, it is being modified and tested to be safe and suitable for carrying humans to space, as part of India's Gaganyaan Human Spaceflight programme.

WION spoke to Dr. S. Unnikrishnan Nair, Director, Vikram Sarabhai Space Centre (VSSC) to understand the significance of the test. VSSC is the lead Centre of Indian Space Research Organisation (ISRO) and pioneers in rocket research and launch vehicle projects of ISRO.

According to Dr. Nair, their teams had been working on making changes to the S200 rocket booster since 2019 and had improvised right from small components such as ignitors, digital control electronics and even went on to develop ISRO's largest electro-mechanical actuators. In this case, the electro-mechanical actuator will be used to steer the S200 booster's thrust and eventually the rocket's travel, by adjusting the nozzle's direction. Friday's ground test involved the static firing of one solid booster for a duration of 135 seconds.


"Reducing chamber pressure, ensuring leak-proofness, robustness, higher margins, etc. are some of the changes we had made to the S200, to increase its reliability, as part of human-rating process" Dr. Nair said, when queried about the difference between the existing S200 and the human-rated version. He also added that nearly 700 parameters (such as chamber pressure, thrust, shock, vibration etc.) were monitored during the test and how everything turned out perfect. However, he said that the entire set of data would have to be closely examined to determine if another test of the same booster would be required.

The GSLV Mk3 is a three-stage rocket, where the first stage(S200) is powered by solid-fuel, the second stage(L110) is powered by liquid fuel and the third (C25 Cryogenic stage) is powered by liquid hydrogen and liquid oxygen. In a rocket such as this, the stages function like runners in a relay race. The first stage performs its part and then hands over the task to the second, the second performs its part and then hands over the task to the third. Finally, the third stage performs its task and injects the payload (satellite or human-carrying capsule) into the desired orbit.

Notably, out of the three propulsion stages of GSLV Mk3, the human rated versions of second stage known as L110-G (loaded with liquid propellant) and the third stage C25-G (with cryogenic propellant) are in the final phase of qualification including tests with static firing. 

The HS200 booster test fired on Friday was loaded with 203 tons of solid propellant, the booster measures 20meters in length and 3.2meters in diameter. It is the world’s 2nd largest operational booster that is fuelled by solid propellant. With the successful completion of this test, ISRO marches one more step closer to Gaganyaan Programme.

ISRO has been working on the ambitious Gaganyaan mission that involves demonstrating indigenous capability to undertake human space flight mission to Low Earth Orbit and will lay the foundation for a sustained Indian human space exploration programme in the long run. As part of this programme, two unmanned missions and one manned mission are approved by Government of India.