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Failures behind, GSLV-D5 ready to fire
CHENNAI: For the Indian Space Research Organization, time would stand virtually still for some 17 minutes after the GSLV-D5 blasts off from Sriharikota at 4.18pm on Sunday. For, those will be the moments that deliver the result of its 20-year toil to launch a heavy rocket with an indigenous cryogenic engine.
The countdown began at the Satish Dhawan Space Centre at 11.18am on Saturday. The 49.13-metre rocket with a liftoff mass of 414.75 tonnes will carry to space the 1,982kg GSAT-14 communication satellite with applications in education and healthcare.
After using up six out of the seven cryogenic engines India had bought from Russia, Isro was forced to develop its own engine. In the past three years, which saw two failures - in April 2010 and December 2010 - and an abortion of the GSLV launch in August 2013, hundreds of Isro scientists spent thousands of hours doing tests and making alterations to components of the rocket. Sunday's performance would decide the fate of several of India's ambitious space programmes, including manned missions. "After all the tests, we are confident of a successful flight," Isro chairman K Radhakrishnan told TOI on the eve of the launch.
While India has mastered the PSLV range of rockets with a string of 25 consecutive successes, GSLV, which can carry heavier payloads, including humans, has remained a challenge. In April 2010, Isro tested its first indigenous cryogenic engine, but it failed less than a second after the cryogenic stage ignited. A refurbished GSLV-D5 was to be launched in August 2013, but a leak in the liquid fuel tank forced the mission to be aborted two hours before the rocket was to lift off. Cryogenics, the science of extremely low temperatures, has posed a challenge to rocket scientists across the world. Cryogenic engines use liquid hydrogen and oxygen.
From the April 2010 failure, when the cryogenic engine failed 800 milliseconds after ignition, Isro learned that dissimilar contractions of different materials led to problems in three bearings in the fuel booster turbo pump. "Here we made some changes to the design of one of the casings and tested the new pump under normal operating temperatures. Its working perfect now," Radhakrishnan said. In the case of the December 2010 misfire, scientists found some Russian connectors had snapped. This was corrected by changing the mounting design, which was later tested on ground using the wind tunnel blow down method.
"We have thoroughly studied the past experiences and made changes. We are all upbeat," said Radhakrishnan while travelling from the Isro headquarters in Bangalore to Sriharikota on Saturday.
The Sriharikota launchpad became active after the mission readiness review team and the launch authorization board cleared the launch on December 28, 2013. Soon the vehicle was moved from the vehicle assembly building to the umbilical tower.
India's ambitious future space programmes, including interplanetary explorations and manned missions, rest on the shoulders of GSLV. A successful flight of GSLV-D5 on Sunday would be a morale booster for Isro and the best promise for bigger space ventures.
Link - Failures behind, GSLV-D5 ready to fire - The Times of India
Keeping fingers crossed for you ISRO. Good Luck!
CHENNAI: For the Indian Space Research Organization, time would stand virtually still for some 17 minutes after the GSLV-D5 blasts off from Sriharikota at 4.18pm on Sunday. For, those will be the moments that deliver the result of its 20-year toil to launch a heavy rocket with an indigenous cryogenic engine.
The countdown began at the Satish Dhawan Space Centre at 11.18am on Saturday. The 49.13-metre rocket with a liftoff mass of 414.75 tonnes will carry to space the 1,982kg GSAT-14 communication satellite with applications in education and healthcare.
After using up six out of the seven cryogenic engines India had bought from Russia, Isro was forced to develop its own engine. In the past three years, which saw two failures - in April 2010 and December 2010 - and an abortion of the GSLV launch in August 2013, hundreds of Isro scientists spent thousands of hours doing tests and making alterations to components of the rocket. Sunday's performance would decide the fate of several of India's ambitious space programmes, including manned missions. "After all the tests, we are confident of a successful flight," Isro chairman K Radhakrishnan told TOI on the eve of the launch.
While India has mastered the PSLV range of rockets with a string of 25 consecutive successes, GSLV, which can carry heavier payloads, including humans, has remained a challenge. In April 2010, Isro tested its first indigenous cryogenic engine, but it failed less than a second after the cryogenic stage ignited. A refurbished GSLV-D5 was to be launched in August 2013, but a leak in the liquid fuel tank forced the mission to be aborted two hours before the rocket was to lift off. Cryogenics, the science of extremely low temperatures, has posed a challenge to rocket scientists across the world. Cryogenic engines use liquid hydrogen and oxygen.
From the April 2010 failure, when the cryogenic engine failed 800 milliseconds after ignition, Isro learned that dissimilar contractions of different materials led to problems in three bearings in the fuel booster turbo pump. "Here we made some changes to the design of one of the casings and tested the new pump under normal operating temperatures. Its working perfect now," Radhakrishnan said. In the case of the December 2010 misfire, scientists found some Russian connectors had snapped. This was corrected by changing the mounting design, which was later tested on ground using the wind tunnel blow down method.
"We have thoroughly studied the past experiences and made changes. We are all upbeat," said Radhakrishnan while travelling from the Isro headquarters in Bangalore to Sriharikota on Saturday.
The Sriharikota launchpad became active after the mission readiness review team and the launch authorization board cleared the launch on December 28, 2013. Soon the vehicle was moved from the vehicle assembly building to the umbilical tower.
India's ambitious future space programmes, including interplanetary explorations and manned missions, rest on the shoulders of GSLV. A successful flight of GSLV-D5 on Sunday would be a morale booster for Isro and the best promise for bigger space ventures.
Link - Failures behind, GSLV-D5 ready to fire - The Times of India
Keeping fingers crossed for you ISRO. Good Luck!
