The rocket after its launch from Sriharikota on Thursday. (Reuters)

Sriharikota, April 15: A 40-metre-tall rocket tumbled over the Bay of Bengal and crashed into the sea minutes after launch today, leaving unfulfilled India’s dream of achieving full self-reliance in ferrying satellites into parking slots high above the equator.

The sixth flight of India’s Geosynchronous Satellite Launch Vehicle (GSLV), and the first with an indigenously developed cryogenic engine powered by liquid oxygen and liquid hydrogen, failed five minutes into its flight.

As the three-stage rocket climbed, the third stage cryogenic engine failed to ignite, sending the GSLV-D3 rocket and its payload, a communications satellite called GSAT-4, tumbling into the Bay of Bengal. This is the second time a GSLV has failed. A Russian-built cryogenic engine had powered the previous GSLV flight that had failed in July 2006.

“Everything went fine till the end of the second stage,” said Indian Space Research Organisation (Isro) chairman K. Radhakrishnan. “The cryogenic engine has to provide half the velocity to inject the satellite into its transfer orbit. But we are not sure the cryogenic engine ignited. The vehicle started losing control and altitude and splashed into the sea,” Radhakrishnan, a Kerala-born engineer, said at the launch centre here this evening.

“It will take us two or three days to figure out how it happened and an in-depth analysis of why it happened before corrective steps,” Radhakrishnan said. “We are confident we should be ready with the second indigenous cryogenic engine within one year.”

The failure is a setback to Isro’s quest for total self-reliance in launching 2,500kg class geostationary satellites which are parked about 37,000km over the equator. It is also likely to delay Isro’s goal of launching a manned space mission.

All five previous GSLV flights used cryogenic engines supplied by Russia. Isro still has two more Russian engines acquired under a deal signed in the early-1990s. The space agency had designed the first cryogenic engine on today’s flight of GSLV-Mk-II to carry a 2,220kg GSAT-4 satellite. But a manned mission will require an even more powerful version of the GSLV-Mk-III, capable of carrying a 4,000kg satellite.

Although senior Isro officials had in the past articulated the possibility of a manned space mission by 2015, it is unlikely that the space agency will seek funds for such a manned programme before the indigenous cryogenic engine is proven.

A cryogenic engine — which uses liquid oxygen maintained at minus 183 degrees Centigrade and liquid hydrogen at minus 253 degrees Centigrade — is technologically far more challenging than conventional rocket engines that use solid or liquid propellants.

Inside the engine, the cryo-cooled oxygen and hydrogen need to be pumped using turbo-pumps running at 40,000 revolutions per minute. “It’s an enormous engineering and materials science challenge,” a senior Isro official had once remarked.

“It is a virtual floating tinderbox that needs to be handled like a newborn from start to finish,” said G. Ravindranath, the mission’s project director. Cryogenic rocket engine technology is available only with China, Japan, Russia, the US, and the European Space Agency.

Today’s launch vehicle and satellite together cost Rs 330 crore. But Isro has also spent an estimated Rs 335 crore to develop the indigenous cryogenic engine over the past 16 years.

While the engine had performed well during ground tests, firing continuously for more than 720 seconds as required during the flight, Radhakrishnan said it had to be tested on a real flight in which it fires in vacuum, for certification as a reliable rocket engine.

Since Isro has lined up 11 GSLV flights in the near future, it would be important to understand what went wrong and get an indigenous engine working at the earliest. The next two GSLV flights will use the remaining two Russian cryogenic engines.

“The indigenous cryogenic engine will lead to total self-reliance and bring down the cost of launching satellites. We are almost there,” Radhakrishnan said.

Asked if he was disappointed that his first flight as Isro chairman had resulted in a failure, Radhakrishnan quoted the Gita: “We do our job. Success or failure, we continue to work hard so that ultimately we meet with success.”