While all this was going on, work on SLV was gathering momentum. One of the first things Dhawan did after he joined was to appoint a project director for SLV." Sarabhai had set up one scientist for each stage. So my question was, who is in charge of the vehicle? No one." Dhawan asked Brahm Prakash to find a project director. He appointed Kalam.
With Dhawan’s arrival, ISRO began to involve the private sector in a big way. ‘'He decided that the space programme would become unmanageable if ISRO tried to do everything on its own," says V Siddhartha, who had headed the technology transfer operations. This has now grown into a major collaboration with 230 private companies making most of the components ISRO needs.
SLV had its first flight in 1979, but this failed. The second attempt was successful. Kalam recalls an incident: ‘'The press had to be addressed after the flight. When the flight failed, Dhawan went alone and told them that he was responsible for the failure. And when it succeeded, he was missing. He had left it to me to convey the news."
When Dhawan retired in 1984 and U R Rao took over, ISRO was working on another larger vehicle, capable of putting a larger satellite (150 kg compared to 35 kg of the SLV) into a similar orbit. But it did not design a new vehicle. It took the SLV and put two strap-on boosters, and called it the Augmented Satellite Launch Vehicle.
Although the ASLV’s flight in 1987 was a disaster, ISRO was not unduly upset. After all, the SLV had also failed initially. But the second ASLV failure in 1988 came as a shock.
Doubts began to be expressed about the ability of the launch vehicle programme to proceed beyond the SLV stage. But ISRO’s characteristic resilience came to its aid. An enquiry committee was formed with Narasimha as the head. This choice of an outsider was itself unique."I announced in ISRO that anyone was free to come and give me his opinion," says Narasimha. After nine months of enquiry, the committee zeroed in on the problem.
It was due to a combination of factors. The configuration had made the vehicle difficult to control. During flight, some parameters deviated from the expected values far too much. Any normal vehicle would have corrected itself if any such deviation occurred, but this did not happen because of a fault, which was not detected despite numerous reviews. The winds in the upper atmosphere were also stronger than normal, and had caught the engineers unawares.
After the committee submitted its report, many changes were made in ASLV and every aspect of the vehicle was reviewed thoroughly. The next two flights (1992 and 1994) were successful. ‘'The ASLV failure was the reason for all the subsequent successes of ISRO,’' says Rao.
The next stage, the Polar-Satellite Launch Vehicle was to be another giant leap technologically. At take off, the rocket weighed 283 tonnes, compared to the 17 tonnes of SLV. It was to put an 800 kg satellite at a height of 820 km. Although the design of PSLV was completed in the mid-eighties, it called for the development of a horde of new technologies. One of them was the liquid engine (second and fourth stage), which was developed with French assistance.
‘'The collaboration with the French started with a few casual meetings,’' says A E Muthunayagam, who headed the liquid propulsion division in ISRO. "It later became a big project." Muthunayagam, now secretary of the department of ocean development, was another scientist Sarabhai had persuaded to return from the US.
But transfer of technology was not always as easy as the liquid engine (named the Vikas engine). In many cases, it was just not available. A particularly difficult material to develop was maraging steel, a kind of high-strength steel, not available anywhere. "People had heard only about the cryogenic embargo. But ISRO had had to work with several embargoes. Even when there were no embargoes, licences would not be given," says Rao.
Some of these bordered on the ridiculous. The PSLV is moved to the launch pad on a 72 metre tall moving tower which has 16 big wheels. Though not a complex technology, ISRO found no country willing to sell these wheels. So ISRO had to make them on its own. It cost a fortune because large casting facilities had to be set up for making them.
The PSLV flew finally in 1993, but the mission failed because of a minor software error. Before Monday's flight, PSLV had two subsequent flights, in 1994 and 1996, both of which were successful. Using PSLV, India can now launch its remote sensing satellite. In fact, India can now enter the commercial market for such launches.
An era will end when the GSLV is launched in 1998; then, all that Sarabhai had wanted would be fulfilled. But the space programme will continue with better launch vehicles and satellites. Nearing the 21st century, ISRO now finds that it has to tackle new problems. One of the strengths of ISRO has been its youth. Over the years, the average age of its scientists has increased, with most of them now in their forties and fifties. ISRO chairman K Kasturirangan plans to set this anomaly right with an infusion of young scientists to replace the around thousand scientists nearing retirement.
With the induction of fresh blood, ISRO is likely to find itself taking on new challenges.
-- P Hari
Kind courtesy: BusinessWorld
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