It is almost a rite of passage that an Indian launch vehicle runs into trouble in its first flight. The country's very first attempt to launch a satellite failed in August 1979 when the SLV-3 rocket went out of control and ended up in the Bay of Bengal. A year later, those problems were sorted out and the rocket put a 35-kg Rohini satellite into orbit. The Indian Space Research Organisation had to cope with two successive failures with the Augmented Satellite Launch Vehicle (ASLV) before its third flight in 1992 went smoothly. In 1993, a series of technical shortcomings coalesced and the first flight of the Polar Satellite Launch Vehicle (PSLV) ended in failure. Those issues were swiftly resolved and the PSLV has become known for its ability to carry out a wide range of missions with rugged reliability. The first launch of the Geosynchronous Satellite Launch Vehicle (GSLV) nine years ago, using a Russian-made cryogenic upper stage, was, to some extent, the exception. Although the GSAT-1 satellite was put into orbit, a small under-performance of the cryogenic stage meant that it was not the planned orbit. Attempts to move the satellite using its own thrusters were not successful and the satellite was ultimately abandoned.
Despite such a history, the failure of Thursday's GSLV launch with the country's first indigenous cryogenic engine and stage came as a bolt from the blue. The engine and later the full stage have gone through extensive testing on the ground in the course of their development. Moreover, the actual engine that flew on the GSLV was test-fired on the ground for 200 seconds. Exhaustive reviews by experts of the cryogenic stage and the rocket were completed before the GSLV was cleared for launch. After the unsuccessful flight, the ISRO chairman, K. Radhakrishnan, initially suggested that two small cryogenic steering engines, which swivel to maintain the rocket's orientation, might have malfunctioned. Later, however, he indicated that the main cryogenic engine itself might not have ignited. In such a complex system as the cryogenic stage, even a small defect that escapes attention is sufficient to doom the flight. But the space agency would be unwise to confine its analysis to problems encountered with the indigenous cryogenic stage. This is an opportunity for a thorough examination of the entire GSLV rocket and its past five flights. There have, for instance, been problems with the Vikas liquid-propellant engine in previous flights. The procedures for the manufacture, assembly, and pre-flight testing of all liquid propellant engines and stages need particular attention. A comprehensive review would best ensure the future reliability of the GSLV.
