Buffeted by two consecutive failures of the Geosynchronous Satellite Launch Vehicle (GSLV) and the scandal that erupted over a deal to provide S-band spectrum to a private company, the Indian Space Research Organisation has been yearning for some good news to lift the morale of its scientists and engineers. It got that on Wednesday when the workhorse of India's launch vehicle programme, the Polar Satellite Launch Vehicle (PSLV), turned in another flawless performance. Well aware that it could ill-afford another launch failure, and that too of the PSLV with its impeccable record, the space agency had gone to great lengths to ensure a successful flight. The launch, originally scheduled for earlier this year, was postponed for checks on the Vikas liquid propellant engine. Lifting off from the Satish Dhawan Space Centre at Sriharikota on its 18th flight, the rocket precisely followed the planned trajectory and delivered three satellites into orbit 18 minutes later. The main payload, the earth-viewing Resourcesat-2, will provide data for a multitude of practical applications ranging from agricultural monitoring to studying snow cover and coastal zone mapping. India launched its first remote sensing satellite, the IRS-1A, aboard a Russian rocket in 1988. Many more followed, especially after the PSLV became available. India now has one of the largest constellations of remote sensing satellites in operation, supplying data to users at home and across the globe.
The PSLV was conceived as a rocket that would put 1,000-kg remote sensing satellites into orbit. After the failure of its first flight in 1993, the rocket was successfully flown a year later and has not looked back since. In the course of 17 successful launches, it has put 47 satellites into orbit, 21 of them Indian. Through a variety of weight-reducing measures and increased propellant loading, the rocket's performance has been steadily enhanced. In Wednesday's flight, the PSLV effortlessly carried three satellites that together weighed over 1,400 kg. The rocket has also proved capable of carrying out a range of missions. Apart from launching remote sensing satellites into polar orbit, it put the Kalpana meteorological satellite into a near-equatorial orbit and took the Chandrayaan-1 spacecraft on the first leg of its journey to the Moon. Three more launches of the PSLV are scheduled this year. ISRO chairman K. Radhakrishnan has promised that a launch of the GSLV will follow. Indeed, a key challenge for the space agency will be to transform trouble-prone GSLV, equipped with an indigenous cryogenic stage, into as reliable a rocket as its predecessor.