Snag in PSLV may shorten life of IRS-1D

D Jose in Thiruvananthapuram

It is a small snag, but it could reduce the life of the IRS-1D satellite, which was launched by the Polar Satellite Launch Vehicle C1 on Tuesday.

All went perfectly till the PSLV's fourth stage was activated. There was apparently a leak in the fuel tank which led to the loss of 130 m/sec in the PSLV's speed, according to a senior scientist at the Vikram Sarabhai Space Centre, Thiruvanathapuram. Lacking sufficient power to gain the expected height, the satellite could not reach its pre-determined circular orbit, he said.

The 1,200 kg satellite, set to go into circular orbit at 817 kms, has settled into an elliptical orbit with the maximum distance from earth being 817 kms, the minimum, 300 kms.

While the actual cause for the failure will be known only after closer examination of nearly 500 parameters, scientists who took part in a preliminary analysis said it could be due to a leak in one of the valves. Whatever the problem, the scientists are certain the flaw will affect the longevity of the satellite.

The current orbit will keep sending the satellite through the upper atmosphere causing it to lose speed and eventually burn up due to friction.

A VSSC source said that shifting the satellite from the current elliptional orbit to a circular orbit would mean making use of the 80 kgs of fuel in the satellite reserved for positioning the satellite in orbit. This is more fuel than necessary, the excess being meant to make put the satellite in orbit if something goes wrong. But the extra fuel is not meant to handle such a large deviation, scientists said.

Another scientist at the Indian Space Research Organisation at Bangalore said senior scientists were looking at various ways of salvaging the satellite. He claimed that salvaging the satellite was not a problem considering the experience India has in space technology.

But a pall of gloom still hung over the VSSC. This setback could delay the Geostationary Launch Vehicle programme to be tried later next year, some scientists said. Worse, it may hit India's plan to exploit space technology commercially.

India was hoping to tap the market for launch vehicles by putting into orbit nearly 60 satellites of different countries in the next couple of years. It will take at least one successful PSLV launch to reassure customers now. However, a VSSC source said the current setback may affect the country’s space plans. Several countries have encountered similar problems, he said.

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