The ‘attacker’ missile veers off path, failing to reach the required altitude

India's efforts to put in place a credible ballistic missile defence (BMD) shield suffered a setback on Monday with the attacker Prithvi missile veering off its path and not reaching its required altitude of 110 km. It reached a height of only 60 to 70 km and spiralled down into the Bay of Bengal. With its failing to come into the “kill zone” of the interceptor missile, no ignition was therefore given for the interceptor to take off from the Wheeler Island, off the Orissa coast.

As per plan, a modified Prithvi missile mimicking an “enemy” ballistic missile's trajectory with a range of 1,500 km., would have lifted off from the launch complex of the Integrated Test Range (ITR) at Balasore in Orissa. A couple of minutes later, an interceptor missile called the Advanced Air Defence (AAD) system, would have lifted off from the Wheeler Island, 60 km. across the sea as the crow flies, from the ITR. The interceptor would have destroyed the incoming “adversarial” missile in midflight, at an altitude of 15 km., in what is called the endo-atmosphere.

Required altitude not reached

But what happened was this: The attacker Prithvi took off from the ITR but did not reach its required altitude and range. It lost its trajectory “So we cannot anticipate the velocity with which it will come down. We did not, therefore, launch the interceptor at all,” explained missile technologists of the Defence Research and Development Organisation (DRDO), which conducted the test.

The interceptor's launch was precluded by “built-in safeguards” in the automated software of the Launch Control Centre on Wheeler Island. “We cannot launch the interceptor for the sake of launching,” they explained. “There is a window. Only when the attacker missile comes within that window, the LCC will launch the interceptor. This is normal inter-lock. You don't waste a missile.”

Scientific Adviser to the Defence Minister and DRDO Director-General V.K. Saraswat told The Hindu that the target missile might have failed to reach its required altitude and velocity due to a malfunction in one of its sub-systems. A committee has been set up to analyse the telemetry data and it would take a couple of days to find out what went wrong.

Fresh test in June

Meanwhile, a new target missile would be realised to conduct the test afresh in June, said Dr. Saraswat.

Since November 2006, the DRDO had successfully conducted three missile intercept tests as part of its efforts to establish a two-tiered BMD shield for protection against incoming enemy missiles. Of the three trials, one was in the endo-atmosphere (below an altitude of 50 km), and two were in the exo-atmosphere (above 50 km).