New Delhi, April 13: India’s defence scientists today claimed that the “successful” test firing of the Agni III was a step towards developing longer range missiles with inter-continental capability.

The Agni III missile validated a number of new technologies — including “a warhead detonation system”, a euphemism for a nuclear payload — for the first time. Some of these technologies will allow India to extend the range of future missiles such as the Surya that is on the drawing board to beyond 5,000 km.

A submarine-launched variant of the Agni III missile is also on the Defence Research and Development Organisation’s agenda.

“We’ve designed Agni III as a stepping stone for many future projects with capabilities of much longer range,” said M. Natarajan, DRDO chief and scientific advisor to the defence minister. “A longer range missile will take minimum three years (to develop).”

The Agni III, launched from Wheeler’s island off the Orissa coast, flew nearly its full range of 3,000 km in about 13 minutes, climbing to an altitude of 365 km, before re-entering the atmosphere at 15 times the speed of sound, and impacting beyond the equator.

The missile, carrying a payload (warhead) of 1.5 tonnes fell into international waters that are not territorial.

Avinash Chander, the mission director and head of DRDO’s Advanced Systems Laboratory, Hyderabad, said the final data from naval ships tracking its flight is yet to be analysed. The missile impacted its designated target, he said, “within a few hundreds of metres”.

Chander did not say exactly how far the Agni III flew, but said the missile was designed to impact a target within a range of 3,000 km, and it hit within a kilometre of the target.

This was the second test of the Agni III after one on July 9 last year failed. Chander explained that the failure was triggered by a defective heat shield that allowed hot jet exhaust from outside to penetrate the missile and burn insulation off two wires, causing loss of control. Agni III-01 had plunged into the Bay of Bengal after only 65 seconds of normal flight.

At least 258 industries in the public and private sector were involved in the production of key components of the Agni III.

Natarajan said it could take two to three more tests to certify the missile as fit for induction into the services.