VIDEO-Rescate a lo Indio
Unos aparatos un tanto viejos los Chetak, pero en condiciones diurnas pueden hacer el trabajo.
Aqui en acción durante un rescate reciente.
Rescue operations are under way in India's southern city of Chennai to find five sailors missing from an oil tanker that ran aground in a cyclone.
Coast guard helicopters and boats are combing the sea for sailors from the Pratibha Cauvery.
One of the crew members drowned after a boat carrying him and others capsized near Chennai, in Tamil Nadu state.
Seven people were killed when Cyclone Nilam struck the south-eastern coast with winds of up to 100km/h (60mph).
More than 100,000 people have been evacuated.
The rescue operation had to be suspended overnight because of bad weather, the BBC's Sanjoy Majumder reports from Chennai.
The authorities say they are concerned because the vessel is carrying oil which could create a major problem if it spills out.
Roads and agricultural land across the coast have been badly damaged and power lines have been brought down in several areas by the cyclone struck.
More than 100,000 people were evacuated ahead of the storm and shifted to higher ground, into schools and other temporary shelters.
Many believe the prompt response of the authorities to Cyclone Nilam is one reason why its impact was minimised, our correspondent adds.
Cyclone Nilam hit the Indian states of Tamil Nadu and Andhra Pradesh, and the town of Pondicherry on Wednesday night.
Schools, colleges and cargo operations at the port in Chennai were shut. Fishermen in both states were warned not to venture out to sea.
In December 2011, more than 30 people died and many homes were damaged after a cyclone struck near Pondicherry.
And in May 2010 at least 23 people died as a powerful cyclone caused widespread havoc across Andhra Pradesh.