The Indian Navy, which has pressed a flotilla of vessels, including a submarine, to locate a missing an Indian Air Force transport aircraft, on Sunday said it has sought the satellite imagery of the area from ISRO.
Until Sunday, there was no trace of any debris or signal from the AN-32 transporter which went off the radar on Friday morning over the Bay of Bengal off the Chennai coast, barely half an hour after take-off with 29 people on board.
"A large number ships, helicopters and aircraft are all contributing to the search efforts and the efforts are increasing," Flag Officer Commanding-in-Chief of the Eastern Naval Command Vice Admiral H.C.S. Bisht said on Sunday.
"We are also seeking ISRO's help to get satellite imagery of that area so that we have at least some information... but parallelly we are also reaching out to families," Bisht said.
ISRO or the Indian Space Research Organisation is the space agency of the central government.
Defence Minister Manohar Parrikar, after reviewing the search and rescue operations on Saturday, had asked the commanding officers to keep in touch with families of those on board the missing aircraft.
Bisht said the search has been made difficult by the monsoon weather conditions over the sea.
"The only challenge we are facing is of monsoon condition, rough seas; another challenge is depth which is around 3,500 meters and at some points even more than that," he said.
The cloud base is low and it is raining continuously in the area, he said.
The search continues despite odds and 12 ships are deployed at the time, Bisht said.
"We are continuously searching the area. As of now we have 12 ships, and we will be increasing the assets. We are also doing regular aerial surveillance. The aim is to harness as many resources as possible," he said.
A submarine is also deployed in the area. It will dive on getting some lead, said Bisht.
The aircraft, an upgraded AN-32 belonging to 33 Squadron, took off from Tambaram Air Force Station in Chennai at 8.30 a.m., and was expected to land at Port Blair in the Andaman and Nicobar Islands at 11.30 a.m., officials said, describing it as a "routine sortie".
The recorded transcript of Chennai air traffic radar showed last pickup of the aircraft was 151 nautical miles east of Chennai, when the aircraft was observed to have carried out a left turn with rapid loss of height from 23,000 feet.
The AN-32 is a twin engine turboprop, medium tactical transport aircraft of Russian origin. It can carry a maximum load of around 6.7 tonnes or 39 paratroopers. Its maximum cruise speed is 530 kmph.