AirAsia QZ8501: Divers in grisly race against time and tide
Leisha Chi reports on civilian divers joining the search
After descending nearly 30m (98ft) into the warm, murky depths of the Java Sea, the faint outline of a plane carcass comes into view.
Tangled wires drift eerily in the current, surrounded by large sections of twisted metal. The diver shines his torch, and vivid red paint appears, followed by large white letters.
It is the tail of the AirAsia plane that crashed last month, killing all 162 people on board.
Flight QZ8501 was travelling from Indonesia's second largest city, Surabaya, to Singapore on 28 December when it ran into bad weather and disappeared from radar.
So far, the tail is the only part of the wreckage to have been found, although on Sunday, sonar scans picked up what could be the fuselage.
That is where Rendra Hertiadhi, a farmer, and nine other civilians from various private sector jobs will be headed.
They are the first team of highly qualified volunteer divers to join the multilateral military operation aimed at finding the plane and recovering the bodies of those onboard.
"We have the ability to dive in tight and overhead environments and in harsh conditions so we want to contribute our skills for this rescue effort," said Mr Hertiadhi.
"We will try to identify parts of the aircraft and then we will try to recover as many bodies as possible."
Rendra Hertiadhi (left) says the divers are trained to operate in difficult conditions
The US, Singapore and Malaysia are among the countries who have contributed ships and equipment to help with the search, which stretches over five zones.
Remotely operated vehicles and sonar are being used to trawl the seafloor for objects. Divers are then sent down to verify and sometimes recover them.
The Java Sea is considered relatively shallow, but the search has been slowed because of bad weather and sea conditions.
Apart from large waves several metres high, divers face strong underwater currents that have reached up to five knots - the equivalent of being carried about an arm's length each second.
Visibility ranges from about one to three metres, but can be much less because of the muddy seafloor.
"We have to work with our hands. We use all our senses. If needs be, we will crawl on the bottom and find things," Mr Hertiadhi said. "We are trained for that. That's why we are here."
Divers have helped identify the tail fin of the missing plane - but the location of other parts is still unknown
Those are not the only challenges they will face. The plane is believed to be upside down and stuck deep in the mud. Many of the passengers may also still be strapped to their seats and getting them out will be tricky.
Divers will have to collect their body parts before putting them in a bag underwater that is then floated to the surface.
Body partsSultan Inamuddin Hospital in Pangkalan Bun is where the recovered remains are first brought by helicopter. They are kept in the morgue's freezers before being transported at the end of the day to Surabaya for identification.
Stacks of temporary coffins, each with a wreath of plastic flowers, line the hospital corridors.
Dozens of staff in white hazmat suits, long yellow rubber gloves and face masks stand around, waiting for what has become an almost daily delivery of corpses. Hospital director Dr Suyuti said it had been a challenge.
"The bodies are worse than before," he said. "Before we had the whole body but now we are just getting the parts of bodies.
"DNA testing will have to be used," he added.
The bodies are being brought to the hospital in Pangkalan Bun
Over in Surabaya, the victims' families continue to wait to give their loved ones a proper burial.
Most of the passengers and crew were Indonesian, but among the victims were Singaporean, British and Korean citizens.
So far, only 48 bodies have been recovered. Just over half of those have been identified.
Indonesian authorities and AirAsia chief executive Tony Fernandes have repeatedly stressed that the main priority is recovering the bodies of those on board.
However, any form of closure still appears to be some way off. The full findings of the air crash investigation will take about a year to be released.
And time is running out if they are to recover all the bodies from the bottom of the sea, putting more pressure on the divers.
Mr Hertiadhi says his team is psychologically prepared for what lies ahead.
"We have been involved in several search and rescue situations where we found similar conditions," he said. But, he adds, this is their first air crash.
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