I am in the cockpit of a plane flying at 360kmh just a mere 100m above the southern Indian Ocean. Below is a deep blue expanse, punctuated by the occasional white froth of a wave.
A photographer on the plane - part of the huge Flight MH370 search operation - spots something in the water and captures it with a few rapid-fire clicks. Eagerly, we squint at the thumb-size image on the camera screen.
"Whale," declares New Zealand air force sergeant Sean Donaldson without hesitation.
"How do you know for sure?" I ask.
"You recognise it from the shape," he explains.
I am on board Rescue 795, the call sign for the Royal New Zealand Air Force (RNZAF) P3K2 Orion aircraft taking part in the multinational hunt for MH370.
It is four weeks today since the jet disappeared from civilian radar screens, and an ever-growing number of ships and planes are searching the southern Indian Ocean, where data suggests the plane ended its flight after mysteriously veering off path and running out of fuel.
Australia, New Zealand, the United States, China, South Korea and Malaysia have contributed a range of planes in the search taking place some 1,800km west of Perth.
Orions - four-engine turboprop aircraft - were introduced for anti-submarine warfare in the 1960s and are still used by many countries for maritime patrol.
The aircraft have the range to manage the six-hour transits to and from the search base - Pearce airbase north of Perth - with about three hours to spare for the search itself.
The 13 RNZAF officers on this plane are members of the Auckland-based Number 5 Squadron. They spend most of their time searching for stranded fishermen and boats, or for fishing trawlers with illegal catch in the waters around Polynesia, Melanesia, Micronesia and right down to the South Pole.
These men are trained to spot and differentiate between fishing lines, boat sails, sea life and plane wrecks. But there has been no sign of the last so far.
Aircraft captain Rob Shearer says: "We haven't seen anything that conclusively provides evidence. We haven't seen an airplane seat. We haven't seen a seat cushion. We haven't seen a part of a wing or a part of a fuselage."
Experts reckon that most parts of the plane would have sunk to the seabed or been dispersed by currents by now. But they are hoping - with the help of oceanographic modelling - to locate the wreckage by tracing floating debris back to their origin.
"We are still hopeful that we will find something, because we've got to find something eventually," says navigator Brent Collier. "But it's very hard work."
Rescue 795 has sophisticated equipment, including radar and cameras linked to on-board computers, cylindrical-shaped saltwater-activated smoke buoys, "sonobuoys" with hydrophones that allow crew to detect sound underwater, and global positioning system (GPS) buoys.
The flight I am on has been tasked by the Australian Maritime Safety Authority (Amsa) to comb an area of 20,000 sq km. The team will do so meticulously, poring over the patch of ocean strip by strip, lawnmower-style.
It is an intense, methodical and gruelling process. Sgt Donaldson peers into the sea through a special distortion-free window, ready to photograph any suspicious object.
Tactical coordinator Stephen Graham studies radar readings and real-time images captured by a camera under the nose of the plane. Pilots Shearer and Brett Mckenzie take the Orion up in rapid ascents to scan the ocean with radar as well as make quick descents to allow visual scans.
The camera zooms in on a suspicious item bearing circular shapes on the surface. The chatter on the plane's radio system goes up a notch. The plane banks, circling around for a closer look.
Sergeant Donaldson jumps up from his seat by the window, and quickly removes a smoke buoy from its rack. He shoves the cylinder through a special hatch in the floor, into the sea below. Next, he hauls out the GPS buoy while the plane whirls round again.
A blast of cold air enters the cabin as a colleague pulls open the plane door.
"Now, now, now," someone calls out through the radio system. He hurls the buoy into the water, near the object, so that the search authorities can track its location through GPS.
Later, while scrutinising its photograph, he mutters to Flight Lieutenant Graham: "You know what it looks like to me? Landing gear lights."
The latter replies: "Nah, they won't be able to float." He thinks it is fishing equipment.
No matter. All significant sightings are recorded with their locations and reported back to Amsa.
Sgt Donaldson turns to me. "Until you get a warship to figure it out, you can't say definitely what it is," he says.
Ships are involved in the search to retrieve flotsam that may be linked to MH370 for analysis. But the marker buoys do not always work. Flight
Lieutenant Collier concedes: "The buoy may drift differently from the objects in the water. They may drift very slowly and the buoy may drift very fast. When the ships go and pick up the marker buoy, the object might not be close to it any more."
Conspiracy theories have been brewing about what actually happened to MH370 but the crew does not dwell on them. The men simply want to do their job, hopefully find wreckage and bring closure to the families of the 239 people on board the flight.
Malaysia Airlines has announced that everyone on board the flight is presumed dead, turning what was initially a search and rescue operation into a search and recovery operation. But anguished relatives remain sceptical without physical evidence of a crash.
The long operational hours are proving a challenge for the New Zealand air crew. As they are not allowed to fly for more than 150 hours in a month to prevent fatigue, they will hit the limit in about two weeks, and need to be replaced by other members of their squadron.
And this is a search that could carry on for years. Data shows that Flight MH370 had its communications systems manually turned off before it veered drastically off its original course from Kuala Lumpur to Beijing, travelling for hours down south to the Indian Ocean on March 8.
In 2009, Air France Flight 447 from Rio de Janeiro to Paris plunged into the Atlantic Ocean under less mysterious circumstances but, even then, it took two years to retrieve its flight data recorder.
On board Rescue 795, the crew is conscious of the need to avoid using up all their flying hours.
Flight Lieutenant Graham says: "If there is an emergency in this area now where there are people in the water and we need to respond right now, we need to have people in the aircraft available for that."
The search for MH370 remains "very important", he says, adding matter-of-factly, "but if we drop out of this for a day, nobody will die".
This article was published on April 5 in The Straits Times.
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