It is one of the largest joint global search and rescue efforts in history, involving several countries, multiple aircraft and ships, and the pooling of intelligence.
Yet there is no telling when the first evidence of missing Malaysia Airlines Flight MH370 will surface.
It is almost a month since the plane vanished 50 minutes after departing Kuala Lumpur for Beijing on March 8.
At the height of the search, 26 countries, close to 60 ships and 50 planes were searching 2.24 million square nautical miles - four-fifths the size of the United States - for the Boeing 777-200ER aircraft and the 239 people who were on it.
From satellite firm Inmarsat to the British Air Accidents Investigation Branch and the United States Federal Bureau of Investigation, air crash and other experts have descended on Kuala Lumpur to unravel the mystery.
But apart from a few "credible" leads, the search has yet to uncover any aircraft debris.
Years to find wreckage
Is this another HMAS Sydney in the making? During World War II, people saw the vessel sinking on the horizon off the coast of Western Australia, yet it took 66 years to find the wreckage.
The possibility was raised earlier this week in Perth, now the base for the Australian-led search, which has been narrowed to focus on the southern Indian Ocean.
Air Chief Marshal (retired) Angus Houston, who heads the Joint Agency Coordination Centre in Perth, compared the two incidents when he met journalists on Tuesday.
Even as he noted considerable advancement in technology, he said: "There were eyewitnesses who saw the ship disappear over the horizon but it took us about 60 years to find HMAS Sydney on the bottom of the ocean."
However, Mr Michael Daniel, a retired US Federal Aviation Administration official, told The Straits Times: "I don't think it will take more than 60 years to locate the missing Malaysia Airlines aircraft with the advanced technology that can be employed today."
When Air France Flight AF447 crashed into the Atlantic Ocean in 2009 en route from Rio de Janeiro to Paris, the first signs of debris were located within five days, but it took almost two years to find the black box and most of the wreckage.
The hunt for MH370 could take longer, experts said.
"The search has been vastly complicated by the long delays in searching in the wrong areas," said Assistant Professor Terence Fan, an aviation expert at the Singapore Management University.
"Any debris from the aeroplane would likely have been swept far away from the point of impact in the sea," he added.
The search for MH370 started the day the plane went missing, in the South China Sea where the aircraft is believed to have been flying over when its communication systems were shut down. The search extended to the Strait of Malacca after a review of military radar showed that the plane may have attempted to turn back to Kuala Lumpur.
In a dramatic turn of events a week later, Malaysian Prime Minister Najib Razak acknowledged for the first time that the plane had been deliberately diverted.
Analysis of satellite data revealed that it could have gone as far north as Kazakhstan in Central Asia or southwards towards the Indian Ocean, he added.
Overnight, the search area expanded significantly.