Malaysian Airlines Flight MH370, carrying 227 passengers and 12 crew members, was on its way to Beijing when it disappeared on March 8, 2014. Within two or so hours after taking off, all communications from the place were lost, the plane’s transponder stopped emitting signals, and the plane vanished from all radars and satellites. The disappearance of MH370 has become one of the biggest mysteries in aviation history and the search for it, the biggest and most expensive ever. 

The search was suspended formally in January 2017. However, for the families, relatives and friends of those on board, it has not stopped even for a single day.

Jiang Hui’s mother, who was 71 years old when MH370 disappeared, was on the flight from Kuala Lumpur. He and his family have never given up hope. 

“We have organized relatives of the passengers from Malaysia, Australia and so on to visit authorities and hold memorials and rallies in Malaysia and Australia," Jiang said. "There are passengers from 14 countries on MH370. It's an international effort.”  

The search has never been easy. When pieces of debris washed up on the beaches of Reunion, Jiang and other relatives of passengers went to the Indian Ocean island in search of more evidence but met many obstacles.

 “The villagers didn’t know much about the plane, and the language barrier was there," he said. "We had a translator to translate our Chinese to English, another translator from English to French, and yet another, from French to local language.” 

Now a year after the search was suspended, the US oceanic exploration company Ocean Infinity was setting out on Wednesday. The new search attempt tries to reach the newly defined 25,000 square kilometers. 

Ocean Infinity seems quite determined to find the missing plane: It's new 90-day contract is on a “no cure, no pay” basis. That is, the company will not receive any payment from Malaysian government if the plane is not found. If successful, Ocean Infinity will receive up to 70 million US dollars in payment.

With the company's commitment and new technology available today, Jiang is “carefully optimistic,” and thinks the search should continue even if the company fails. 

“Crews from Ocean Infinity are brave people and I am truly grateful and wish them all the luck," he said. "But MH370 is too mysterious and the Indian Ocean is too big. If Ocean Infinity fails, I hope the Malaysian government can use the $70 million to establish a bounty and create a long-term searching system, so that other companies may also participate in the search in the future.”   

Jiang stresses that what truly matters to them is to know where their families and loved ones are. 

"If we are to find MH370 and its passengers, through this search or any search in the future, I only want to know where the passengers are and what happened to them. (As) Simple as that." 

The search may or may not yield any results. What the families of those on board are desperately looking for, after four years in the dark, is a definitive closure.