The Mystery of Flight 370 Haunts Families and Baffles Experts a Year After Its Disappearance

You can’t blame Jennifer Chong for being a nervous flyer.

Every time she boards a plane, the resident of Melbourne faces the inevitable walk past the cabin’s front row where her husband of more than 20 years, Chong Ling Tan, had been seated on Malaysia Airlines Flight 370.

Twelve months on from arguably the greatest aviation mystery of all time, Chong says those empty seats can still induce panic.

“I start to think that if anything happened, like a hijacking, then he would be the first one who knows because he’s the one nearest to the cockpit,” Chong tells TIME.

Sunday marks one year since MH370 veered off course en route from Kuala Lumpur to Beijing and vanished from radar screens. Planes and ships from seven countries have completed more than 300 sorties over vast tracts of the southern Indian Ocean in search for the errant Boeing 777, but not a single scrap of debris has been recovered.

Now just four boats continue to comb a 23,000-sq.-mi. patch of ocean floor 1,000 miles off the coast of Perth, western Australia. Australian authorities are set to finish trawling the designated search area in May.

During a parliamentary address earlier this week, Australian Prime Minister Tony Abbott acknowledged that officials are beginning to question the value of continuing beyond this point. “I can’t promise that the search will go on at this intensity forever, but we will continue our very best efforts to resolve this mystery and provide some answers,” he said.

But for Chong and hundreds of other distraught relatives, simply giving up translates to abandoning the investigation into how a plane with 239 passengers and crew can simply vanish.

“They’re trying to slowly put the thoughts in the minds of the public and the families, so that they will slowly wind down the search after May because it’s about to money and who’s going to pay,” she says.

Justin Green, a lawyer representing 24 of the victims’ relatives, says the search must continue not just for the families’ sake, but also to improve aviation-safety standards in the future. Green points to the years investigators took to uncover the crucial findings that explained other disasters, such as Air France Flight 447 and TWA 800. “None of the subsequent improvements [to airline safety] would have happened if the countries involved had just given up,” he says.

In late January, Malaysian authorities caught families and aviation experts off guard with a sudden announcement that MH370’s disappearance had been caused by an accident and that no one had survived.

In the absence of facts, myriad theories have surfaced over the past year offering plausible scenarios to explain what transpired. These include that the plane was shot down or driven into the sea by a deranged pilot or passenger. According to experts, no theory can’t be wholly dismissed until concrete evidence proves otherwise.

“With the Malaysian government declaring this an accident, well does that limit or preclude further investigation into these other areas?” asks Mike Daniel, an international aviation-safety consultant based in Singapore. “There’s a difference between an accident investigation as opposed to a criminal investigation.”

Despite talk of halting the investigation or ratcheting down recovery operations, Australian officials remain upbeat that their current search will yield results. “We are cautiously optimistic we’ll find that aircraft,” Martin Dolan, chief commissioner of the Australian Transport Safety Bureau, told the BBC this week. “We know we will find that aircraft if it’s in the priority search area.”

However, experts remain divided over where to look for the plane. Are the four Australian search vessels mapping large swaths of the Indian Ocean’s floor even scanning the correct hemisphere? Some even suggest the plane headed north towards the Caucuses.

“The fact that nothing has been found by the way of debris suggests to me that they’re looking in the wrong place,” said Jason Middleton, an aviation professor at the University of New South Wales in Sydney.

The current search zone was drawn up in accordance with calculations based on a number of electronic handshakes MH370 made with a satellite during its last hours of flight. But Middleton argues that these assessments are problematic at best.

“These calculations rely on a whole bunch of issues that are not easily verifiable by outside sources,” explains Middleton. “The science is not demonstrably repeatable.”

But without a shred of evidence, crucial questions will remain unanswered. Why were the transponders deliberately turned off? Why did whoever had control repeatedly change course? Why was there no Mayday call? And why have Malaysian authorities been reticent to release the flight’s cargo manifest in its entirety?

In lieu of answers, the public clamors for new technology to track planes wherever they might be, yet there’s little evidence that any advances could have prevented this mystery, given that existing systems were deliberately scuttled in the cockpit. (Pilots need to be able to turn off all onboard electronics in case of fire.)

“I don’t know really what to believe. It’s just so bizarre to me,” says Chong. “One year later and I’m in the same position with no further answers.”

As the anniversary approaches, Chong says she plans to brave another flight from Melbourne, where she moved two years ago, to Kuala Lumpur to gather with other families and call for the continuation of the search. Without answers, she tries to remain hopeful that the plane will one day be recovered, but admits that it’s difficult at times to convince herself that her husband and his fellow passengers will be found.

“I’m still hopeful that they will be able to find the plane,” she says. “But we don’t know when. Maybe in one year, 10 years or 40 years. I’ll be holding out hope until then.”