Just after midnight local time on March 8, 2014, Malaysia Airlines Flight 370 took off from Kuala Lumpur International Airport with 239 people on board settling in for what should have been a routine red-eye to Beijing. The plane never made it to China, instead vanishing somewhere over the Indian Ocean. Its disappearance launched a years-long search, by land and by sea, that was ultimately suspended without any conclusions but that cost millions. To this day, what really happened to Flight 370 remains one of the greatest mysteries in modern aviation.

On Tuesday, more than three years after the tragedy, Malaysia Airlines announced it would be the first airline to begin tracking all of its aircraft with space-based satellites. Doing so will allow the airline to have access to “minute-by-minute, 100% global, flight-tracking data” for all of its planes, according to a joint statement by three companies partnering to provide the service to the air carrier: Aireon, FlightAware and SITAOnAir.

“This is the biggest improvement in flight tracking since radar was invented during World War II,” FlightAware founder and chief executive Daniel Baker said in a video about the technology last fall. “For the first time ever, airlines will be able to track their airplanes even in places that aren’t served by current satellite constellations — and it doesn’t matter if they’re flying over the ocean, if it’s over the desert, if it’s over the North Pole: We’ll know where the plane is.”

Such precise monitoring will be made possible by a network of 66 satellites that Aireon’s parent company, Iridium, plans to launch and have in orbit by the middle of next year. On each of those satellites will be a receiver that can track flights using automatic dependent surveillance-broadcast technology, or ADS-B, a successor to radar. Many aviation agencies around the world, including the Federal Aviation Administration, are transitioning away from radar and using real-time ADS-B for air-traffic control. By 2020, the FAA will require planes to have ADS-B equipment to fly in most controlled airspace.

While it’s unclear whether satellite tracking would have changed anything in the aftermath of Flight 370’s disappearance, the developments come amid new rules for how planes must communicate with air-traffic controllers.

Even though flight disappearances are rare, Aireon chief executive Don Thoma imagines real-time tracking would improve the aviation industry overall by allowing planes to fly more optimal routes, something the FAA noted when moving toward ADS-B technology.

“With ADS-B, pilots for the first time see what controllers see: displays showing other aircraft in the sky. Cockpit displays also pinpoint hazardous weather and terrain, and give pilots important flight information, such as temporary flight restrictions,” the FAA stated on its website. “Relying on satellites instead of ground navigational aids also means aircraft will be able to fly more directly from Point A to B, saving time and money, and reducing fuel burn and emissions.”

Being able to track aircraft entirely through a constellation of satellites in space eliminates coverage gaps even over oceans and remote airspace.

“Real-time global aircraft tracking has long been a goal of the aviation community,” Malaysia Airlines chief operating officer Izham Ismail said in a statement. “We are proud to be the first airline to adopt this solution using space-based ADS-B data.”

That Malaysia Airlines is the first to sign on to this new flight-tracking technology may not come as a surprise. The company suffered the high-profile losses of two Boeing 777 jets — and hundreds of passengers — after a pair of tragedies in 2014.

The first, the infamous disappearance of Flight 370, triggered a multinational search for the wreckage through 46,000 square miles of the Indian Ocean that would wind up costing about $150 million. (It also inspired dozens of rumors and conspiracy theories.) During the search, a few fragments of the plane were found in places as far away as Mauritius and Mozambique. However, the search for the missing jet was officially called off in early 2017, without any conclusive results about where or why the plane crashed.

“Despite every effort using the best science available, cutting-edge technology, as well as modeling and advice from highly skilled professionals who are the best in their field, unfortunately, the search has not been able to locate the aircraft,” the Joint Agency Coordination Center in Australia said in a statement then.

To compound Malaysia Airlines’ problems, the unthinkable struck another one of the company’s jets a few months after Flight 370 vanished. In July 2014, Malaysia Airlines Flight 17, traveling from Amsterdam to Kuala Lumpur, was downed by a missile over eastern Ukraine. All 283 aboard, including dozens of children, were killed in the crash.

Given the questions that continue to surround the disappearance of Flight 370, it is unclear how this technology might have changed the search for the missing plane — or to what degree that tragedy motivated Malaysia Airlines to agree to space-based flight tracking. Aireon’s Thoma noted in the joint statement that “Malaysia Airlines has taken a lead role in the industry since the tragic events of 2014.”

Representatives for Malaysia Airlines did not respond to questions sent by email Wednesday.

“It’s an impossible question,” said Jeff Wise, a science writer and private pilot who took a self-described “detour to Planet MH370” after the jet’s disappearance. “I think the simplest answer would be like we don’t know if it would have helped in that case because we don’t officially know what happened.”

Wise, who also wrote “The Plane That Wasn’t There: Why We Haven’t Found Malaysia Airlines Flight 370,” questioned the utility of technology that would help pinpoint when an aircraft disappeared, which is a rare occurrence.

“This to me kind of feels like a dollar short and a day late,” he said. “The larger question is, is there a big problem with people stealing airplanes? . . . It’s not at all clear that the set of problems that this thing would solve ever occurs.”

Still, the disappearance of Flight 370 and the costly, fruitless search for its wreckage afterward shocked the world’s aviation community into addressing just that. In response to the Malaysia Airlines tragedy, the International Civil Aviation Organization adopted new regulations last year that would require any aircraft in “distress mode” to automatically report its location to flight controllers every minute, among other mandates. The new rules would go into effect by 2021, according to the ICAO.

Thoma, the Aireon chief executive, said the company had been working on space-based flight tracking since well before Flight 370 vanished. However, after the ICAO announced its new mandates, “we kept getting inquiries from companies” about how to comply with real-time tracking, he said.

He said the company has spent about $500 million on building its space-based flight-tracking capabilities. So far, four aviation authorities — from Canada, Ireland, Italy and Denmark — have invested in Aireon.

Thoma acknowledged that minute-by-minutespace-based flight tracking “would not prevent the malicious deactivation of a transponder in flight” but that it could affect how soon flight controllers know about a problem.

At some point on Flight 370, the transponder stopped working (whether it failed or was intentionally shut off by someone remains unknown), resulting in an extended period of time where there was no contact with the aircraft at all. Afterward, investigators could estimate when the plane disappeared only within an imprecise window of time, Thoma added.

“By then, they were looking at hundreds of thousands of square kilometers of search area,” Thoma said. “With our service . . . as soon as that beacon was turned off, we’d know it and you’d know exactly where that occurred. Then you can pinpoint where to begin searching.”

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