Skip to main content

A primer on the latest in the search for Flight 370

By Michael Pearson, CNN
updated 7:27 PM EDT, Tue April 15, 2014
  • NEW: Bluefin-21 may be able to be reprogrammed to go deeper, U.S. Navy official tells CNN
  • Underwater probe back in water in hunt for Flight 370
  • The first effort to deploy a deep-sea probe ended prematurely
  • Surface search efforts are winding down as authorities focus their efforts underwater

(CNN) -- The search for Malaysia Airlines Flight 370 is now in its 40th day, and searchers have yet to turn up a piece of the plane. Here's the latest to catch you up on the search efforts:

What's the latest with the search?

The Bluefin-21 probe being used to search for the missing jetliner in the deep waters of the Indian Ocean returned to duty Tuesday after its first mission ended prematurely. The probe surfaced early in its first deployment after encountering waters that exceeded its current 4,500-meter (14,764-foot) maximum depth. What was supposed to be a 20-hour mission ended in less than eight, according to a source, and found nothing. An official with the U.S. Navy told CNN's "The Lead with Jake Tapper" that engineers believe the Bluefin-21 probe can go as deep as 5,000 meters (16,404 feet) with some software adjustments.

Does that mean something's wrong with the probe?

MH370 co-pilot's cell phone was on
Bluefin-21 'slower than you can walk'
AUV aborted mission, returns early
A policewoman watches a couple whose son was on board the missing Malaysia Airlines Flight 370 cry outside the airline's office building in Beijing after officials refused to meet with them on Wednesday, June 11. The jet has been missing since March 8. A policewoman watches a couple whose son was on board the missing Malaysia Airlines Flight 370 cry outside the airline's office building in Beijing after officials refused to meet with them on Wednesday, June 11. The jet has been missing since March 8.
The search for Malaysia Airlines Flight 370
Photos: The search for Malaysia Airlines Flight 370 Photos: The search for Malaysia Airlines Flight 370

Not at all. In fact, the probe did exactly what it's programmed to do when the ocean floor dips below its maximum depth, said David Gallo, director of special projects at the Woods Hole Oceanographic Institution. "The vehicle's tracking the floor, so when the floor dives, so does the vehicle. And the vehicle goes, 'Uh oh, I'm not supposed to be here' and punches up," he said.

But what if the plane is in deeper waters?

"Well, if the Bluefin cannot bring back the kind of sonographic images they want and the information that they want, then they're going to have to move on to the next level of vehicles with names like Alvin, Remora and the Sea Dragon, and those can go deeper," said CNN aviation consultant Mary Schiavo. "The Sea Dragon can go down to 4.4 miles, or 7,000 meters. And that's the next step that you have to do, is go down to the level in a different kind of vehicle."

Why aren't they listening for pings from the plane's 'black boxes' anymore?

Because the batteries powering the boxes' locator beacons are probably dead, according to the manufacturer and other experts. The batteries were supposed to last at least 30 days, and the plane has now been missing for 39 days. The batteries could have continued powering the beacons for a few more days but almost certainly have run out by now. Searchers using devices to listen for the pings went six days without hearing anything, so they are now focused on the underwater search.

What happens if they find the black boxes?

The flight data recorders, or FDRs, would be transferred to fresh water and then dried before the data they contain would be extracted, Schiavo said. "Then they'll discover on the FDR what they're dealing with and how much of the wreckage they really have to bring up to solve the mystery."

But don't hold your breath. The Flight 370 search is often compared to the hunt for wreckage from Air France Flight 447, which plunged into the South Atlantic Ocean in 2009, killing all 228 people aboard. It took investigators nearly two years to recover the black boxes in that case.

Is the surface search continuing?

Drone sub searches for Flight MH370
Official: MH370 co-pilot's phone was on
Bluefin-21 'slower than you can walk'

It is, but maybe not for much longer. Eleven military aircraft, three private planes and 11 ships participated in the surface search Wednesday about 2,087 kilometers (1,297 miles) northwest of Perth, Australia, according to the country's Joint Agency Coordination Centre. The center's director, retired Air Marshal Angus Houston, said Monday that the surface search is likely to end in the next few days.

Has that search turned up anything?

Searchers found an oil slick in the area over the weekend and are shipping a 2-liter sample back to Australia for analysis. If it's oil typically used in aircraft, the slick could be an important lead. But it may not be. A slick found in the early days of the search for Flight 370 turned out to be fuel oil from a freighter.

Any other new details?

A U.S. official told CNN on Monday that co-pilot Fariq Abdul Hamid's cell phone was on and made contact with a cell tower in Malaysia about the time the plane disappeared from radar.

However, the U.S. official -- who cited information shared by Malaysian investigators -- said there was no evidence Fariq had tried to make a call.

The details do appear to reaffirm suggestions, based on radar and satellite data, that the plane was off course and was probably flying low enough to obtain a signal from a cell tower, the U.S. official said.

READ: MH370: How do underwater sonar subs work?

READ: How do phones work in flight?

INTERACTIVE: The search for Malaysia Airlines Flight 370

Part of complete coverage on
updated 6:11 PM EDT, Thu June 26, 2014
The search for MH370 is moving to an area farther south in the Indian Ocean, said the Australian Deputy Prime Minister.
updated 8:33 PM EDT, Tue June 24, 2014
Erin Burnett speaks to Miles O'Brien about the latest in the search for Malaysia Airlines Flight 370.
updated 12:53 PM EDT, Wed June 18, 2014
Ten experts say that the search for MH370 should move hundreds of miles away from the previous search area.
updated 9:22 AM EDT, Tue June 17, 2014
His wife never came home from her flight on MH370, and now K.S. Narendran is left to imagine the worst of possible truths without knowing.
updated 3:51 PM EDT, Mon June 16, 2014
Families are desperate for results as the search for MH370 reaches a grim milestone. Anna Coren reports from Beijing.
updated 10:55 AM EDT, Mon June 9, 2014
Relatives of passengers are launching an effort to raise $5 million for investigations and a "whistle blower" reward.
updated 3:31 AM EDT, Mon June 9, 2014
Making sure another plane is never "lost" again is the immediate priority for the airline industry.
updated 11:36 AM EDT, Fri May 30, 2014
This handout photo taken on April 7, 2014 and released on April 9, 2014 by Australian Defence shows Maritime Warfare Officer, Sub Lieutenant Ryan Penrose watching HMAS Success as HMAS Perth approaches for a replenishment at sea while searching for missing Malaysia Airlines flight MH370 in the southern Indian Ocean. Two fresh signals have been picked up Australian ship Ocean Shield in the search for missing Malaysian flight MH370, raising hopes that wreckage will be found within days even as black box batteries start to expire.
Was the sound of Malaysian Airlines Flight MH370 striking the water captured by ocean devices used to listen for signs of nuclear blasts?
updated 6:29 PM EDT, Wed May 28, 2014
What was believed to be the best hope of finding the missing plane is now being called a false hope. Rene Marsh explains.
updated 5:05 PM EDT, Wed May 28, 2014
Involved parties, including the manufacturer Boeing, are bracing for a long public relations siege.
updated 7:34 AM EDT, Thu May 29, 2014
Official: The four acoustic pings at the center of the search for Flight 370 are no longer believed to have come from the plane's black boxes.
updated 10:21 AM EDT, Tue May 27, 2014
There is one fundamental question which continues to swirl: Has Inmarsat got its numbers right?
updated 8:13 AM EDT, Tue May 27, 2014
Data from communications between satellites and missing Malaysian Airlines Flight 370 was released
updated 3:42 AM EDT, Tue May 27, 2014
Family members of the people aboard missing plane want independent investigators to review the newly released satellite data.
updated 7:47 AM EDT, Wed May 21, 2014
CNN's Richard Quest explains what kind of information should be contained in the Inmarsat data from Flight MH370.
updated 8:46 PM EDT, Mon May 26, 2014
The underwater search for the missing Malaysia Airlines plane will effectively be put on hold this week, and may not resume until August at the earliest.
updated 9:04 AM EDT, Mon May 19, 2014
Movie-makers in Cannes have announced they're making a thriller based on the disappearance of Malaysian flight MH370.
updated 3:25 PM EDT, Tue May 6, 2014
The search for the missing Boeing 777 has gone on for eight weeks now. CNN's David Molko looks back at this difficult, emotional assignment.