In search for Malaysia Airlines Flight 370, two new signals buoy hope

Two new, fainter signals detected
Two new, fainter signals detected


    Two new, fainter signals detected


Two new, fainter signals detected 01:27

Story highlights

  • Thursday's search area is scaled back to cover about 22,400 square miles
  • Four signals total are detected in the same general area
  • Previous signals are "consistent" with that of a flight data recorder
  • The signals are getting weaker

In a sea of uncertainty, two bits of good news emerged Wednesday.

Searchers picked up fresh signals that officials hope came from locator beacons attached to the so-called black boxes in the tail of Malaysia Airlines Flight 370, which disappeared more than a month ago while carrying 239 people from Kuala Lumpur to Beijing.

The Australian ship Ocean Shield first picked up two sets of underwater pulses Saturday. It heard nothing more until Tuesday, when it reacquired the signals twice. The four signals were within 17 miles of one another.

"I believe we are searching in the right area, but we need to visually identify wreckage before we can confirm with certainty that this is the final resting place of MH370," said retired Air Chief Marshal Angus Houston, who's coordinating the Australian operation.

The second piece of good news? Authorities analyzed the signals picked up over the weekend and concluded that they probably came from specific electronic equipment rather than from marine life, which can make similar sounds.

Could the pings be from MH370?
Could the pings be from MH370?


    Could the pings be from MH370?


Could the pings be from MH370? 02:07
Hear possible 'ping' detected in search
Hear possible 'ping' detected in search


    Hear possible 'ping' detected in search


Hear possible 'ping' detected in search 00:40

"They believe the signals to be consistent with the specification and description of a flight data recorder," Houston said. "I'm now optimistic that we will find the aircraft or what's left of the aircraft in the not too distant future."

How to hunt for pings

Signals getting weaker

Thursday is Day 34 in the search for Flight 370, which went missing March 8. Authorities are pinning their hopes of finding it on the pings.

Time is of the essence: The batteries powering the flight recorders' locator beacons are certified to emit high-pitched signals for 30 days after they get wet.

"The signals are getting weaker," Houston said, "which means we're either moving away from the search area or the pinger batteries are dying."

• The first signal, at 4:45 p.m. Perth time on Saturday, lasted two hours and 20 minutes, he said;

• the second, at 9:27 p.m. Saturday, lasted 13 minutes;

• the third signal was picked up Tuesday at 4:27 p.m. and lasted five minutes and 32 seconds;

• the fourth, at 10:17 p.m. Tuesday, was seven minutes long.

"It's certainly encouraging that more signals have been detected," Pentagon spokesman Adm. John Kirby told CNN. "There is still much work to do, however."

Four reasons to believe; six reasons to doubt

Scouring the ocean for debris

Though plenty of debris has been found, none of it has been linked to the plane, and so the search goes on.

Thursday's effort is set to include up to 10 military planes, four civil aircraft and 13 ships.

Three of them -- the Ocean Shield to the north, and the British HMS Echo and Chinese Haixun 01 to the south -- were focusing underwater.

All told, everyone involved will be scouring a 22,400-square-mile (58,000-square-kilometer) zone centered about 1,400 miles northwest of Perth.

What you need to know about a black box
What you need to know about a black box


    What you need to know about a black box


What you need to know about a black box 01:51
Up to 14 planes in search for Flight 370
Up to 14 planes in search for Flight 370


    Up to 14 planes in search for Flight 370


Up to 14 planes in search for Flight 370 02:42
Hiding in another plane's shadow?
Hiding in another plane's shadow?


    Hiding in another plane's shadow?


Hiding in another plane's shadow? 03:57

That's roughly the size of West Virginia.

But Thursday's search area is about three quarters of the size of the area teams combed the day before and far smaller than what it was a few weeks ago.

"I think we have got a much clearer picture around the areas that we need to concentrate on," Kevin McEvoy, a New Zealand air force commodore involved in the effort, told CNN's Erin Burnett from Auckland.

Authorities reduced that area after analyzing satellite data and concluding that Flight 370 set off from Kuala Lumpur, Malaysia, toward Beijing, turned back over the Malay Peninsula, then ended up in the southern Indian Ocean.

Why? The answer may reside in the information stored inside the cockpit voice recorder and the flight data recorder.

More pings raise more questions

The ocean to contend with

Hopes were initially raised when a Chinese ship detected pulses last Friday and Saturday that may have been from the plane.

According to McEvoy, "the main focus" now centers on the site of Ocean Shield's discovery. The ship used more advanced detection gear than that aboard the Chinese vessel, whose find was about 375 miles away, leading Houston to believe they are separate signals.

Beyond the dwindling battery life, the ocean also presents challenges: The Ocean Shield signals were in water about 2.6 miles deep, meaning any number of things could literally impede or otherwise disrupt the pulses.

To limit further roiling of the waters, officials are limiting sea traffic in the area. That's one reason that there's no rush to put drones in the water to take photos.

Another reason: Drones are painfully slow. The Ocean Shield towing a pinger locator can search six times the area than can a drone equipped with sonar, Houston said.

"The better the Ocean Shield can define the area, the easier it will be for the autonomous underwater vehicle to subsequently search for aircraft wreckage," he said.

What happens after the Malaysian plane's pingers die?

A painstaking process

The more pulses investigators detect, the more they will be able to zero in on the locator beacons, which emit signals for 5 miles in all directions, said Mary Schiavo, a former inspector general for the U.S. Department of Transportation.

Once they lose the signals, authorities will start the painstaking process of using side-scanning sonar to search the ocean floor.

Next steps in underwater search

Somewhat 'befuddling'

The absence of wreckage near the detected signals leaves some skeptical, worried that the Chinese and Australian ships' finds could mean more false leads in an investigation that's been full of them.

Acknowledging "a very high-speed vertical impact" could explain the lack of aircraft debris, CNN aviation analyst Miles O'Brien said. He said there's reason to be cautious.

"It's either the most extraordinary event, or those pings weren't real," he said. "It's somewhat befuddling."

In Beijing on a 10-day trip to the Asia-Pacific region, U.S. Defense Secretary Chuck Hagel appeared to be hopeful but restrained. "There has been some new evidence here that maybe these new and emerging sounds may lead to something, but it's important we don't lift anyone's hopes -- the families of these passengers -- in an unfair way," he told CNN's Jim Sciutto in an exclusive interview.

Sarah Bajc, the partner of American passenger Philip Wood, told Burnett that she isn't sure about anything.

"All of us pretty well agree that, until there's the bulk of the plane, the bulk of the bodies discovered, and a black box intact, we won't believe that it's final evidence," Bajc said Wednesday from Beijing. "I don't think the authorities have given us much confidence of their investigative skills so far."

The lack of clarity makes it hard to "grieve properly and ... move on," she said.

"I want to fight to find him, in whatever form that ends up being," said Bajc, who is coordinating with other passengers' kin to press for answers. "And I think most of the families feel the same way."

Until he gets answers, Steve Wang, whose mother was on the plane, is clinging to hope while trying to hold himself together. "We're just going through so many kinds of emotion," he said of his position and those of other relatives of passengers. "Desperate, sad and helpless -- something like that. Everything."

How deep is deep? Imagining the MH370 search underwater

The hunt for a Flight 370 ping: How they are doing it

Timeline: Leads in the hunt for Flight 370 weave drama

      Malaysia Airlines Flight 370

    • nr intv moni basu husbands quiet suffering flight 370_00020822.jpg

      An empty space on earth

      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.
    • 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.

      Is this the sound of the crash?

      Was the sound of Malaysian Airlines Flight MH370 striking the water captured by ocean devices used to listen for signs of nuclear blasts?
    •  A crew member of a Royal New Zealand Airforce (RNZAF) P-3K2-Orion aircraft helps to look for objects during the search for missing Malaysia Airlines flight MH370 in flight over the Indian Ocean on April 13, 2014 off the coast of Perth, Australia. S

      Search back to square one

      What was believed to be the best hope of finding the missing plane is now being called a false hope. Rene Marsh explains.
    • Caption:A Chinese relative of passengers on the missing Malaysia Airlines flight MH370 uses a lighter as she prays at the Metro Park Hotel in Beijing on April 8, 2014. The hunt for physical evidence that the Malaysia Airlines jet crashed in the Indian Ocean more than three weeks ago has turned up nothing, despite a massive operation involving seven countries and repeated sightings of suspected debris. AFP PHOTO/WANG ZHAO (Photo credit should read WANG ZHAO/AFP/Getty Images)

      Bring in the lawyers

      Involved parties, including the manufacturer Boeing, are bracing for a long public relations siege.
    • The painstaking search for Malaysia Airlines Flight 370 got a vote of confidence Friday that the effort is headed in the right direction, but officials noted that much work remains.
Credit: 	CNN

      Pings likely not from Flight 370

      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.
    • INDIAN OCEAN (April 14, 2014) -- Operators aboard ADF Ocean Shield move U.S. Navy's Bluefin-21 into position for deployment, April 14. Using side scan sonar, the Bluefin will descend to a depth of between 4,000 and 4,500 meters, approximately 35 meters above the ocean floor. It will spend up to 16 hours at this depth collecting data, before potentially moving to other likely search areas. Joint Task Force 658 is currently supporting Operation Southern Indian Ocean, searching for the missing Malaysia Airlines Flight 370. (U.S. Navy video by Mass Communication Specialist 1st Class Peter D. Blair/RELEASED)

      Underwater search on hold

      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.
    • Movie-makers say they have recruited leading Hollywood technicians to bring their experience to mid-air flight sequences.

      An MH370 movie already?

      Movie-makers in Cannes have announced they're making a thriller based on the disappearance of Malaysian flight MH370.
    • The story of the search

      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.