your insurance rates. if you want to save hundreds, talk to farmers. ♪ we are farmers bum - pa - dum, bum - bum - bum - bum ♪ [announcer] the more you know, the more you could save. farmers could help you save hundreds on your auto insurance. call your local agent or 1-800-470-8496 today. happening now, a "situation room" special report on the mystery of flight 370. new beacons of hope. ships hear electronic binges deep below the sea. now they're scrambling to find them again. a new zealand air force commander joins us with a live update this hour. we also have new details about the flight path and a possible move to avoid radar. is it an important clue about what happened? we're digging deeper into the claims and counterclaims. plus, grief and doubt. some passengers' relatives simply can't or won't believe that the newest lead might pan out. we want to welcome our viewers in the united states and

around the world. i'm wolf blitzer and you're in the "situation room." this is cnn breaking news. >> right now, crews are working around the clock to investigate underwater signals that just may, repeat, may have come from flight 370. the united states navy says it's cautiously optimistic the signals heard hours ago could be from the jet's two black boxes. a month after the plane vanished, the batteries of those flight recorders may die in any moment if they're not dead already. that's only adding to the urgency as high-tech devices comb the sea and planes get ready right now to return to the search area. they're all looking for some definitive proof that the missing airliner crashed. our correspondents are in the field, covering all the breaking developments. we have our own team of experts in the "situation room." aviation correspondent renee marsh for the very latest. >> wolf, it's down to the wire for these crews. we're now two days past the

required shelf life of these batteries. there's no guarantee how much longer they will last if they haven't died already. but tonight, authorities are cautiously optimistic. there's still no wreckage, but there was a distinct sound coming from under water, and as we speak, they are trying to determine if it's flight 370's black boxes. they haven't been able to recapture that sound just yet. it's the sound search teams have desperately been trying to find. and now they just may have. the pinger locator towed behind the ocean shield detected distink sounds over the weekend that may be from the black boxes. >> the first detection was held for approximately 2 hours and 20 minutes. the ship then lost contact. the second detection on the return leg was held for approximately 13 minutes. >> reporter: the detections about a mile apart in water more

than 14,000 feet deep. on one occasion, two separate pings were heard which only heightened the excitement because the cockpit voice recorder and the flight data recorder ping separately. >> this is a most promising lead. >> reporter: but we've heard that before. >> the most promising leads -- >> credible leaves. >> reporter: but this time it could be different. >> the audible signal sounds to me just like an emergency locator beacon. >> reporter: search crews are cautiously optimistic. >> certainly, you know, we're jumping to conclusions here. we definitely need to reacquire the signal to confirm it is the aircraft. >> reporter: the task now, the ocean shield is trying to find the signal again and hoping for confirmation. if the ping is detected again, crews will launch this underwater drone. it can scan the ocean floor and take photos of any potential debris. at the same time, 375 miles away, chinese ship and the

british hms echo are trying to confirm pings the chinese briefly detected friday and saturday. australian officials say it's unlikely to be from the same source. >> it's quite possible for sound to travel great distances, but be very difficult to hear near the surface of the ocean, for instance. >> reporter: all of the activity is happening right along this ark. where a partial satellite connection placed the plane at 8:19 a.m. the day it disappeared. the australians believe it's the most likely place the plane went do down. also emerging, new details about the plane's flight path. an official tells cnn after it makes that left turn, based on radar data, it skirts indonesia, which you're seeing there. that just suggests or raises the question, was the person in the cockpit trying to avoid radar? we may be one step closer to finding out if the new signals detected are truly from the black boxes, but you just had

the navy commander on our air and they still haven't been able to recapture that sound as yet. >> maybe a result of the batteries having died in the interval or haven't gotten close enough because there's a limited amount of opportunity. the weaker the batteries, the weaker the signal it's emitting. rene, stand by. i want go to do the base of operations for the search. matthew chance is in perth, australia. they're getting ready to take off, planes over there, to resume the aerial search. on the sea the ships have been working 24/7, right? >> reporter: yeah. there's been no letup, wolf, in this search operation. now with this subsurface search under way. of course, they can carry on even when it's dark. carry on 24 hours. so that's been continuing through the night. you're right, they haven't managed to relocate those signals that were emitted and that they recorded over the weekend. but even if they don't find them again, i think it's important to remember that it will have narrowed significantly the

search area down from that fast tracts of indian ocean to a much smaller three mile square box. so it's a positive development that they even detected these signals in the first place. but you're right, in the next hour or so, we're expecting the observation flights, a dozen or so military and civilian planes taking off mainly from this air base outside of perth because they haven't let up in looking in other areas of the search zone as well. they're still kind of looking for debris on the surface of the ocean, and so that will continue. that aspect of the search will continue. even as the focus remains this ocean shield and them trying to sort of relocate that pinger that they detected earlierer. wolf? >> you're talking to officials over there in perth, matthew. take us a little behind the scenes. are they giving you an upbeat assessment privately that they think they've located these two black boxes? are they very, very cautious ? what kind of sense are you getting from your private conversations with these folks?

>> reporter: well, i think, you know, angus houston, the australian air chief marshal that's heading up this multinational effort, he's a very measured character. you know, he doesn't say things that he feels he may have to retract in a few days' time or few weeks' time. there's been a shift in the level of clarity since he started doing those press conferences. so he said he's much more optimistic this week, yesterday, than he was last week. and i don't think he'd be saying that if he didn't have a pretty good indication that what they located -- remember, they were listening to those regular second interval pings for more than two hours. 2 hours, 20 minutes on one occasion. i think he wouldn't be saying he was optimistic unless they were pretty confident this was going to come to thing. so, yeah, i think there's a lot more confidence. they're much more upbeat. they haven't located the plane yet. they're keen to emphasize that. they appear to be on the right track. >> u.s. navy similarly saying it's cautiously optimistic that

they may have located those two black boxes. matthew, thank you. american military, proving to be crucial for the underwater search for the plane. let's go to our pentagon correspondent barbara starr. how confident is the navy this, in fact, could be pingers coming from those two black boxes? >> well, wolf, as we have been saying, optimistic, encouraged, but nothing definitive yet. crucially, that's what the technology must demonstrate. something definitive. what we are talking about, wolf, and we've shown pictures of it for several days now. this pinger locator device you see in the water, think of it this way. it's like mowing grass. it's going to go back and forth. back and forth. until it can begin to narrow down the area where it is hearing the sound. that is what's going to get it down to that, what matt withdrew w you was talking about, that three mile by three mile box. once they can do that, once they get that pinger sound isolated into a much more narrow area,

then the second piece of technology goes to work and that's that underwater submersible device with its side scan sonar. that will go in the water, go down and try and get further information, acoustic signatures, knphotos, whatever can from the data recorder and voice recorder that they believe hopefully are on the sea floor there. but until they can narrow that area down, this technology isn't really designed for a wide area search so it doesn't do them as much good as you might think. >> barbara, did the u.s. navy play a specific role in where to deploy the towed pinger locator? in other words, how much of a say did the u.s. play in that situation? >> well, you know, wolf, when you talk to folks involved in this, they will tell you this is now a very collaborative effort between australia, which is in the lead, malaysia, the united states, other nations that are devoting their assets to it. this is where the data has taken them. the australians say everything

they have shows this is the most likely spot where the plane went down. the early days of, perhaps, not a lot of cooperation from the malaysians seems to have faded. everybody, they say, working together very well now. and one indication is there is discussion behind the scenes that they may have to send a supply ship to this area. that if this is really what it turns out to be, there will be an operation at sea for some time to come. a supply ship may have to move in. so all of these other ships can stay on station and do their work around the clock, wolf. >> all right. barbara, thanks very much. good information, barbara starr at the pentagon. let's bring in our panel. our aviation correspondent rene marsh is here with us along with our aviation analyst miles o'brien and peter. our law enforcement analyst tom fuentes. peter, let's say they put that bluef bluefin-21 down there, the sonar to detect wreckage from the

plane. how long presumably would that take if, in fact, those pings were coming from those two black boxes? >> well, if they had the pings narrowed down and they had them zeroed in, it could take a few days or couple of weeks. if they're not able to reacquire the pings, it's going to take a very long time. >> when you say long time, miles, could take weeks if not months. a lot of us remember the air france plane. they found wreckage within five days and took them two years to find the black box. >> they search one season, had to wait for the winter. came back the next season then finally made the find. this is, as some have been describing it, a little like watching paint dry as this process unfolds. the only way to do it is do it sl slowly. remember where it is, 15,000 feet of water. it's pitch dark, it's cold. there's all kinds of issues that work against them as they do this work. >> all of us are a little bit more upbeat now that they may have located the plane because

the plane presumably would not be far away from the two bloack boxes if in fact the two hours of pinging the u.s. navy says it detected were coming from the one black box, another 15 minutes from the second, that's a very encouraging development. >> right. that's what they're saying, wolf, marine life and seismic events could not have lasted that long, that precisely at that frequency. that's what they're basing their optimism on right now. >> the chinese detection of pings the day before, most experts i take it, rene, are sort of discounting that. one lasted only 90 seconds. one lasted a few seconds. it was not considered all that credible. >> you know, when you listen to the press conference that angus houston gave, he really only talked about the pinging that the australian ship, ocean shield, picked up. and he called that their most promising lead speaking about what they picked up. the reason why more attention is being paid to ocean shield and what they detected is because they're using that very sophisticated equipment. the towed pinger locator.

very, very high-tech equipment here. and also, we can't discount the fact that they heard this sound for a two-hour block. that's a long period of time. what the chinese were talking about, 90 seconds. the manufacturer, himself, said if this pinger is working, it's continuously pinging. it's not going to ping for two seconds and then stop. so that's probably why they're weighing more heavily on what the ocean shield is. >> the chinese detection capabilities were minuscule compared to what the u.s. has out there. >> yeah, they were designed for shallow water work. they were only good for a few thousand feet. attached to the end of a pole in a, you know, ad hoc manner. it was not a serious detection. >> at least 300 miles or so away from where the u.s. navy detected those pinging signals coming in for about two hours. i want to play a clip, this is the u.s. navy commander william marks. i spoke with him in the past hour. listen to this. >> we are working around the

clock to reacquire the signal, but there were some encouraging developments over the weekend. we are cautiously optimistic. probably more so just when it happened. and as the weekend goes on, we're still working hard to get it back. this is a 24-hour operation. we haven't quit since we've initially heard these signals. we've been going continuously around the clock and we haven't been able to reacquire them. >> william marks, commander of the u.s. navy commander speaking with me in the last hour. let's get a live update now on this search. once again, it try to reconnect, find it, listen to those pings. the new zealand air force wing commander andy scott is joining us via skype. commander, thanks very much for joining us. what's the very latest information you're getting? new zealand is part of this multinational force. do you think you've actually found this plane based on the pings coming from those two

black boxes? >> good afternoon, wolf. at the end of the day, what we're looking at now is a new dimension that the search is going into, so it doesn't fundamentally change the job we have for the fixed-wing aircraft that are participating in the search in that we still need to try to locate the debris which will help refine that search area for the black boxes even more. as you have heard in the bulletin earlier, no doubt, the amount of ocean that the vessels can actually cover with the detecters, it's at a very slow speed, and so they still need to try and refine that area down even more. and so what we're now seeing with those search aircraft is although it's still primarily a visual search with a bit of radar there to go and help pim up larger objects as well, it's actually just still looking at all of those individual leads, whether it's from the chinese vessel, whether it's from ocean shield, and there are multiple search areas every day now. >> do you believe that two hours

of pinging that the u.s. navy detected thanks to the towed pi pinger locator, another not very far away, do you think, in fact, those pings were coming from the two black boxes? >> it's the most encouraging evidence that we've had to date. now, of course, there's been highs and lows throughout the search, and it is part in parcel of this sort of activity. unfortunately. but certainly it is very, very promising news that we're hearing at the moment. >> the fact that you haven't been able to recreate that pinging capability, some are suggesting it's because maybe the batteries are so weak or they've actually died and because the 30 days are up. what's your assessment? >> so, the batteries, themselves, they just start to lose power. so it doesn't necessarily mean that it stops. it's not a switch that turns off. it's just the signal strength isn't going to be quite as strong. but what you're actually seeing at the moment is with the detections that are being made

under water, there's a large propagation that that signal can effectively be heard. the equipment that's being used is very, very sensitive. it is picking up all manner of noises underneath the ocean. whether that's marine life, and, of course, in this particular case, a steady signal coming from something. but ultimately, it's going to be hard to reacquire again because changes in water density, storms, they can all effect how that signal propagates. >> i take it, though, commander, you're much more upbeat about the u.s. detected pings as opposed to what the chinese detected about 300 miles away. >> well, all of those leads with still being followed, so yesterday, for example, a new zealand aircraft was searching in an area based off those chinese detections, so those signals can carry so far under water, literally we're talking hundreds of kilometers basically, that we still need to go and explore every avenue. so, yeah, as i said yesterday,

new zealand was going looking in the area of the chinese detections. >> wing commander royal new zealand air force. commander, thanks very much for joining us. >> you're welcome. still ahead, flight 370 families mark one month since their loved ones vanished along with the plane. they'll wonder if they'll ever have closure. we're going to show you the kinds of equipment now being used to find those two black boxes. are some more reliable than others? ahhh. beautiful day in baltimore where most people probably know that geico could save them money on car insurance, right? you see the thing is geico, well, could help them save on boat insurance too. hey! okay...i'm ready to come in now. hello? i'm trying my best. seriously, i'm...i'm serious. request to come ashore. geico. saving people money on more than just car insurance.

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"crossfire" won't be seen tonight so we can bring you more of our special report on the search for flight 370. we're following the breaking news about malaysia airlines flight 370. u.s. navy now saying it's, quote

cautiously optimistic, signals picked up in the search area are, in fact, pings from the plane's two black boxes. meanwhile, families of the passengers are marking an emotional milestone. the mystery is now one month old. cnn's david mckenzie is joining us from beijing with more. david, tell us about the vigil that's being held there in the chinese capital. >> reporter: well, wolf, this vigil has been going on for hours now. they're effectively retracing the moments that this flight vanished, when it was due to be here in beijing, and these family members have been stuck in this hotel behind me for many, many days now. and it was a time for them to reflect with all of these emotions that have been going through them for all of these days. as they wait to get word, confirmation what happened to their loved ones. >> 31 days without knowing.

the trauma for families of the missing is raw. and unending. >> for the family members, it's been a harrowing month of waiting and wondering what happened to their loved ones that vanished on flight 370. and tonight they're trying to pray and commemorate to get some kind of closure. >> we're just going so many, so many kinds of emotion. maybe just desperate, sad, and something like that. everything. >> reporter: they're marking the milestone with a nightlong vigil. retracing every detail they do know about the flight and the enormous effort to find it. but after weeks stuck in this hotel waiting, it's just too much to bear for some. do you think people are starting the grieving process yet?

>> oh, my. >> no, not yet. until something was found, if anything was soon found, we would never give up. >> reporter: never give up hope? >> yes. right. we know that with the time passing, the hope, less hope, but we will still have hope. >> reporter: even if that hope runs out, they want to keep the spirit and the memories alive of the 239 souls aboard flight 370. well, wolf, so much of the focus has been on the search area this plane. on any debris that might be found, on the pinger locations. all of this is obviously fascinating and important, but this is ultimately a human story with very real consequences for very real people. and with more than 150 onboard from here in china, the chinese

families are certainly bearing the brunt of that not knowing and that at this stage i think is what they really want. so they can move on with their lives. wolf? >> what a heartbreaking story it is. now in week five. david mckenzie in beijing. thank you. let's bring in cnn's tom foreman right now, he's got a closer look at those underwater pings that have the u.s. navy saying they're cautiously optimistic. walk us through a little bit, tom, right now the kind of search equipment that's being used. >> you know, wolf, the differences between the teams and equipment is one of the reasons the families have such a hard time because they're getting messages from different people. we know there are two acoustic events as they describe them. the chinese ship that found something on april 5th and this other, the ocean shield, on april 6th had something. this is being this credited and forgotten, 373 miles away is

getting all the attention. this is why. the chinese were using a handheld device like this which even the manufacturers say is really not made for the conditions in which they're using it nor the way they were using it. on the other one, the ocean shield, the other location, this was being used. this is the towed ping we've talked so much about here. it's way behind the ship on a long cable moving very slowly. it is a much more robust, much more powerful, much more serious piece of equipment for this job. and this is the one that has given the pings that they're interested in. so even though family members could be very excited by hearing about either one of these devices, this is the one that would actually make a difference. wolf? >> a number of white objects were sighted by various folks out there, especially the planes. 56 miles or so from where the sound was detected from the chinese ship. how important is the search, bottom line, right now, for debris? >> you know, for so long this was the holy grail out there. people were saying, let's find some kind of debris. i think it's arguable now that

it is less important, and the reason has to do with the passage of time. if you think about it, up here on the surface of the water, all of this has now been moving. there was a big storm in the area just days after the plane disappeared. and there have been regular currents. no matter which way it's going, even if you figured it was moving at a rate of one mile an hour which is modest, could be moving two, three, four miles an hour, it could easily be 700, 800, 900 miles away from where it started. so here's the thing. if they think they have wreckage down on the bottom, and they have nothing up on the top, that doesn't necessarily mean anything because what was ever on the top could have long ago disappeared or been washed away. the flip side is also true, wolf. if they do find debris on the top and now know it's from malaysian airline, that doesn't necessarily connect it to anything on the bottom at this point, because there's been so much time and so much movement and all of that adds up to what? just what we started with. more uncertainty and difficulty

for the families who just want to know what happened. >> tom foreman, thanks. let's dig deeper now with sonar expert greg sharvat. greg, thanks very much for joining us. let's say the pings that the u.s. navy detected, one going on for about two hours, the second going on for about 15 minutes, are from those two black boxes? what are the next steps toward actually finding the black boxes, finding the plane? >> well, the next step here is going to be to have to geolocate the source of those pings. i'm sure they have probably already done that already because the tow behind ping detector will likely provide a geolocation feature. they should have approximate depth and location of the actual ping. next step is to send a vehicle down there to actually find the box, itself. >> so how long you think that could take? >> it could take a while. i mean, i think -- let me back up one step here. the other thing they're likely going to do is probably try to

image the area from where the ping came from and see, if they look for some sort of geometric wreckage, something that doesn't look natural, doesn't look like a rock, doesn't look like the ocean bottom or sand. they'll do that first. if they find interesting looking targets, they'll send something down to visually take a picture of it. this could take days to weeks, or longer even. >> yeah. officials say the pings that the u.s. navy detected thanks to that sophisticated towed pinger locator that it was near the 37.5 kilohertz which is the standard beacon frequency for those two black boxes. is there anything else that could make that kind of sound that could confuse those who are searching for the black boxes? >> well, i mean, the sound is very unique. it's going to be a 37 1/2 kilohertz pulse with a specific duration depending on the model of the pinger. if they say that's for one of these pingers, i'd be surprised if it could be anything else. >> that's why they're cautiously

optimistic right now. they're trying to recreate that sound. the past 10 or 12 hours, they have been unable to so, even though there's a 24 hour a day search under way. my suspicion is, and this is my fear, i'm sure a fear of a lot of others that either the two batteries are very, very weak, the weaker the batteries, the less the beacon sound goes out, or the batteries may have died. they're only supposed to last what, about 30 days, now we're in day 31 or 32. what's your sense? >> you know, we could have caught it on the bitter end of the battery life. that's interentirely possible. they're in deep water. varying temperatures. very cold down there. it's possible we may have caught them at just the end and may be very lucky. >> the pinger frequency gets stronger the closer you are to those black boxes, right? >> yes. the intensity gets stronger. the frequency remains the same. >> so if they were hearing for two hours that signal coming out, what they suspect is one of the black boxes, it's important

to determine how strong that signal was during the course of those two hours? i'm sure the experts have done that. don't you think? >> i would think so. i think they probably did more than just that. i think they probably -- they probably plotted the intensity and the phase of that signal over the duration of their tow as they were towing that sensor. with that information, they could actually compute, likely very much compute an approximate position. i would guess that's probably what they did. >> is there any way what the chinese detented could be the same as what the u.s. navy detected even though they're close to 400 miles apart? >> you know, given the distance, it seems kind of unlikely to me that's the same signal, quite honestly. also, the equipment they were using looked on the primitive side. looked like a coffee can and string attached to it, so i don't know. >> bottom line is -- you're an expert on sonar. your sense is the u.s. navy really did hear the pinging coming from those two black

boxes? one lasting for about two hours. one lasting for 15 minutes. the sounds coming from a relatively close location. it seems like that's the real deal, at least to me. >> i would trust what the u.s. navy and australian navy are providing us. i don't know what the chinese have found, but i'll go with what they're telling us at the moment. >> let's hope they're able to recreate that. greg thanks for joining us. >> thank you, wolf. questions about the underwater pings heard by the chinese ship. is the equipment the chinese have really reliable for this kind of search? our own richard quest, he's standing by with his take and whether searchers may be closer to finding not only the black boxes, but the plane. peace of mind is important when you're running a successful business. so we provide it services you can rely on. with centurylink as your trusted it partner, you'll experience reliable uptime for the network and services you depend on. multi-layered security solutions keep your information safe, and secure.

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we're following a 24/7 hunt at sea. crews desperate to find the electronic signals they heard hours ago, signals that might be coming from flight 370's two black boxes. separate pings were detected by an australian ship and michines ship. one discovery might be more credible than the other. ethena jones is looking at this part of the story. >> investigators are looking closely at the signals picked up up by the australians, trying to find them again.

they were using a sophisticated detector, the towed pinger detector provided by the u.s. teams are also still investigating the pulses that the chinese detected. here's more on what that ship found. >> this is an important and encouraging lead, but one which i urge you to continue to treat carefully. >> reporter: words of warning over the weekend from angus houston, head of the international search team, about a possible breakthrough from this chinese crew. which used a hydrophone attached to a pole to detect two electronic signals from what could be the plane's black boxes. the sounds detected friday and saturday were just over a mile apart. but were heard more than 350 miles south of where an australian ship later heard similar but longer lasting signals. >> what i find still odd is the fact we don't have an associated debris field. you don't have smoke without fire. we've never had a crash

investigation where black boxes were found without debris. >> reporter: indeed, questions about the fleeting signals the chinese picked up remain. for instance, how could a relatively rudimentary detector, this one cost no more than $16,000, designed for use in shallow water pick up pulses potentially miles deep? it's technically possible, but not likely says the pacompany tt makes the detector. >> it would be right at the edge of the detection limit of that system. >> reporter: the signals are the right frequency, but the ocean is noisy. the chinese team wasn't operating in ideal conditions. using earbuds instead of more reliable headsets to listen for the pulses. the team was also traveling with a spare pinger onboard which could have been emitting a signal of its own. and the chinese said they did not have time to record the pulses. making a scientific analysis impossible. one thing is certain, china is eager to show it's working on behalf of the 154 chinese citizens onboard flight 370. >> the chinese government wants

to be seen domestically by its own people as doing its utmost to find out what happened to this plane to give closure to their families. >> that last point there is one that all of the experts i spoke with today stress to me. whatever doubts people might have about the strength of the evidence china's provided when it's come to these pulses or pings, whatever conspiracy theories may be out there, the bottom line is that it's in china's interest to do everything it can to help find this plane. that's what these experts say china is doing. >> thanks, very much. let's bring in richard quest right now, joining us from new york. very quickly, richard, what do you make of the chinese single pulse signal? are you giving that any credence? >> no, frankly. the only reason i'm not giving it any credence any more is the experts privately will tell you it's technically possible that it picked it up, but not one of the experts i've spoken to who know about this and look into

this even think it's remotely likely. the pictures you're looking at now, wolf, i believe are designed for chinese domestic consumption. not necessarily -- they're designed to show the chinese involved in the search. this is to show the estimates that they're putting toward. as a realistic ping from a black box, even angus houston last night said he did not believe that the two were related. >> what is a lot more credible, in my assessment, a lot of others, is the u.s. nav navy heg a ping for two hours from one location, another 15 minutes from another location. the u.s. navy saying publicly they're cautiously optimistic. these two sets of pings were coming from these two boxes. i assume this is a lot more credible to you. >> night and day, wolf. the way in which ocean shield

has not only detected these for a sustained period of time, but also managed to record them. excuse me. peg my pardon. managed to record them and sent the recordings to perth where the wave form has been viewed and has been heard and managed to replicate it. it shows a very great difference. now, this isn't chinese bashing. this is science. this is basically saying in this scenario, the assets and the belief has do go at the moment to the ocean shield, whether it's australian, whether it's american, whether it's british, whether it's chinese, it doesn't matter. the fact it has the more sophisticated equipment and has the more reliable data tonight. >> the fact they haven't found any debris before hearing what they suspect are pings from the two black boxes, that's highly unusual, if not unprecedented. >> the word i'm using is troubling because you would have expected to see something. unless the plane is virtually

intact underwater on the bed of the ocean. here's something that tom sater, cnn international weather center pointed out. if you remember, a couple of weeks ago, a gale, a tropical cyclone went through there on the 23rd and 25th of march. do you remember we were talking about how it was going to have to delay and it may even stop searches? well, although it didn't effect the actual search area in the far south of the corridor, that tropical cyclone, according to our weather experts, went right through that area. it churned the sea. it had huge waves. it created enormous winds. now, if that was a small debris field, some of our weather experts at the cnn weather center believe that could certainly have dramatically dissipated the debris, any debris there was because it was such a dramatic weather system,

a tropical cyclone, on the 23rd, 25th of march. >> yeah, that would explain why there's no visible debris to be sure. i want to play a clip for you, this is the australian air chief marshal angus houston talking. listen to what he says. then we'll discuss. >> a short time after the sixth exchange, there was another exchange with a slightly different signal. this was a matter of, i think, about eight minutes after the sixth ping. and the expert team considered this as very significant. they think something happened at that stage and we assess that that's about where the aircraft would have run out of fuel. >> so the pings that were detected by the u.s. navy towed ping locator approximately where the plane probably would have

run out of fuel, this sounds like they're on to something extremely significant. >> absolutely no doubt. what he's talking about where the famous inmarset handshakes. we know they were at every hour except that last one, wolf. that last one was just eight minutes later. we also know from handshakes earlier that there was a handshake every hour all where there's some event. possibly major change in altitude. where the airplane tries to reconnect to the satellite. what he's saying is that that last half handshake that has always troubled us, that has always given us cause for what was it all about? is that where the plane went down? is that the moment of extremise? now he's saying all roads converge, all tracks come together. the increased integrity of the inmarset data, the 6 1/2 handshake ping. the location in the ocean at that part of the corridor, and finally the virs various pings

from the pingers, not just one type, but from both of them twice. there is a confluence of events around what's happening there at the moment that has to raise this to the highest levels of integrity and credible. >> i think they are clearly moving in the right direction. we'll see how long it takes to finalize them. thanks very much, richard quest, reporting for us. just ahead, we'll have much more on the plane, but also the crisis in ukraine. now it's intensifying in the eastern part of the country. we're going live to russia for what's going on. plus, as i said, we'll have more breaking news coverage of the search for flight 370. what one official is now calling the most promising lead yet.

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now for malaysia flight 370, that's coming up in a moment. first, another important story we're following, the crisis in ukraine, now intensifying in the eastern part of the country. cnn's phil black is monitoring the situation for us in russia, not far from the ukrainian border. phil, what are you picking up, what's the latest? >> reporter: well, wolf, we know that a number of major cities in the eastern part of ukraine, pro russian protesters have taken over. some of them are calling for russian help, russian intervention, calling for a referendum to declare independence or join the russian federation. just like crimea did. and the ukrainian government is accusing russia of directly orchestrating these events, controlling these protesters, effectively trying to create a pretext for military intervention and further annexation in parts of ukraine. now, the russian government

says, don't blame us for all of your problems. they insist they are pushing for a diplomatic solution, bringing everyone together to come up with a new constitution that will keep everyone happy. very different to what was the russian position until very recently, that they have the right to take military intervention in order to protect russian-speaking people in the east of the country. and clearly, there's still concern that could be russia's intention, because the state department says, secretary of state john kerry said exactly that to his russian counterpart, sergey lavrov, warning russian again not to invade further parts of ukraine, warning there will be serious consequences, and very much stating the belief that it appears there is a russian hand in these events that are taking place in the east of ukraine today, wolf. >> yeah, this crisis, clearly, escalating right now. we'll stay in close touch with you, phil black, on the border between russia and ukraine. just ahead, more of the breaking news coverage on the search for flight 370 and why the u.s. navy is, quote,

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this just coming into "the situation room," the u.s. senate voted to restore jobless benefits for the long-term unemployed that ran out in december. the vote, 59-38, the measure would affect more than 2 million americans, but the fate in the house of representatives is not clear. house speaker john boehner says

he opposes the bill, because it doesn't create more private sector jobs. we'll stay on top of that important story. we're also following all the breaking developments in the mystery of flight 370. crews are now searching the waters off australia around the clock. they are trying to relocate electronic pings consistent with signals from a jet's black box. a commander tells me the u.s. navy remains cautiously optimistic about this lead, but the caution is increasing every hour that they don't hear those pings once again. the batteries, by the way, in the two black boxes for all we know may already be dead. they are due to run out about now, a month after the plane took off and then vanished. without battery power, the pings would stop. they are supposed to last, what, about 30 days. they could last a few days longer, so there's a desperate, desperate search right now to find those two black boxes.

that's it for me, thanks very much for watching. you can always follow us on twitter, go ahead and tweet me @wolfblitzer, tweet the show. "erin burnett outfront" starts right now. next breaking news, searchers racing to confirm the pings heard in the indian ocean are from flight 370. a report from the u.s. search team in just a moment. plus, the agony of waiting, the brother of an american passenger "outfront" tonight, why he thinks investigators may be hiding something. and oscar pistorius takes the stand, talking about how the smell of blood still haunts him. let's go "outfront." good evening, everyone, i'm erin burnett, and "outfront" tonight, breaking news. ships so far have failed to reconfirm the signal that could be from black boxes belonging to