most of the folks that fly are still in the same belief that i am, that radar is constantly with us in some form or the other and never quite far enough away from it where we couldn't be tracked or low enough to be tracked. we're just an obvious target out there. >> stand by, everyone. there we go. i'm don lemon. you're in the "cnn newsroom." we're at the top of the airline. we have to make very critical decision and do it soon, when to turn off the ears and start looking with eyes. we're talking about below the ocean floor, not on the surface. i'm talking about those pingers, those emergency beacons believed to be at the bottom of the indian ocean. if the batteries aren't dead already, they soon will be. a high-tech imaging sonar is the next school to start running when commanders decide to stop listening for those pings. it has been four days since the sound has been heard from the deep ocean in the search areas. so the prime minister told

reporters today his confidence remains high despite the many challenges. tony abbott described a multinational search as a massive, massive task. and the search planes, they're at it again. they're up in the air again departing from perth in western australia. today marks day 37, 37 days since malaysia airlines flight 370 vanished. live now to perth, australia, cnn's michael holmes. michael, the prime minister tony abbott says he is still confident about the search. what about the search crews, do they share that optimism? >> well, they share a determination to keep on going. i think it's fair to say, don. optimism about finding wreckage now certainly on the surface, boy, that's got to be wearing thin. i mean, just imagine, we're into the sixth week now and they still haven't found one piece of wreckage. they are continuing to tow that ping locator on the ocean shield vessel and that smaller search area. smaller than it's been.

there's also the "echo" there, a british ship that sends down its own sonar and tries to pick up any hard objects on the bottom. but, yeah, you've got to think and you were just saying this and you're right, don, you've got to think it's got to be only a matter of a day or two before they say those pingers are dead now and we've got to use the information we've got. and send down that submersible and have a look on the bottom and see what we can see. tony abbott, the australian prime minister, he's right when he says it's a massive, massive task. even going down and having a look under t water, you're talking about a vast area still really and submersible that moves literally at walking pace. he also said something else. he talked about the relatives of those missing aboard that flight 370, and he said if they want to come to australia, want to come down and be close to where this plane ended its journey, then they would be welcome. have a listen. >> at some point, with the

agreement of families and the interested governments, we would like to hold a memorial service. and down the track, maybe build a suitable monument. but this is the kind of thing that we would want to be in close consultation with families arou and with governments about before we finalize. >> meanwhile, don, the search does continue. a dozen planes are going to be up in the air today. 11 military, one civilian, and more than a dozen ships. you've got those two, the hms "echo" and the "ocean shield" looking in that area where the pings are heard and other ships that are out hundreds of miles to the west because that's where the experts have worked out with the way the ocean moves and the storms that have happened over recent weeks. that's where any wreckage would be if it is still floating. the weather is going to be pretty good out there. they will be flying at 200 feet. and just sort of see if they can

see anything. but as far as the pingers go, don, i think you're right. i think time is running out for those now. >> they haven't run out already, thank you, michael holmes. appreciate it. i want to bring in cnn aviation analyst and retired british royal air force michael michael kay and les abend and there at the end, famed ocean pioneer jacques cousteau and also fame noud in his own right. cnn analyst and ocean expert, david gallo. welcome to the panel. thank you for coming in. i just had a conversation, actually, with -- what's his name? the other cousteau. >> which one? >> jacques, fabian. >> sebob. >> a small group. >> i wanted him to come in and talk about it and he's working on a show and he will come in i time. so, listen, i want to start with that part of the world is

considered extremely, extremely -- it's considered extreme, right? i should just say an extreme part of the world. how long can they keep looking? forever? this is very costly. you have a lot of people out there tiring themselves out. >> that's just it. you're talking about trying to find an object like the you were looking through the front door keyhole to see what's going on up in the attic. that's how clueless we are about this area. we have limited access to technology, although the technology that they're using is fantastic, of course. but there needs to be a lot more of it. and beyond that we just don't know the topography and it's really a pretty remote area as far as the general part of the world is concerned. to think about it, the ocean represents 3.4 billion cue bibb kilometers of space within which we've only explored maybe 5% if not less. >> do you think we need more assets out there?

>> with more time and enough finances, we can pretty much find anything in the oegceans. but look what happened with the "titanic," it took us 73 years. with air france flight it took three years. and we knew approximately where it went down. this may take a long time. >> even though you knew where it went down. amazing. you're looking for a ship as big as the "titanic" and it took 73 years. very good point. it is day 37, right? we are talking day 37. you heard what we h said, it took 70 something years. the pingers are supposed to last about 30 days. i mean, how should search teams keep listening? what is the cutoff? 37 days, 40 days, how long until we exhaust it because they can last as long as 40, 45 days. >> well -- sorry. >> no, i was just going to say it really just depends on the process and the determination. just because the pingers go out doesn't mean you stop searching. it just means the search is much

more complicated. >> right. and then there comes a point in any search, right? i don't think we've reached that point yet, but where the assets start to back off. >> right. >> and people come up with assumption, it is, we are what we can assume is that flight 370 went down in the ocean and it has not been found and we are backing off the search. that's just normal. >> mia, lost at sea, and a write-off. >> right, absolutely. >> but there are so manies assets out here and so many countries and people determined to do this. that in of itself seems unprecedented. >> if we make the assumption is that we are going to find it, it's just the journey of getting to the location. i think if we listen to the hard facts and the experts say the batteries at the very far end could possibly last up to to 40 days, i think it would be sensible and pragmatic for angus houston to go to 40 days, maybe a couple of days beyond just so he's absolutely confident when he deploys his auvs he's

exhausted every opportunity to locate a ping through a ping locator. that's important. in angus houston's mind he's got to be 100% confident that he's done everything to locate the pirng before he goes on to the next phase. >> dadevid gallo, what say you? >> quitting is not an option. it's the family and loved ones of passengers. it's the flying public. it's the aeronautical industry. so quitting is not an option. and again, we're not intimidated by the depth, we're not intimidate bid the terrains. it's a matter of having the right team. it's a matter of having the right technologies, the right operational plan. and then we've got to let them do what i do best and in this case we've got a good team out there, they're great. they need to start making a systematic map of the seafloor and little by little paint that area in until you find the bits of that aircraft or the aircraft in one piece if it's there. >> david, you mentioned just in the previous show that you said you're not -- in this show you

just said you're not intimidate bid the depths. but then you said i think on other side of australia that they're working twice the depths of this one. >> sure. >> why aren't they doing that here? >> one is a scientific mission. it's called -- a brand new initiative called project hadal which means really the ocean. and we've got a new type of robot called nerius that can go down to the greatest ocean depths, even the same depths that james cameron dove to. but that's a scientific mission where everything has been planned out for years. this one on this side is much different. we're after a specific target, finding bits of an aircraft and retrieving two black boxes. so the only difference really in my mind is one side is driven by scientific question. this side driven by aircraft investigators. >> fabian, all four signals detected within 17 miles.

it seems relatively small area. do you agree with that? >> depends what you -- when you say 17 miles and you think about 17 miles at -- but then three miles deep. >> right. in the grand scheme of things it is a small area. it's still a very large area in terms of the search pattern. >> yeah. someone -- i heard someone on the air yesterday, david, it may have been you, saying, okay, so maybe, you know, maybe within 17 miles of each other they have, you know, narrowed the search area down to a couple hundred miles. but think about that when you're looking at -- from an airplane, right, t, what is it, 30,000 feet or maybe a little bit lower. and look at the size of a bus and then trying to do that in the dark. to locate that. >> yeah. >> and that's -- there you have it. >> it's a great -- great way to think of it, don. when you get out there on the ocean, it's a whole different world beneath the sea where nothing happens very quickly. and the deep sea, we don't have

gps, we can't use radio waves, we have to bring our own light, our own power. and there are no maps. i'm looking forward to the maps that "echo" will produce. i'm sure they will be fabulous. i think that will give everyone a bit of a boost because that will show the underwater terrain in incredible detail and give us some sense of it's a workable place. so these are things, again, that oceanographers deal with, all of these things routinely. i'm not saying it's easy. it's not easy by any stretch of the imagination but it is nothing that we're unfamiliar with. >> all right. we're going to continue on in this and talk about the bluefin-21, speaking of going to the depths of the ocean. if search crews are finding the wreckage of malaysia flight 370 this submersible will provide the first images of it. here's the thing. it's currently sitting on the deck of the "ocean shield." why not deploy it? we talked about it. it's the sound. maybe it will be deployed very shortly.

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so right now the bluefin-21 is sitting on the "ocean shield" waiting to be sent on its mission. skip is asking what many viewers are asking, you will have to use the bluefin so why not just use it now? you have already lost pings, why the waste of time? listen to what william marks says. >> once you get the bluefin in there it's actually taking a picture of the bottom of the ocean floor using sonar cameras. so imagine walking but then every few feet stopping to take a picture of the ground. so that is a much slower, more deliberate, methodical process. once that starts, we're in it for a good chunk of time. so we really don't want to start that until we have to. and anything we can do to even narrow this sector down even a little bit will be hugely beneficial for using the bluefin. >> okay.

let's discuss with our panel now which includes audio expert paul gensburg and jeffrey thomas, managing director of airlineratings.com and david galoo, fabien cousteau and that british guy, michael kay. jeffrey, i want to start with you first. if not now, when? seriously. many people are asking that. jeffrey? >> sorry, john. yeah, look, it's a very good point. and one of the things that we possibly are under playing a little bit here is the role of "hms echo," the graphic ship because that is surveying the bottom with an echo sounder and the bottom as we know is silt and they're hoping for a stronger return from, say, a large metal object, the

aeroplane. and that would obviously narrow it down dramatically. but even if it doesn't pick up anything, it is sweeping the floor, possibly eliminating the areas where we don't need to put the bluefin-21 down two. >> michael kay, you're giving him the thumbs up here. why? >> geoffrey is spot on. three days in the context of a search that could last for years, i don't think we are wasting time. what we're doing is, angus houston is making absolutely unyou've kabquiequivocal 100% s all the possibilities. as soon as you put it in that's it, we're in the for the long haul and it could take years. >> why is there only one bluefin side scanning sonar? why can't we use five or six of these to search faster? i think that's a david gallo question. >> good question. we had three similar vehicles.

we had the rema 6,000, three of them on board one ship for the air france 447 search. we had two of them on the last "titanic" expedition along with an rob. so we had from the same ship multiple -- multiple auvs, or underwater drones. it's a tricky operation. it takes time to learn the ops, how to do that. i think before they shipped that vehicle they thought of what the use would be and that's what they decided. so, again, i'm not going to second-guess the team out at sea. i think if they need more vehicles like that they will bring them in. >> okay. >> that's a great question. >> another viewer asked, why if they had a ping for two hours didn't the ship stop and drop the bluefin at the time? >> i think just because they hear it they don't know the exact location so they just can't drop it there. right, fabien? >> you described it correctly. it's not like a gps pinpoint.

you know, sound travels much faster underwater which makes it that much more difficult to triangulate, as miky said, where this ping is coming from. then you the complications of water, temperatures that bend those sound waves, as well. so it's much more complicated than what it sounds like. and then you've got, of course, the limited range, these rovs and auvs like the bluefin have in the case of a bluefin, maybe 24, 25 hours of time at 3ish knots which is actually fairly slow. it's like trying to find a needle while you're taking postage-size pictures of the bottom in a field the size of long island.licatecomplicated. >> paul gensburg, audio expert. does it concern you that we haven't heard anything in four days? >> well, it does. it really gives us an indication

that we have it looks like come to the end of the lifetime of the batteries. certainly hope springs eternal, we would like to hear them some more, but right now, no doubt, all of the engineers aboard the ship are doing an analysis and using enhancement techniques to exactly determine what they heard and which were pings and which weren't. >> okay. here's a question, right? so the thing that we got from the jacc, which is a coordinating task force there, says yesterday's search field was a 41,393 square kilometers, about 2,071 miles. today it's about 35,700 miles. we have been saying that the search area is contracting. it's expanding. >> it's a airport search. we have to be very clear that there are two key searches going on. one is subsurface and one is on

top of the ocean. >> do you think that's the airborne search for that? >> well, i think, you know, we already touched upon today. you got the pas, p3s and the 76ers. >> the authority has planned a visual search area totaling the center of the search area lies approximately 2200 kilometers northwest of perth, is what they're saying. but so, even the visual search area appears to be expanding. >> yeah. i mean, the crews will be searching a specific area and then eliminate that and then using modeling and information data from the people who are all over the currents and the tidal flows. that's the way it will be working. it's incredibly complex just because they search a specific area doesn't necessarily mean the area will contrast, which is the area is so huge. and again, they're going back to the remodeling days for the miramar and everything else, there are so many factors to pull in. so i think what we shouldn't do

is get confused with the airborne and subsurface area locations. they are very different. the operations are very different. it's not as simple as searching somewhere airbornewise. stick around. much, much more on the mystery of flight 370 coming up. but also a developing story to tell you about. gunman seized two buildings in ukraine. the escalating crisis and the we got a subaru. it's where she said her first word. (little girl) no! saw her first day of school. (little girl) bye bye! made a best friend forever. the back seat of my subaru is where she grew up. what? (announcer) the 2015 subaru forester (girl) what? (announcer) built to be there for your family. love. it's what makes a subaru, a subaru. how much money do you think you'll need when you retire? then we gave each person a ribbon

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more on flight 370 just ahead, but new developments i want to tell you about in the crisis in ukraine. the white house wastingly time to responding to new reports of violence in the eastern part of that country. it is sending vice president joe biden to the capital of kiev on 22nd. a pro-russian separatist storm buildings in a city -- at least two cities, excuse me. police exchanged gunfire with pro-russian activists. about 20 men wearing matching military fatigues took control of the city's police headquarters. just about 70 miles away gunman stormed two buildings including one building to the police. three officers were hurt. the response of the white house, the spokesman said the administration is very concerned about russia's actions in ukraine and decided to send the vice president to talk with government leaders and other groups. part of the white house

statement, the vice president will discuss the latest developments in eastern ukraine where pro-russian separatists apparently with the support of moscow continue an orchestrated campaign of incitement and sabotage to destabilize the ukrainian. state. and just moments ago we learned that secretary of state john kerry spoke with russian foreign minister lavrov on the phone. kerry says he expressed strong concern that attacks today by armed militants in eastern ukraine were orchestrated and synchronized similar to previous at tacks in eastern ukraine and crimea. if russia does not take steps to de-escalate the situation. as investigators listenusiv the the only thing making noise under the waves. they listened for a pinging signal with underwater microphones and heard much, much more. [ hypnotist ] you are feeling satisfied

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right now search planes are in the air on this the 37th day since flight 370 went missing up to 11 military aircraft, 1 civil aircraft, 14 ships involved in sunday's search. we keep hearing words like optimism and confidence related to the hunt for flight 370. but pings that are thought to be from the plane's black box haven't been detected since tuesday, leading to fears that the batteries in the data recorder are becoming too weak to transmit. relatives of missing passengers pet today with malaysian officials. one mother says she feels like the malaysian government has forgotten about all things connected to flight 370. right now the u.s. navy's towed ping locator is scouring a narrow section of the indian ocean. over the past week, four

possible black box pings have a lot of investigators to narrow the search area. so far they've dn unable to relocate the sounds. one of the reasons is the association is such a noisy place. other sounds under the surface could be drowning out any signals coming from the data recorders. cnn's rosa flores took a pinger out on the water to let us hear some of the obstacles they may be encountering now. here she is. >> reporter: this is what a ping sounds like. >> very high frequency. >> reporter: the critical sound searchers are hoping to hear in the deep and rough waters of the indian ocean. >> it's deep and it's dark. it's salty. it's high pressure. it's hard to work. >> reporter: here in rhode island's bay researchers show us the challenges search crews face as they try to hear the ping from flight 370's data recorder. >> so this is a hydro phone.

>> reporter: we drop an underwater microphone, a hydrophone off the back of the boat as it moves farther away from a pinger that's already been submerged. and even less than 100 yards away, the ping starts to fade. distance isn't the only problem out in the indian ocean. there are other noiszs competing with the sound of the pinger like sea life. one dolphin species sounds like a black box pinger. and this the sound of rain under water. let me get away from the loudest part of the boat so i can show you one of the biggest obstacles that searchers in the v. in the open sea, just ship noise, even here listen to how loud it is. >> they're at a minimum 15,000 ships on the world's oceans on any given day. creating even more obstacles in a search that's already

daunting. >> rosa flores joins me now. rosa, what did the researchers think about the pings found so far? do they think that it is consistent with the national ocean sounds or the mh370 pinger? >> you know, don, i talked to ocean gra f oceanographers in several states around the country. they say the first pings that we heard from the chinese, those were probably sea life, they say. and they say that because of the duration of those pings. these latest pings that we've been talking about, these four pings that have long durations, all of the oceanographers say that's very credible, that's very consistent because of the length of those pings. don? >> rosa flores, thank you very much. fabien cousteau is sitting here nodding his head. >> when we talking about the white noise complicating the

search, of course, there's the ocean surface, so you've got all the garbage we throw in our oceans which definitely throws an obstacles for that search, for that visual search at the surface. and down below that surface there's something called noise pollution. and manmade noise pollution is certainly a factor in all of this, as well as just the natural ambient noises that nature makes. >> manmade noise like what? >> low and mid-frequency sonar, for example, that have been known to enter fointerfere with migrations. beyond that it just creates a huge soup of noise. >> thus, the issue with putting the sonar in there now because you get that frequency. let's find out a lot more about this, about sounds with this precious ping among all that random noise requires huge amounts of skill. audio experts looks at gazillion of sounds just to find one black box ping. we have someone here to show us the use in the search for pings.

i'm joined again by awudio expet paul gensburg. some might sound blurry or insignificant. show us the audio experts how they tell the difference. >> okay. what i've done is prepared a simulation for you. first i have a pure tone as if it was coming from a pinger. and we can play that. nice and clean. right? but, once we submerge it down three miles and we start to listen from the surface, we're going to hear it embedded in ocean noise. >> you can barely hear it. >> that's right. and if you don't know what you're listening for or if you're not in range you won't hear it. >> can we put that one up again? let's put that one up again, paul. this is what it sounds like and you're wondering about the sound

and why they -- >> why they have trouble hearing it. >> is that ocean rain or is that just how the ocean sounds? >> no, this is a simulation using a largeme amount of white noise. in the ocean we have white noise but also, as fabien said, a lot of other manmade noises and natural sounds. so what i did was, i employed some forensic audio techniques, some of which were the same that i used in locating the gunshots in the sandy hook shooting 911 tapes. and i want to show you and let you listen to what one level of enhancement of the signal would sound like. you can begin to hear the one-second repetition rate. >> okay. >> okay. of course, knowing what the frequency that we're listening for helps so that we can craft

digital filters and so on. and that makes it a little easier to -- to ascertain what we're listening to. okay. finally, another round of enhancement using more tools in our tool box and we'll get something that really sounds identifiable. with the exact repetition rate of one second and the period exactly stable. >> okay. >> now, just so you know, under the ocean there are lots of different paths that the sound can take. and the effect of this is multiple sounds reaching the receiver which would tend to make echos and make it not as distinct. and that's some of the problem that they have in identifying these sounds. >> paul, that is fascinating. when you were here last week,

we're so glad -- we learned so much from you, every time you come on. so let's -- let's do it again in order, guys. so this first one is what they're looking for no, enhancement. and then you can hear exactly why they have so much trouble. that's a clear -- that's clear -- that's the one that it sounds like right out of the water. that's the way it's supposed to sound. >> correct. >> and the second one is -- >> that's where we begin. pretty noisy. >> can you imagine listening for that? you know, hours at a time and 12-hour stretches at a time? and one this one is a little -- a little bit of enhancement. >> correct. correct. >> okay. and this one is -- >> this one is the final version and, of course, it could even be improved upon more if we needed

to to make precision measurements in the period to identify what we're hearing. >> and they can do this out on the ship? can they enhance like this out on the ship? >> hopefully. i expect they can, yes. there are special forensic software packages that allow us to do this on the fly. >> okay. stand by. we're going to continue our conversation on the other side of the break. and my panel of experts will weigh in on this. we'll be right back. mr. clean likes to keep things simple. that's why he brings his magic eraser extra power. it quickly cleans hundreds of different surfaces. so you can get back to doing what you really want. the magic eraser extra power. ♪ the magic eraser extra power. making moves that would put an adult in the emergency room. yet all they really want to do is grow up. it's funny, everyone i know wishes they could go back and feel younger. sound familiar?

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also with audio expert paul ginsberg who has been giving us excellent examples here. you gave us an unenhenced ping and also enhanced. you have a question for him. >> the point you make on filtering enhancements is fascinating. i want to get a sense of how long that process of analysis takes once you actually get the initial recording. >> well, one of my professors in college once said, if you do 90% planning you only have to do 10% work. and i've always loved that quote. and so the way that applies to this problem is, you need to know how to characterize what you're looking for with respect to frequency, duration, and periodic rate so that you can tailor your filters to accept

only that type of signal. once you do that, you've stripped away so much of the job and the work and you can get to it much faster. so a lot of the -- a lot of the key aspects is the preplanning, the proactive bit and that will reduce the timelines afterwards. >> absolutely. >> got it. >> remember -- >> go ahead. paul, sorry. go ahead. >> i would say, i would love one of the manufacturers of these pingers to do experiments, listening, recording, in various different depths, even in different parts of the world, and make charts and recordings so that we could analyze so we could then know what type of filter that we need to use under different circumstances. >> so geoffrey thomas, in perth, why is there this big delay, this big delay. and now we see why, because, as the audio expert is saying, the -- all the differences made,

the important part is in the preplanning and that's what they were trying to get together in the initial stages of looking for these pings. >> no doubt. >> looking, the example that's been shown than extraordinary. and we're all getting some very interesting lessons in oceanographers and acoustic sounds. what we're seeing at the moment in this very small search area, not the large one but the very confined one, we're seeing the ocean shield go through with the pinger -- towed pinger locator. it does a sweep through and then exit the search area and then hms echo comes in behind it and it's doing methodical echo sounding search on the bottom as well. i think they're putting a lot of hope in the fact that -- first of all, getting some more pings, obviously. but that hope is fading fast. they're also hope that "echo" will pick up something on the bottom or if nothing else, eliminate an area where there

was no positive return off the bottom so when they do put the bluefin-21 down the area is going to be reduced even further and make this pain staking process just that little bit shorter. >> yeah. absolutely right, geoffrey thomas. >> i was fascinated to continue to conversation with paul on the proactive piece. paul, if you are still on, how much does temperature, solidity and pressure and all of these thermal layers in the depths of the ocean, how much does that affect the process being proacti proactive? >> that was last week's lesson, but go ahead, paul. >> sorry. >> in review -- well, there is, you know, everything changes. wherever we are, we have to try to make models but we don't know exactly because, as you know, weather plays an important role,

the tides, the current, and so on. so you have to try to plan as much as you can but then tailor it when you see what the actual conditions are. and that's important. another point is about the power of the pingers. the power of the pingers is approximately, i believe, a tenth of a watt and it's pulse sod that the battery life is extended and we're only really a miles from it and we're receiving echos from different parts because of the thermal layers. >> can you tell a sorry about how sound travels really quickly? okay. my producer is telling me to do it after break. paul, don't go anywhere. panel, don't go anywhere. we'll be right back. (mom) when our little girl was born,

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we're back now getting a very fascinating lesson in acoustics and listening for black box pings. okay. so the first one is just how the pinger sounds when it's not in the water. and then the next one is what they are hearing out in the ocean unenhanced. believe it or not there is a ping there in the background. this one is one level of enhancement.

and since they know the frequency, our audio expert paul ginsberg says they can do this with it. paul is here with us giving us a valuable and fascinating lesson in audio. paul, we're talking about traveling, what did we say, 17 miles group said you had an experience just recently that demonstrates just how far sound can travel. >> okay. well, actually it was when i was a young man and i was riding across the triboro bridge in manhattan and i had a c.b. radio i converted to the hamm radio frequencies. it was only four watts. that's the power of a night light. and i was able to contact a fellow in a sailboat off the coast of australia. and we spoke for ten minutes. i put my hood up and pretended that i had broken down. i guess i should apologize to the cars that were behind me at

the time. but the reason that we were able to make communications, contact, is because of the reflection of the different layers of the atmosphere. otherwise, signals could just have gone into space. but rather, they go around the earth and so on. and so it is under the water where there are reflections from different thermal layers and different solidity areas. we have different gradients, temperature, and solidity. and those form walls, as it were, to reflect the signals and make echos. if there are too many echos it a k. really produce a fuzzy image that makes it very difficult to ascertain what you're listening to and certainly to measure the beginning and end of a pulse. so that's what they're dealing with. they've got considerable job ahead of them. >> can you stick around and anchor the next hour for me? i mean, we're all sitting here

like -- just sort of amazed by the knowledge that you have and the way you explain it. it's really wonderful. what you're saying is that you're not surprised that they may be picking up sounds from further off than one might think. >> i'm not surprised and i also have very deep respect for -- an admiration for the people who are doing the job of trying to analyze these sounds. it is not cut and dried. this is difficult task. >> and there's a speed factor, too, in terms of sound traveling under water. paul, can you give us a reference on that? >> well, it really varies from warm to cold and, again, the movement of the water. and this is why i would love to see a handbook written as a result of experiments done and

trials in various depths of different waters recording all of the -- all of the different characteristics of the water and terrain for each of them. >> paul, we've got to go. >> yes, sir. >> all right. >> okay. >> we've got to go. we're going to save it for next hour. it's has been 37 days and no sign of malaysia airlines 370. if wreckage is found, is malaysia up to the task of solving this mystery in that's next. bloating? one phillips' colon health probiotic cap each day helps defend against these digestive issues with three types of good bacteria. i should probably take this. live the regular life. phillips'.

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you're in the "cnn newsroom." i'm don lemon. thank you for joining us. sunday morning in the designated search area, 1300 miles off the coast of usaustralia. again, like the day before and the day before, they're looking and listening for any sign of malaysian flight 370. we just heard from the search headquarters that 12 airplanes in all will spend the day

visually patrolling the ocean surface while 14 ships will sweep the deep water listening for sounds. australia's prime minister says there's not a moment to spare. >> what we're now doing, given that the signal from the black boxes rapidly fighting what we have now doing is trying to get as many detections as we can so that we can locate -- so that we can narrow the search area down. >> search crews both in the air and on the sea have confirmed zero audio detections in the past 24 hours. one group of people's whose patience ran out hours ago are the families. a group of them met again with airline and malaysian officials. the mother of a missing passenger is not happy. she says they keep telling her the same things, nothing useful. cnn's michael holmes is in perth, australia, right now. and that's where this massive multinational search mission is being run. michael, this is