i want to thank all of my guests tonight. tonight. we'll see you here soon on cnn. -- captions by vitac -- www.vitac.com tonight in the united states. we have new developments tonight in the disappearance of malaysia airlines flight 370. the best evidence suggests the boeing 777 flew into one of these two areas and was still being tracked by a satellite more than seven hours after takeoff. that's hours after the first officer's seemingly routine sign off essentially just saying good night. hours after the plane's radar transponder signal vanished, hours after acars stopped sending data, hours after it possibly soared to high altitude and then plunged 20,000 feet and then climbed again. we learned today that in all those hours authorities say there is no evidence, none at

all, of anyone trying to make any cell phone calls or send any texts or make transmissions at all from the airliner. the question is why not? is it simply the plane was too high? we also learned that other countries are planning for the possibility this plane landed somewhere and is being somehow being prepared to be used as a weapon. israeli air traffic control went on higher alert today as a precaution which redoubles the scrutiny on who took control of the airliner. was the crew up to no good? they were seen in a widely circulated youtube video, the first officer and captain going through security. new attention as well on who, if anyone, had access to the plane's below decks electronics bay. that's what it looks like. the panoramic view shows row after row of navigation and communication equipment including the acars system which either failed or was disabled. and if it was the latter, if it was the latter, disabled by someone who knew which plug to pull, which system to take offline, which circuit breaker

to take off, first, because there are so many theories out there, so many conflicting reports from authorities in malaysia and elsewhere, we want to start with what we actually know. jim clancy in kuala lumpur joins us with more. jim, yesterday there was a lot of reporting that the pilots had turned off the acars system on purpose. that now has changed, right? >> reporter: it has changed. and you know it's -- you know, you talk about the facts. the facts change when that changes and this is why so many people have so many questions about this entire investigation. we were led to believe that the last transmission, and it's true, the last transmission by the automated system that reports on the health of the airplane, acars, came at 1:07 a.m. and then all transmissions stopped and the pilot then -- or the co-pilot we know now, it was the co-pilot who said "all right, good night" at 1:19.

now, this led people to believe that, you know, if he reported everything okay even after this system was off, you know, this points a finger at the pilots. the prime minister believed it. listen on friday as he describes this. >> these movements are consistent with deliberate action by someone on the plane. >> reporter: all right. advance, we're at monday now and we hear from the ceo of malaysia airlines. well, maybe not, because while the last transmission was at 1:07, the acars system wasn't supposed to report back for another 30 minutes, 1:37, well after the time that the pilot said "all right, good night." listen to what the ceo had to say yesterday at the press conference.

>> the acars -- last acars transmission was 1:07. okay. we don't know when the acars was switched off after that. it was supposed to transmit 30 minutes from there another transmission, but that transmission did not come true. that was the very last transmission was 1:07. >> reporter: okay. didn't come true. but here's the point. the pilot said "all right, good night" at 1:19. we know that the transponder went out at 1:21. we don't know that acars was still operational. we don't know that it had been switched off by the pilots. everybody has been pointing a finger at the pilots because they thought they purposely turned that system off. not true. it wasn't supposed to report. we don't know that right now. this opens up the possibility, the possibility once again of catastrophic failure.

1:19 the pilot says -- the co-pilot says "all right, good night." two minutes later, everything goes haywire. he's in a situation trying to control the aircraft. we know it was going up or down. we know right then they tried to turn back. the transponder went off. acars never transmitted again. it's a different scenario, we're back to looking at catastrophic failure. the one problem with that, anderson, how does a plane that has a catastrophic failure go on to fly seven more hours? there's also a window for the hijack theory but a very narrow one. this is going to be something that's going to be debated all day today and well into the future. anderson. >> jim, thanks very much. and it could be mechanical failure, not something catastrophic, not suddenly instantaneous as the plane did continue to fly. it could be something pilots were battling. that's another option. we've got experts in every aspect of this. david gallo who co-led the search for flight 447, fran townsend is here, former homeland security adviser and 777 captain, les, joining us as

well. les, you've been flying for nearly 30 years. as you look at this, given what we know, the transponder was off, as we said, that went off at two minutes after the last communication at 1:19. 1:21 the transponder goes off. we know the 1:37 a.m. acars system that was supposed to send a message did not send a message so that acars system, last one was from 1:07. you talk about this compartment below the cockpit where the system is located and we've got this tour of it here. can you talk to us about what you think was most likely to have happened here given the complexity of this whole system? >> well, that's a good point, it is a complex system. as pilots trained on this airplane, we don't know -- we know what the system does for us but to know every detail down there, i mean i'm considered an expert.

i don't know every detail. i don't know every box. i would really have to study some more engineering and schematics to really know what everything does down there. >> as a pilot, would you be able to turn off the acars system? >> i'd have to climb down there and figure out which one of these boxes would do it. >> so it's not something isn't routine training that you would learn. >> absolutely not. but as far as your question is concerned, i've always asserted that there was some type of mechanical issue that started, as we talked prior to our show time, that might have progressively gotten worse and worse where the pilots were trying to go to a checklist and determine what the problem was by troubleshooting it. >> the notion of catastrophic -- of catastrophic incident, that depends on how you define catastrophic, but something instantaneous, something sudden, being blown out of the sky which is what a lot of people thought early on. that seems to be ruled out if you believe the satellite data that this plane was flying around for hours afterward. but there could be some kind of

mechanical failure, fire on board, for instance, which gradually shut down systems or the pilots felt like they had to shut down systems, correct? >> anything is up for grabs at this point. we can go back to twa 800 where it was attributed to fuel pumps in one of the tanks, because of dry tanks to ignited the vapors. that could be a possible scenario. i very much doubt it because these airplanes have been modified so that never occurs. but, you know, when we talk about catastrophic failure, it progressively might have turned into that where they were trying to troubleshoot the system. if this started to slowly degrade all the avionics and internal communication system and flight controls things would get haywire. there's an electronic checklist that's a tremendous system that we utilize with a touchpad screen to go through an abnormal situation. if they were trying to find this and that screen went blank, now they have to refer to a standard, let's call it a paper checklist.

and now it's an abnormal on top of an abnormal and they have got a real tough situation on their hands. but once again, it's conjecture, i don't know. but i still assert from the very beginning that they were dealing with some sort of problem. >> fran, you still think, you still look obviously at the terrorism angle or sabotage angle, some sort of human involvement here. the questions i've had, and we talked about this before the program, is if it did land somewhere, wouldn't somebody's cell phone on that plane once it was back on land, near you would assume some sort of radar installations, at least be able to be tracked or make some sort of -- unless all the phones were somehow taken? >> right. you've got to -- what does that scenario look like? what are the facts that you need for that to be so? you'd need a runway that's at least a mile long to be able to land it. you'd have to be able to hide it. before you landed that aircraft, you would have to either have confiscated the cell phones of everybody on board, likely somebody would have secreted one or you would have had to have killed everybody on board before

you landed that aircraft. then you get it landed. you're going to need presumably the assistance of a foreign government where you've landed this plane to help hide it. it's a big airplane, it's not going to be easy to hide it because there's satellite images. everybody in the world is looking for it. so while people talk about is that possible, i think it's very unlikely. this plane based on what we know now flew for a number of hours after it disappeared. and so you've got to wonder, even if there was this mechanical failure, why would it be that that plane would have stayed in the air? why would the pilots have looked for the ability to put it down? could they have been overcome? could there have been fumes? could there have been some medical issues? >> do you buy that this plane was flying around? do you buy the satellite and radar information? >> i don't, not with all the information. it's just been -- it's been such fragmented and inaccurate data, or erroneous or something had been wrong with it. i'm not sure i'd buy --

>> it's incredibly frustrating to cover this for the families who are following this, because the information coming from the malaysian authorities has been all over the map, literally on this. and, you know, they said one thing yesterday, they took it back the next day. dave, you helped in the air france investigation, and we talked about this before. but the importance of trying to really, you know, get on one page in terms of what information you are releasing from malaysian authorities to, you know, say one thing yesterday, a new thing the day before, it just adds to the confusion in all of this. >> it sure does, anderson. and, you know, in the case of air france 447, the bea, their french equivalent of the ntsb, was very careful with what information got out there onto the streets. early on there was a lot of misinformation and speculation, but pretty soon it was focused on a couple of things, the last known position of the plane, the location of debris from that aircraft and then the

identification of some search area that we were going to begin searching in. but, you know, this is uncanny that the longer we seem to go, the more questions arise and the more difficult the job seems to be to locate that aircraft. >> fran, from an intelligence standpoint, you know, all these scenarios, are these all things that investigators themselves sit down around a table and kind of work out and try to basically just map out all the different scenarios and where those scenarios take them in terms of questions? >> that's right. for each scenario, what would you need to have happened, where could you find the space, the length of a runway, where would you -- where would you look for those clues. >> so people talk about speculation or scenarios, these are things that investigators themselves have to do to try to piece this together? >> absolutely. and they'll look at not only every passenger, every member of the ground crew, every engineer who touched that plane, and they'll look -- they'll try to

find relationships between them. are there any, whether they're social, professional. were there last-minute changes to the crew? were there last-minute additions or deletions in terms of cargo? what's the mechanical history of the plane? in a very detailed way. things is that the malaysians talked about going to the home of the pilots on march 9th but didn't say that they actually searched the home until the 15th. we're used to in the united states both the search and the investigation running in parallel. so to expedite it. and so they seem to have lost some time. and it may be that it has overwhelming for them to coordinate the search and rescue operation because of so many countries participating, but it is -- it's time that's lost to the investigators. >> and let's just -- a couple of obvious questions which people have been tweeting me all day or asking me, cell phones on board that flight during the flight, it was too high for any cell phones to actually be working. >> it's a 9/11 scenario that doesn't apply because those airplanes were very low comparatively.

you can't reach cell phone towers. if you do, you're picking up many towers. >> also for those who say, look, the pilot had a flight simulator at the house, do you know of a lot of pilots who have that? is that anything that raises any -- >> actually i know of a couple that -- i mean they enjoy having a busman's holiday. my wife and i own an airplane together. i still enjoy flying airplanes. yeah, he's got a simulator. maybe it's cost prohibitive for him to have an airplane over in malaysia. >> so that in and of itself doesn't raise questions? >> no. >> stick around, we'll talk to you in a minute. you can follow me on twitter @andersoncooper. any questions you have, let me know. we'll talk to a commander from the u.s. navy seventh fleet about changes in the search where the u.s. is looking now. they have very highly sophisticated information. we'll run through some of the scenarios that investigators have been looking at in a 777 simulator. it's pretty much -- pretty much 100% identical to the real thing.

and later investigating not just the captain and first officer, really the entire crew and the people on the ground to see if anyone, and the passengers, had a motive to any kind of foul play. when does your work end?

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soulmate is crazy. find your sleep number setting only at one of our 425 stores nationwide. you can afford a sleep number bed, you can't afford another mediocre night's sleep. know better sleep with sleep number. well, as we said at the top, the hunt for flight 370 covers millions of square miles in two directions, including a broad swath of south and central asia. commander marks is aboard the seventh fleet command ship and he joins us by phone. commander marks, the u.s. navy has made adjustments in how american assets are being used in the search. what can you tell us about where things are and where things go from here? >> our destroyer, the uss kid and helicopters has moved north, about as far north as you can get by the southern tip of burma there. essentially we have covered that entire area. we are pretty certain there is nothing there. and when you're looking at expanding into the rest of the indian ocean, and south, that is

such an incredibly huge area, using a destroyer really is our best asset. what we wanted to do was get our best asset able to be used the most, which is our p-3 and our p-8. what we're doing is sending a that's the p-8 poseidon, down to perth, australia. we'll have coverage out of the south out of australia and coverage to the north part of the indian ocean with our p-3. both of those will give us the best chance to search and find anything, much longer range than having a ship out there. so that's what we're doing, repositioning. just to give you a reminder of how their range is, they'll fly out 1,000, 1200 nautical miles and then have about four hours on station time to continue their search before having to come back so that's a big extension of our search area.

>> how much optimism do you and the crew have? i know obviously you're going to stay on the job until ordered otherwise. at some point, especially this far into the disappearance with no debris, is it frustrating? >> well, it's hard. the first 72 hours we consider that a search for survivors, and so obviously we're well past that now. but we think of it this way. for all this -- the families, every person on that plane had a family associated with them and friends associated with them. we know if it was us, we'd wanting the u.s. navy out here looking. >> are there enough assets in this region? i mean do you feel -- obviously there's a lot of countries involved in this. is it pretty well covered? do you feel like more assets would help? or was that almost diminishing returns? >> well, it depends how far south and into the indian ocean you look. i mean i can tell you the indian ocean goes so far, there probably isn't enough ships and

aircraft in the world to search every inch of it. if you take a map of the united states, superimpose that stretching from the north to the south indian ocean, it's kind of like saying, all right, i want to find a person somewhere between new york and california. i just don't know where they are. so that's the challenge here. >> it's extraordinary when you put it like that. commander marks, i appreciate you being on, thank you. good luck to all of you out there searching. thank you. and the search continues. unless you're a commercial airline pilot, it is hard to visualize what might have gone on inside the cockpit of flight 370. martin savidge is back inside a flight simulator to walk us through some of the details. richard quest also joins us, spent time with malaysia airlines before this incident. martin, you've been taking a closer look at the maintenance information system known by the acronym acars. tell us more about it. >> yeah, this is one of those

things that up until now the average flying public knew nothing about but of course any pilot at least on an aircraft like this would know. acars. think of it as an alternative way to communicate outside of the traditional radio systems. i can access it here if i look at this screen and pull it up. here i've got a simple menu. it's possible here to maneuver a mouse. a pilot could send a text message to the ground or the ground could send a text message to them. this is good when the aircraft is far out at sea and maybe radio communication can be spotty. another way to access the system, same acars, but this is a different backup unit, is to go in through this, what do i call this mitchell again? >> control display unit. >> control display unit. i hit this and you can see acars comes up. i punch this and i can get into the system this way. there's one here, one here, one here. that's three. with this there's four systems that are all part of acars. so four backups, if you will.

i can get into the menu and begin to shut things off. think of like your iphone where you turn off the wi-fi and maybe turn off the bluetooth, eventually maybe turn off the cellular. but that phone is still communicating even with that shutdown with the main telephone system. i can degrade the system. i can't shut it down. to do that, i've got to go somewhere into the electronics bay. i've got to be more of an electrical engineer. lastly, the transponder. we've heard a lot about that. this i can turn off very simply. one, two, three. it's off. we're now invisible to radar, at least identifying us from the ground. two main systems, but very different how you shut them down. >> martin, and maybe this is more of a question for your pilot there, mitchell, but why is it possible -- because i've gotten this question a lot from viewers. why is it possible to even shut down the transponder. why can pilots have that ability? >> the only reason that we have an off switch, anderson, is when

we're on the ground. after you're on the ground and land and taxi off the runway, you're no longer a factor for any traffic so there's no point in you being on the screen, you turn it off and save the air traffic controllers the hassle of trying to declutter the screen. >> but never in the air, only once on the ground and the flight is over. >> richard, the fact that the acars was not functioning, again, we don't know why, what does that tell you? >> what it tells me is that either it was disabled and degraded or something so dramatic happened that it -- that it literally cut it off. but here's the problem with that theory. a i can advance any theory forward and backwards, but eventually you can come back to the same problem. if there had been a fire or if something had failed on the plane or anything like that, the acars would have noticed it and would have reported it. that's the problem with the mechanical theory. it would have had to have been instant. it would have had to have

literally disabled -- a good question for the captain there, isn't that one of the issues, though, when we look at the mechanical problems that may have happened in the electronics bay or elsewhere on the aircraft, it would have had to have hit acars before acars could have reported it? >> yeah, absolutely right, richard. it would have to have been a catastrophic instantaneous failure because even if a few seconds went by where the acars system was able to communicate with the ground, it would have let them know something was happening. it would have had to have been a snap, boom, and it's over. >> mitchell, aren't there different -- just to confuse things all the more. aren't there different levels of acars that airlines can subscribe to and malaysia didn't subscribe to the more advanced one? am i correct in that? >> we talked about this, didn't we? >> that's right, we did. we talked about this. anderson, that's absolutely correct. some airlines -- actually most airlines in the world, malaysia

airlines is the only one that i know of that doesn't do this, subscribe to a system whereby the information that they send to satellites and vice versa is more robust. it's protected more and there's more information passed. you have to pay for that. it's like an iphone. again, 16 gigs, 32 gigs, 64 gigs. you want better performance, maybe a little faster, you upgrade to the 5s, get 64 gigs. you pay for it, but it's better performance and that's the same with the acars. >> so that would be coming back to haunt them now because they didn't have that more sophisticated data. >> if they did, it would have made the search a little easier because there would have been more information, perhaps easier to find and we would have found it by now. >> one of the important things is, if there had been a fire, if there had been something failing, acars would have reported this. we saw this in 447. the first indication of something wrong was 24 acars messages.

a light went on, acars told the ground. a flag came up on the pilot's display, acars told the ground. anything that happens in that cockpit where they are at the moment, martin, acars will tell the ground. >> so even though they weren't subscribing to the more advanced system -- >> oh, you're talking about a very basic level that would have told malaysian airlines there's a warning. >> and you bring up an interesting point, richard, which is no matter what theory that investigators go down, there's something that kind of ultimately brings you back. then you say, okay, if it was something catastrophic or something very fast that overwhelmed acars, then how come the plane was still flying around for hours if in fact the radar information is correct. >> and that's exactly the conundrum in this case. that's why as the minister said, this is no ordinary -- no normal investigation. this is why the ceo of malaysia airlines said this is unprecedented. this is why we're talking about

it at such great length because nobody can come up with a scenario that makes sense with the facts that we know so far. >> richard, it's good to have you on. martin savidge as well. i want to thank mitchell, our pilot, for your expertise. thank you. you can find out more at cnn.com. just ahead, investigators turned their focus as we mentioned before on the two pilots of the flight, the co-pilot, searching their homes, combing through their paths. we'll take a look at what they are looking for and what they have found, if anything, so far. hey guys! sorry we're late. did you run into traffic? no, just had to stop by the house to grab a few things. you stopped by the house? uh-huh. yea. alright, whenever you get your stuff, run upstairs, get cleaned up for dinner. you leave the house in good shape? yea. yea, of course. ♪ [ sportscaster talking on tv ] last-second field go-- yea, sure ya did. [ male announcer ] introducing at&t digital life. personalized home security and automation. get professionally monitored security for just $29.99 a month. with limited availability in select markets. ♪

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