MH370 Search Briefing Q & A: April 7

Question: [Indistinct] assume that if the black box batteries were to die in the next day or so, do you feel that we’re now close enough that you would be able to effectively find the wreckage of the plane if it is indeed there?

Angus Houston: I think that the lead we’ve got at the moment justifies a very thorough prosecution. Obviously, we’re doing—the first thing we’re doing is trying to fix the position on the basis of the return transmissions that were picked up earlier on. Hopefully, we will re-acquire those transmissions. But you’re right. The life of the batteries must be getting somewhere close to the end of life. It’s, what, 31 days? So we’re already one day past the advertised shelf life. We hope that it keeps going for a little bit longer.

But then we need to go down first of all with the Autonomous Underwater Vehicle to map the ocean floor. The subject matter expertise that is available will be able to determine if there’s something unusual on the sea floor like aircraft wreckage, and in the event of finding something unusual, the Autonomous Underwater Vehicle will come back to the surface and will then be fitted with a camera, and hopefully we would then be able to pick up imagery.

Now, I stress, this is very deep water—4500 metres, and the limitation on depth in terms of this vehicle is 4500 metres. So we’re right on the edge of capability, and we might be limited by the capability if, for example, the aircraft ended up in deeper water.

Question: Two questions. One, is that possible that the signal detected by the Ocean Shield and the Chinese ship are different, you know, belong to different black box, the one belonging to the Flight Detail Recorder, and the other one belonging to the Cockpit Voice Recorder? And then one question is, what’s the moment, we want to know—what’s the moment for official confirming that [indistinct] signal, you know, consistent or inconsistent with [indistinct]. It must be followed, that critical [indistinct]?

Angus Houston: In terms of both of those events, they’re in the area of probability that was worked out by the experts in Kuala Lumpur. So we have to prosecute both contacts. We don’t know at the moment; we don’t have any confirmation that one or the other is significant enough for us to say yes, this is where the aircraft is. We have to have further confirmation. And I would put it to you that we cannot confirm it until we have found some wreckage. And that’s why the work that the Bluefin 21—the work that it does—is absolutely vital in the immediate future. And of course, we need a good position on the ocean floor to be able to prosecute a quick and efficient search. If we’re dealing with an imprecise position, it’s going to take a lot longer because we’ll have to search a much larger area.

Question: Mr Houston, can you please clarify the timeline of the most recent detections by Ocean Shield? Exactly when those two pings were detected and also is it possible that the series of different pings by Ocean Shield versus the series of detections by the Chinese, could they be from the same signal or are they definitely different events or one or the other [indistinct]?

Angus Houston: Well, the two events—that search area is over 300 nautical miles long. One was at one extremity, the other at the other extremity so I would say unlikely that they’re the same event. But in deep water funny things happen with acoustic signals particularly with different temperatures, layering and so on. And I might get—I might actually get Commodore Leavy to speak about that in a moment. In terms of the timeframe, you might—I don’t think you were here yesterday—but I referred to the fact that just before the press conference, we were starting to hear that Ocean Shield had made a contact but we had no detail at that stage. And over the last 24 hours and, indeed, for probably the next 24 hours, Ocean Shield will continue its runs back and forth over the area. I might add this is a very time-intensive operation because it’s towing a lot of cable and to turn it round to come back again takes three hours to turn around.

Question: Were the detections 24 hours [indistinct]?

Angus Houston: Well, more—well, the detections as I understand it, the first detections were around the middle of the night, not last night, night before.

Question: And then how many frequencies…?

Angus Houston: There’s been two contacts thus far and they were early on in the process and the precise timings I haven’t got for you but one of those contacts was for two hours and 20 minutes. The other contact happened on the second run so we can get the precise time for you but it was I would suggest it’s probably several hours later, given that it takes three hours to turn the whole set-up round. And the other question you had—is that—I’ve answered it, great.

Angus Houston: In terms of locating this pinger, I mean how big of an area—I mean how precise are you able to locate that area at this point? Is it within a couple of miles or is it a hundred miles or…?

Angus Houston: What I might do is ask the—one of the subject matter experts, Commodore Leavy to address your question and you might just add a little bit on some of the challenges associated with the work that’s being done underwater. Peter.

Peter Leavy: I might just open with some of the challenges we face. As you’ve heard, most of the—all of the detections that are happening at the moment are acoustic, you can think of it essentially as deployed microphones listening for sound and on the Towed Pinger Locater, that’s sitting approximately 3000 metres below the surface of the ocean. Unlike in air where sound travels in a straight line, acoustic energy, sound, through the water is greatly affected by temperature, pressure and salinity. And that has the effect of attenuating, bending, sometimes through 90 degrees, sound waves. So it is quite possible and very hard to predict—it’s quite possible for sound to travel great distances laterally but be very difficult to hear near the surface of the ocean for instance.

So it is a markedly different environment to what you see with sound travelling through air. And it’s a very specialised skill set that is being employed at the moment. In terms of the Towed Pinger Locater, we’re expecting around a 2000 yard detection range. So, you can picture now, moving three knots through the water or five kilometres an hour, with a detection range of around two miles. That’s a very small piece of area that’s being searched. Ocean Shield at the moment is on her fifth leg of a search that’s an expanding square around that initial detection point.

That will take—or she will continue on that profile for another 24 hours. If they gain another acoustic event on that Towed Pinger Locater, that will be the trigger at the moment to launch the Autonomous Underwater Vehicle with a more accurate sonar and potentially, a camera for mapping and visually looking at the ocean floor. But at the moment that’s not deployed. The focus is on trying to re-acquire the acoustic signal that they had 24 hours ago. In terms of area, by the end of tomorrow when they’ve completed their runs, they expect to have a three by three mile box searched. So, it is quite a small area that will be searched very thoroughly but it is a very small area and it gives, I hope, some sense of the challenges that they’re facing out there.

Keep in mind each of the runs that they conduct, is around seven miles long with the turn at the end and it takes quite some time—around seven to eight hours to do each leg and to do the turn at the end. They need to steady on the new course and allow the Towed Pinger Locator to complete the turn and settle down so it is a very, very slow and painstaking process. We have the best in the world out there doing it though. So, we’re confident that if there is—the pinger out there and it’s still radiating, we’re quite confident that we should find it. We’ve got the best in the world engaged in this task. Thanks, Sir.

Angus Houston: Thank you very much.

Question: I’m not sure who’s best to answer this but when we’re talking about acoustic signals, the frequency, the signal emitted by a black box, what else could it be at that frequency?

Angus Houston: Well, I think we just have to be very, very careful because we need to confirm it in my view with imagery of wreckage. I…

Question: Is there anything in the natural world that emits…?

Angus Houston: I don’t—my view is, my personal view is, probably not but as you’ve just heard, strange things do happen in the ocean and I would want more confirmation before we say this is it. The point is that this correlates very well with the work that was done in Kuala Lumpur and essentially, this has been done without finding any wreckage thus far. And I think it’s quite extraordinary and what I’d like to see now is us find some wreckage because that will basically help solve the mystery. And I would ask you to respect that because fundamentally, without wreckage we can’t say it’s definitely here. We’ve got to go and have a look and hopefully we’ll find it somewhere in the area that we’ve narrowed it to.

Question: How optimistic are you at this point?

Angus Houston: Well, I’m much more optimistic than I was a week ago and some of you saw me a week ago. I was really concerned because we hadn’t found any wreckage which is usually I think in most other searches of this nature, the narrowing of the search area and the eventual finding of the downed aircraft has been enabled by wreckage on the surface.

Question: This might be [Indistinct]…

Angus Houston: Just wait a minute. And essentially this to my knowledge right in the middle of the ocean, this is quite an extraordinary set of circumstances that we’re now in a very well defined search area which hopefully will eventually yield the information that we need to say, MH370 might have entered the water just here.

Question: [Indistinct].

Angus Houston: Yeah.

Question: I think you said there were two distinct pings [inaudible] potentially from the flight data recorder [inaudible]…

Angus Houston: Yeah.

Question: Did you get a sense of how far apart those two detections [indistinct]?

Angus Houston: I will get the subject matter expert to have a word. I’ve heard the—what we’ve got is, we’ve got a visual indication on a screen and we’ve also got an audible signal and the audible signal sounds to me just like an emergency locator beacon and what we’re talking about, there were two separate pingers so what we’re probably looking at on the second run, is the fact that we probably had not only the main emergency locator beacon but also the Cockpit Voice Recorder. If that’s—that’s the sort of signals we were getting. Do you want to say any more on that?

Peter Leavy: Thanks, Sir. My understanding is they were around 2000 yards, just under 2000 yards apart. Of note, the first detection was made whilst the Towed Pinger Locator had been retracted so, it was much shallower. The reason they do that is at the end of each turn, as the ship turns around, Ocean Shield reverses course, if they don’t retract the Towed Pinger, the effect of movement through the water slows down—the pinger will sink because the effective ship movement is reduced. So, they—it’s brought up close to the surface. That also helps speed up the turn and once they’re around it’s then deployed fully again. So, the first detection was obtained whilst the Towed Pinger Locator was at a relatively shallow depth and given that it’s within about 1800 yards to 2000 yards, the two detections, that would be consistent with the sound anomalies that I mentioned before, the different propagation parts. So, it’s quite possible that even though they assess it to be within—around 1800 yards apart, it’s quite possible that it could actually be from the same source on the seabed.

Question: In case you are unable to [indistinct] the signalling, what would be your next course of action?

Angus Houston: Well, we’re very focused at the moment on exhausting the investigation into that source and that’s going to take quite some considerable period of time. For example, for the rest of the day, I would imagine and probably into tomorrow, we will still be doing Towed Pinger runs over this area. Now, when that’s finished, probably the next thing would be to—let’s say if we find—we’re able to fix the location, we will send the Autonomous Underwater Vehicle straight down. If we’re unable to fix the location, the people who are out there have to do an analysis of everything they’ve got and make an assessment as to whether they would deploy the underwater vehicle to go down and have a look in the most likely area. So, I would anticipate that’s what will happen, the underwater vehicle will be deployed and we’ll continue the work.

And just to emphasise again, if we have a large area of uncertainty, it will take several days to actually cover a fairly—what would appear to be a fairly small area, things happen very slowly at the depths that we’re dealing with. Do you want to say anymore about that; I think that covers it.

Question: Does the area that they’re looking to search, are there any waters that are deeper than 4500 metres?

Angus Houston: Absolutely. We are dealing with very deep water, some of the water out there exceeds 5000 metres which is going to be very challenging and very demanding and we will need other vehicles to go down there to that depth.

Sorry, could we—this gentleman here first please.

Question: [Indistinct] use for information by the ship search, does it mean you will review the aircraft search and rescue operation?

Angus Houston: No, not at all. Not at all, because I mentioned the need to find wreckage. We have not seen any wreckage at all yet and I think in previous incidents, accidents, involving aircraft over the water, sometimes quite a big piece of wreckage is found in the water. Witness what happened with the Air France disaster a few years ago. The only large piece of wreckage that was found on the surface was actually the tail so, I think we need to continue the search and again I emphasise, this is not the end of the search. We’ve still got a lot of difficult, painstaking work to do to confirm that this is indeed where the aircraft entered the water. I would not be prepared to confirm that this is the spot where the aircraft is at the present—on the present evidence. We need more evidence and the best evidence we could find, is imagery from the autonomous vehicle that suggests the wreckage is on the bottom of the ocean and a photograph that demonstrates that and we can then say, this is where the aircraft entered the water and the wreckage is on the floor of the ocean.

Question: If you find that wreckage on the floor of the ocean, what would be the next step?

Angus Houston: Well, we then go into the recovery operation and the recovery operation as we saw with the Air France circumstances will take a long, long time and just depending on the circumstances, I’m not prepared to speculate about that. We would need to—the starting point will be to sort of map where wreckage is and all the rest of it and that will take a period of time and that will be the vital starting point for whatever unfolds after that. But it’s very deep water, very difficult—I guess, I was involved as Chief of the Defence Force with the recovery of a helicopter off the coast of Fiji. We knew exactly where the helicopter went into the water and it took us a long, long time to recover the Blackhawk and the person who was inside it. So, I just emphasise nothing will happen quickly, we’re talking about a long operation here which will be measured in months and we have yet to find the aircraft. Okay. One more question and I’ll take it over here.

Question: [Indistinct] white floating objects?

Angus Houston: Yes, yes. Apparently they’ve been checked out and they had no relationship to MH370. Ladies and Gentlemen, thank you very much for coming today and I’m sorry, we could be here all day—thank you very much for coming along and again, I stress, we need to think about the families here. We have a promising lead but we have yet to get the confirming evidence and that will be a long process. But we have been as open as we can be with you. We’re hiding nothing and that’s the circumstances as they stand right now.

Thank you very much.

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