Transcript of Press Conference, 9 April 2014
Angus Houston: Good Morning. I'm accompanied by the same team as on previous occasions, and I'm pleased to be here to brief you today.
Today I can report some further encouraging information regarding the search for missing flight MH370. On Monday I advised that the Towed Pinger Locator deployed by the Ocean Shield had detected signals consistent with those emitted by aircraft black boxes on two separate occasions. I can now tell you that Ocean Shield has been able to re-acquire the signals on two more occasion—late yesterday afternoon and late last night, Perth time.
The detection yesterday afternoon was held for approximately five minutes and 32 seconds. The detection late last night was held for approximately seven minutes. Ocean Shield has now detected four transmissions in the same broad area. Yesterday's signals will assist in better defining a reduced and much more manageable search area on the ocean floor. I believe we are searching in the right area, but we need to visually identify aircraft wreckage before we can confirm with certainty that this is the final resting place of MH370. For the sake of the 239 families, this is absolutely imperative.
Today the Ocean Shield is continuing the slow, painstaking and methodical work to refine the location around the four acoustic detections. We are not yet at the point of deploying the autonomous underwater vehicle. The better Ocean Shield can define the area, the easier it will be for the Autonomous Underwater Vehicle to subsequently search for aircraft wreckage.
It is important to note that Ocean Shield can search six times the amount of area with a Towed Pinger Locator than can be done with the sonar on the Autonomous Underwater Vehicle. Searching underwater is an extremely laborious task, so the more work we can do on the surface with the Towed Pinger Locator to fix the position of the transmission, the less work we will have to do below the surface, scouring the sea floor. Given the guaranteed shelf life of the pinger batteries is 30 day and it is now 33 days since the aircraft went missing, it is important that we gather as much information to fix the possible location of the aircraft while the pingers are still transmitting.
In further promising information, we have received the results of the data analysis conducted on the signals detected by Ocean Shield on the first two occasions. This data analysis was conducted by the Australian Joint Acoustic Analysis Centre based at HMAS Albatross in Nowra, NSW. It is the Australian Defence Force's centre of excellence for acoustic analysis.
The analysis determined that a very stable, distinct, and clear signal was detected at 33.331 kilohertz and that it consistently pulsed at a 1.106 second interval. They, therefore, assess that the transmission was not of natural origin and was likely sourced from specific electronic equipment. They believe the signals to be consistent with the specification and description of a Flight Data Recorder.
Up to 11 military aircraft, four civil aircraft, and up to 14 ships will assist in today's search. A modified RAAF AP-3C will coordinate with Ocean Shield in conducting a sonar buoy search in the same vicinity. Today a weak front is moving in from the south-east and is expected to bring scattered showers. The planned search area is about 75,000 square kilometres. You may have noticed the size of the search area has significantly reduced over the last couple of days.
Based on Ocean Shield's detections, we are now searching a much more concentrated area based on the drift predications made possible by Ocean Shield's detections. The smaller area has also allowed to us to plan much tighter search patterns, based entirely on visual search principles. In other words, we have intensified our search in the visual search area.
Just a bit of housekeeping. At my last press conference, I said I would come back to you with the precise timings of when the signals were detected by the Ocean Shield. The first detection took place on Saturday 5 April at 4:45pm, Perth time. The second detection took place on Saturday 5 April at 9:27pm, Perth time. The third detection took place on Tuesday 8 April at 4:27pm, Perth time. The fourth detection took place on Tuesday 8 April at 10:17pm, Perth time.
I'm now happy to take your questions, but before I do that, I would refer you to the diagram there which shows you where all the detections were made, and I would also highlight to you the satellite handshake calculation number seven. That was the handshake which was a partial ping, where the experts in Kuala Lumpur assess that the aircraft might have—plane engines might have flamed out, and it's probably significant in terms of the end of powered flight.
Question: Mr Houston, Will Ripley, CNN. What does your data show? Does it give you any indication how far the debris may have travelled from this particular area where the Ocean Shield is now searching?
Angus Houston: We have no idea of debris at this stage. We're continuing the visual search, a very intense visual search, in the hope of picking something up, because what we're dealing with the visual search is an area of search which has been adapted consistent with the amount of oceanic drift that has been at play during the period. Okay? So that's the first point. The second point is the only thing we've got at the moment in terms of this location here, is the detection of the transmissions.
We have no idea at this stage what is under the water, and of course, as soon as we finish the Towed Pinger Locator work, and hopefully we'll get some more transmissions to better refine the point on the ocean floor where the transmissions are emanating from, once we've got that, and there's probably no more hope of picking up anymore transmissions, we will put the Autonomous Underwater Vehicle down to have a look.
Now, hopefully, with lots of transmissions we'll have a tight, small area, and hopefully in a matter of days we will be able to find something on the bottom that might confirm that this is the last resting place of MH370. And I stress—and I can't stress enough—the families have to be considered when you report all of this, because they want a bit of certainty. We don't get certainty until we have a visual sighting of the wreckage. And that will probably come with the work the Autonomous Vehicle does.
The other thing about the bottom there, I'm informed, by experts, that there's a lot of silt down there. That could complicate the search because the silt on the bottom of the ocean can be very thick, and things disappear into it and it makes a visual search underwater very difficult.
Question: Mr Houston [indistinct] on Monday you thought that there was possibly two pinger returns. Do you still think you're dealing with two devices, or one at this point?
Angus Houston: Well, we've got the evidence, the assessment was made, that we thought there might be two pingers there. This has not been confirmed in the further detections that we picked up. Now, whether that's because, you know, one pinger has run out of battery life and there's one running, or we just haven't got close to it, I don't know. But the fact of the matter is we haven't had any further evidence of two pingers going off in the same area or at the same time.
Question: But isn't it curious that two pingers, the frequency was [indistinct] 33.3 on both of them?
Angus Houston: Well, I won't get into that, because, you know, basically the analysis on that I don't think has revealed anything unusual. I might ask Commodore Leavy if he has any further information on that?
Peter Leavy: No, we don't at this stage, Sir, no.
Angus Houston: No. Okay.
Question: Do you plan on moving more pinger locators into that area to cover more territory?
Angus Houston: Well, no we don't, because as I've said previously one of the important things about this sort of search is the need for complete—a completely noiseless environment. Ocean Shield is minimising all of its systems, and really, the only thing that is operating are the two thrusters at the back of the vessel. Everything else is turned off, so that we have the best search environment possible. If you had other ships there, you'd end up with a very noisy environment and you wouldn't get the sort of search that we've got at the moment.
I mean, this is—we are looking at this stage for transmissions that are probably weaker than they would have been early on because the batteries of both devices are passed their use-by date, and they will very shortly fail. So I think we're very fortunate in fact to get some transmissions on day 33.
Question: Is it possible that you could release a section of that audio recording so we could hear it?
Angus Houston: We'll take a look at that. I don't see why not.
Question: Technically, how many detections do you think the Ocean Shield needs to refine the location eventually, because now you already have four detections and you say you still need more detections to refine the location? And second, do you have more information regarding the detection received by the Chinese ship and do you still think it's a reliable one?
Angus Houston: Well, in terms of Ocean Shield the more detections we get, the better and the other thing that comes into it is the quality of the transmission and the detection. What we're after is the best return that we can get from the deep and by triangulating all of this positional data, we will be able to come up with a much more sharply defined search area, a much smaller search area underwater. Bear in mind, that the time spent on the surface we're covering six times more area at any given time than we'll be able to do when we go underwater.
So with the batteries likely to fade or fail very shortly, we need to get as much positional data as we can so that we can define a very small search area. Bear in mind, with the Air France disaster several years ago, it took them 20 days. They had a very good—they thought they had a good fix and it took the underwater vehicle 20 days to get to the wreckage.
Question: Air Chief Marshal, accepting what you say that the Ocean Shield needs to work in silence over this—as I understand it, moves across the area. During that period when it's passing over is it worthwhile at all to send a manned submarine to have a look at what's down there and have you considered that?
Angus Houston: Well, I'm not running the search. We've got the Australian Maritime Safety Authority running and coordinating the operational search and, of course, the Defence Force are providing a lot of the assets along with many other nations. There's a lot of military assets out there at the moment. And, of course, there is one submarine. I might just get Commodore Leavy to just comment on that particular aspect of your question.
Peter Leavy: The short answer is the utility of submarines has been evaluated and it was—when we first started commencing this search, and it was determined that the Collins class submarine would not be optimised for this search. What we do have today, as Air Chief Marshal Houston just mentioned, is a RAAF—A Royal Australian Air Force P-3 aircraft deploying a series of sonar buoys in the field. That does provide more sensors in the vicinity of Ocean Shield without having a ship there to produce the background noise.
The way that will work is an acoustic processor in the aircraft has been modified, some very good work that was only started after the MH370 aircraft was lost, some very good work by the Australian Defence Force and in particular the Air Force, have modified the acoustic processor to be able to pick up the 37.5 kilohertz frequency and we expect any time now the aircraft, the first aircraft out with Ocean Shield will be coordinating with her to lay a sonar buoy pattern. Sonar buoys essentially a sensor package that's parachuted out of the aircraft, floats on the surface of the ocean and will deploy a hydrophone 1000 feet below the surface of the ocean and a sonar buoy that floats has a radio in it that transmits the data back to the aircraft.
Each P-3 is capable of carrying 84 sonar buoys on each mission and so that will provide a sensor, a range of sensors, a number of sensors at least 1000 feet below the surface. The Towed Pinger Locator is obviously much deeper than that but at least it does provide a range of sensors 1000 feet down which are 1000 feet closer to the possible source of the pinger locator beacon on the ocean floor.
The other point I would make is—and Angus Houston mentioned this—is the silt cover on the bottom as well as potentially hiding the debris. Now that we have an analysis that shows there is silt down there, that's quite an absorbing material so we are at risk of a lot of the sound energy being absorbed by the silt rather than if for instance it was a rock sea bed, a lot of that would be reflected back up to the surface or towards the surface. So the fact that there's silt there has also hindered, to a certain extent, the sound path propagation.
Question: Have you got any further information from the Chinese ship Haixun 01 and have you analysed the data acquired by that ship?
Angus Houston: I understand there has been no further detections in the area where the Chinese vessel Haixun 01 assisted by HMS Echo, which is an oceanographic vessel from the Royal Navy, I believe they haven't made any further detections. In terms of the analysis of the signals that it picked up, I'll come back to you on that. I'm not sure where we're at with that. I haven't had any advice that the analysis is completed at this stage.
Question: Will you begin the search and looking at the odds, the size of the ocean, the size of the search area, what do you think the chances were that you'd be making an announcement like this today?
Angus Houston: Well, I would say very quickly, caution again, what we're picking up is a great lead, okay? We've got to visually acquire before we can say this is the final resting place, so there's still a way to go. But if you had asked me let's say when I arrived last Sunday night, I would have been probably more pessimistic than I am now. I'm now optimistic that we will find the aircraft, or what is left of the aircraft in the not too distant future. But we haven't found it yet because this is a very challenging business. We're relying on transmissions that have come and gone and I'd just like to have that hard evidence, a photograph, evidence that there's pieces of aircraft down there to know that actually this is the final resting place of MH370.
Question: Based on this diagram here, would it be better to say that you're now looking in a diameter of 30 kilometres, 25 kilometres, something like that?
Angus Houston: You can see the scale on the bottom. The scale on the bottom, that's on the left, 0, 10, 20 kilometres, and you can see it is a relatively small area. And again, I…
Question: But are you're confident you've narrowed it down to say 25 kilometres or…?
Angus Houston: Well, I'm confident that we've got an area there which provides a promising area to exploit. Note, the satellite handshake calculation and ping seven. That's another source of evidence. So, I think that we're looking in the right area, but I'm not prepared to confirm anything until such time as somebody lays eyes on the wreckage.
Question: [Indistinct] for the sake of the families, for the sake of precision, but we are looking at a case where we've got frequencies which are consistent with a black box that have been verified by the black box manufacturers, by acoustic analysis, they have been consistent, they've been sustained, and they are where the science suggests the plane is. Can you give a percentage, without holding you to it, 80 per cent, 90 per cent, how confident are you? I understand you have to express caution, but how confident are you?
Angus Houston: I have confidence we're in the right area, but I'm not going to give the final confirmation until somebody has seen wreckage, okay? And I'm not prepared to go this percentage or that percentage.
Question: Chief Houston, you said you want to wait to get some more transmission from Ocean Shield, so for how many days do you want to keep the locator working before you deploy the remaining…?
Angus Houston: Well, the reason we want to do that is that there's no second chances. It looks like the signals we've picked up recently have been much weaker than the original signals we picked up. So that means probably we're either a long way away from it, or in my view more likely, the batteries are starting to fade and as a consequence, the signal is becoming weaker. So we need to, as we say in Australia, make hay while the sun shines. We need to get all the data we can, because by getting more data we will be able to compress this area into a much smaller area where we do the very difficult and very challenging search with the Autonomous Underwater Vehicle.
Bear in mind we've heard about the silt, the silt on the bottom will complicate that search and sometimes silt can be tens of metres thick. It's a very difficult environment, so the more effort we put into the location of where the transmission is coming from, the more certainty we will have that we will find something on the bottom of the ocean.
Question: What are the other vessels working on, like [indistinct] and HMAS Success, what are they doing physically in the search area?
Angus Houston: Well, what we're doing, we are not putting all our eggs in one basket, okay? We're continuing with all the other activities. We're continuing to look where Haixun 01 is, but we're also doing a much more intense visual search, a visual search where the track spacing, if you understand that, what an aircraft does, it's assigned an area to search and then it will design a pattern with very small spacing and it will cover the area very extensively and very intensively.
That's what's happening now in the area where we think wreckage from this area here would have moved with the ocean drift, the currents and the waves and so on. We are now searching the area where after 33 days the scientists, the analysts assess where the wreckage might be now. And we hope that we'll also find something on the surface of the ocean which confirms that the aircraft basically entered the water at this location.
Question: [Indistinct] you won't have any choice than using your submarines' tools? You should not find anything more; are you going to use your submarines?
Angus Houston: Well, you know, submarines have their limitations too, particularly in terms of—they have a limitation in how deep they can dive. And of course that's a very classified area. All nations, they don't declare how deep their submarines can go. The environment down here is around, we've said previously, 4500 metres, so what we're talking about are specialist Underwater Autonomous Vehicles and specialist other vehicles that could be used for recovery. So, this is the domain in which you use those sorts of vehicles. So, from here we will be looking further downstream for other vehicles that might be able to operate in the environment if we find, if we find obviously the aircraft. Just one at a time. You first and then you.
Question: The distance between the points here on this map is about let's say 25 metres maximum. In the past we were told that the detector could only really pick up sounds about a mile away from the black box locator beacon. Are you reassessing the physics of how these sounds travel underwater at this point because you're detecting things which are much further apart than that?
Angus Houston: No, well, again, you heard the Commodore say the bottom is a silt bottom, that absorbs sound and funny things happen, depending on temperature, temperature layers and so on and so forth. So, the characteristics of the water, the characteristics of the ocean floor all come into play here. Now, the other thing is that in terms of this area, the Ocean Shield went there on 5 April. It deployed the Towed Pinger Locator and it has been pulling that Towed Pinger Locator since then. So that's—what, that's four, five days. And it has searched that area continuously through that period of time. This is what we've picked up at the moment and you will note that the most recent detections are all down in the southern part of the area.
Question: What was the depth of the TPL on Tuesday when those two signals were acquired?
Angus Houston: Away you go.
Peter Leavy: Okay. It was around 1000 metres above the seabed. So around 3500—fully deployed.
Question: Given that that does look about 30 kilometres apart, is that—do the experts say that's consistent with what could happen on the plane's impact and the distances between the locations and furthermore, I wonder if the Commodore can comment on whether there's a strong drift at the bottom of the ocean which could disperse things.
Angus Houston: I think you will handle all of that, you're the Naval Officer.
Peter Leavy: It's quite possible that there is currents down there which could have disturbed the debris and also as it was falling from the surface it would have dispersed over a fairly large area as well. It has been said we know more about the surface of the moon than our own seabed of our ocean floor. I think that's probably right. So we don't have accurate sampling of the currents in that particular area. The indication we have that silt is on the seabed is taken from some core samples that were taken some years ago and 130 miles away from our current position by an oceanographic ship that are in a database that we can access. But that gives an indication of how little understanding we have of the detailed topography of the seabed. But the concept of having water movements and flows down there is one we need to take into account.
Angus Houston: Up at the back. Sorry, I've [indistinct].
Question: I'm sure the families must take some encouragement from what you've announced today but as you say, that confirmation must be visual from the autonomous sub. What is your best understanding of when that sub could go down. Do you have a time frame in mind; one, two, five, 10, 20 days? When you make…
Angus Houston: You mean the Autonomous Underwater Vehicle?
Angus Houston: We will send it down when we've exhausted the possibilities in terms of the surface search. This is a personal opinion, I don't think that time is very far away at all because I think the last signal we got was a very weak signal. If we continue to get signals though, we will continue to search for the very simple reason that the underwater vehicle, it operates at walking pace, okay. It has a relatively narrow swathe and it takes days and days and days to cover even an area like this. In fact, this area you see here would take it—we'd be talking in terms of weeks, not just days.
So, the more time we spend getting the locational data, the better off we're going to be when we come to the underwater search and remember what I said in my brief, essentially it takes six times longer to cover the same area with the underwater submersible as it does with the Towed Pinger on the surface.
Question: If maybe I could ask another way. How long will you wait from the last ping you receive or the last signal you receive, which, as you said, was last night, if you hear nothing more how many hours or days will you wait before deploying the autonomous vehicle?
Angus Houston: Well, I think those judgements have yet to be made. This is a very dynamic process and judgements are made on the basis of a lot of factors and clearly we are not at that point yet. So, I can't give you any information at this time. I would imagine though it's not far away before we deploy something to go down and have a look.
Question: Mr Houston, there were reports that debris was found and which was sent for investigation, is there any update on that?
Angus Houston: None of the debris we found thus far has had a connection to MH370. But we're now in a search area and we're working very intensely and we're hopeful, we're hopeful that we might find something that has a connection to the aircraft. So, we'll just have to wait and see how that goes and if we find anything of significance we'll obviously let the media know.
Question: This more intense search area, have you already been over that before in a broader pattern?
Angus Houston: I think we've probably been over on a broader pattern but we haven't done it the way we're doing it now. You might remember over the last week we've been covering areas of 220,000 kilometres, areas the size of Ireland or one of the largest provinces in China. We're now sending the same number of aircraft out to a search area which is much smaller. Consequently, we can do a much more intense, a much more thorough search, visual search. Before we were doing, if you like, an all sensor type search using radar and eyes. But what we're focused on right now is a visual search, a visual range. I think the track spacing is usually about two miles each side. And I think that's visual search 101.
Question: How big is the new search area exactly?
Angus Houston: Sorry?
Question: How big is it exactly, where you found the new ones?
Angus Houston: We are searching 75,000 square kilometres.
Question: Given the debris that was spotted previously had nothing to do—you believe with MH370. Is there any chance that the frequencies actually have nothing to do with the transmission devices that you're looking for? You said they match up the frequencies, but you don't believe them to be are there anything natural but are there any other possibilities being spoken about that they could be something unrelated?
Angus Houston: Well, we think—well, we've had the analysis done. It's nothing natural, it comes from a man-made device and it's consistent with the locator on a black box. So that's why we are more confident than we were before but we've got to lay eyes on it. Okay. One more question.
Question: Are you concerned the family members if they come to Perth that there's not enough accommodation for so many people that come here at one time?
Angus Houston: We are working—that's one of my roles to coordinate that. This week is very busy in Perth because there's a big conference. That is true right now but we have thousands of people here at the moment, thousands of visitors. From the end of this week we will have adequate accommodation to cater for the families and we will be keeping a very close eye on that. We are working very closely with the Chinese Ambassador and his staff, the Malaysian High Commissioner and his staff, Malaysia Airlines and the West Australian Government, the city of Perth and the city of Fremantle to ensure that we can do everything possible to ensure that the families are looked after and taken care of when they come to Australia.
We want them to—we know it's a very sad time for them but when they come they will be looked after. And we are very focused on that and I must say the West Australian Government, the Federal Government are both—see this as a very, very high priority. Thank you very much.