Perhaps, but will it be Robust and Sustainable to be Fit For Purpose?

IF the GSF Explorer is enroute, it is what is underneath that counts...

http://i60.tinypic.com/kq8t0.jpg

What is your source? All the tracking sites show her in India as of 4/4.

Looks like the Ocean Shield just made a pass over one of the older ping-heard locations.

http://i1155.photobucket.com/albums/...psc88ddda7.jpg

CVR/FDR dumps
 

Real-time data streaming for all flights seems a bit ott. The question, then, is when to stream? High priority ecam messages, distress squawks and manual triggers (stand-alone and linked to actions such as arming fire bottles) would be possible trigger points. Probably as good as any, really. Like any other system, it has to be possible to power down the satcom in case of fire or fault, and a well-read hijacker would know to do this, but it would be potentially life-saving if engineering people at home or at Boeing could see just what was happening.

It may not have the original equipment for the task since it got refitted for drilling in 1997 according to wikipedia

Perhaps I was not clear enough. There is no need to transmit all this data all the time. The idea is not to replace black box, but to regularly transmit only very small subset of its data, so that the plane can at least be found. Basically, it should transmit only what is necessary, and only when it become necessary. Intelligent device must periodically send just GPS position and basic flight information in small and highly compressed single packet, using cheap, low bandwidth link. Having all relevant data at its input, it would always be aware of severity of any fault status or warning, and it would only then transmit more data, if necessary opening more expensive higher capacity link. In most dangerous situations, it would open emergency, reserved, highest capacity satellite link, and in a very short time upload every single bit of highly compressed data at its disposal. That could be much more than any current black box could hold. On average it would require, for example, just 1 KB of data by lowest capacity link every 10 minutes, so extra price would be very small, and we would still immediately have all the content of black boxes in all detectable emergencies. Traditional black boxes would still be there in case of communication problems.

On demand would be better, an aircraft goes missing dial into the box via satcom and retrieve the data or listen/watch live.

Of course this wont work if all systems are disabled.

that central area where OS is in the diagram & north, and HMAS Echo ran a parallel sweep, must be the area of greatest interest. That was where the strongest signals were detected.

It seems like a system that mirrors Amateur radio's packet networks might be beneficial in transmitting airliner's positional information without the need for satellites. Over most of the globe an airliner in flight is at least line of sight with another airliner that can act as a digital repeater of sorts, transmitting positional data to another airliner, or to a ground station if nearby.

https://en.wikipedia.org/wiki/Packet_radio

Although its not the fastest way to go about this task, it is dependable. If installed in every airliner the system would be nearly flawless, as each plane's position would be present on several other aircraft's memories, local to it.

There is no logical reason why this task must be relegated to the mainframe/dumb terminal way of thinking.

The Malaysian authorities have finally determined that the final words from MH370 were spoken by the pilot. Has it been determined whether all the communications between MH370 and ATC were spoken by the pilot? If so, then there’s nothing new. But if some of the earlier communications were spoken by the co-pilot, then it would be interesting to find out which ones, and when the change occurred.

I'm not so sure about the networks absorbing the bandwidth system wide for all aircraft in the air. Maybe it can.

I did look up some numbers. Data charges are in the $7 to $25 range. So assume 25MB per hour, looking at $175/hr. Maybe you can undersample, can limit the parameters. So call it $50 to $100/hr. That is just FDR; CVR is going to be a couple of voice channels at say $30/hour each.

Maybe that is enough said on this topic, but all in all, how much extra sim time per year could you give each pilot for that money?

Transmitted to where, that is the question. Over the sea, it would have to be satellite and bandwidth on satellites is a scarce resource and is costly.

Would a satcom person please step in? The raw bandwidth of a sat link is misleading. Individual A/C must either be polled (asked to transmit) or must speak up in the hope that data can be communicated. Simultaneous asychronous speakups - "collisions" - jam things up and the various originators must be separated in time, so they all get their data packets through. Because of transit time to/from the satellite(s), there is considerable latency involved, and at peak traffic times, actual throughput can be reduced to a fraction of the raw capacity of the sat channel. A small fraction.

This was covered extensively in the AF447 saga, and should be summarized here and "stickified" to reduce misconceptions. At least for the few that will read it before posing novice questions or "solutions".

Satcom and all that stuff
 

Several recent posts have raised questions regarding satcom capacity and the possibility of packet data relay systems between aircraft to carry aircraft position information. These are valid technical questions but seem to be putting the cart before horse.

The real questions do not at this stage cover "how" but should concentrate on what it is that we are trying to achieve. Currently aircraft position information is available either on a schedule or on request by ATC using ADS and CPDLC. This information uses ACARS and is carried on VHF or satcom as is appropriate. ACARS is used primarily because the only global data network on the ground throughout much of the world is the airline data communications networks operated by ARINC and SITA and ATC units are connected to these.

This system could be extended to carry FDR data but to whom? Where would it be stored? Once these questions are answered then it will be time to start looking at the airground links to be used.

As a former colleague with a military background used to say, "Strategy is about what needs to happen; when the word 'HOW' crops up you are getting into tactics."

Let's get the big picture right before we drop down to the bit level.

SS searching?
 

There was a stretch yesterday (within the past 16 hours) when neither Ocean Shield nor Echo were in the "box". Perhaps they were standing off while one of those which do not say where they are going nor where they have been was having a listen.

More likely standing off while they dropped the sonobuoys. Wouldn't want to get tangled up in the 1000 foot cables suspending the hydrophones.

Airbubba - Things are a bit different on the 777

VOICE RECORDER Switch

AUTO – The cockpit voice recorder runs from first engine start until 5 minutes after last engine shutdown (spring–loaded).

ON – The cockpit voice recorder runs until first engine start, then spring–loaded to AUTO.

No CVR circuit breaker in the 777 cockpit. The circuit breaker is in the E/E compartment.

Prop duffer
 

I'm not a supporter of the Malaysian govt. However, I cannot think of a similar precedent involving Malaysia where the eyes of the international community have been focused to such an extent on them.

There are powerful people here demanding and needing answers, from Boeing and Rolls Royce onwards. An enormous number of nations have become involved in the SAR and in checking and supplying other data towards the investigation. We don't know exactly who knows what but we do know there are numerous undisclosed assets operated by various nations and parties who already know more than we do about what is going on.

I'm believing it will not be in their interests to come up with a complete whitewash. Many epithets may be thrown around such as bumbling, inept, slow-on-the-uptake etc.

But if I'm wrong, I'll be happy to come back here and apologise, and will throw my hat into the cynics ring of all things Asian.

It seems the marinetraffic web site has removed the Ocean Shield and Echo track and position histories. The "current" position and speed is still there but I can't get the tracks or histories to show up for the last 3 or 4 hours. I'd been saving them for the last several days.

Hopefully it's some kind of weekend maintenance and not a move to keep the public from seeing the action.

@VinRogue
Unfortunately this won't help a whole lot. The ULB is a very simple, low power piece of equipment. The key to the low power consumption is due to its simplicity. To incorporate a transpond functionality requires a detector to run on the ULB. So lets crunch some theoretical numbers.

The ULB pingers output at a level of 160 dB re 1uPa. That is equivalent acoustic energy of 0.075W, or 75mW. Assuming inefficiencies in amplification require a 10x amount of electrical power to produce that amount of acoustic power that gives us 0.75W.


The ping is 10ms long, thus the ENERGY per ping is 0.75*0.01 = 0.0075joules or 7.5mJ.


At a rate of 1 per second, gives an effective average power requirement (ignoring circuitry – which should be pretty simple for a dumb pinger) of 7.5mW.


Now, the company I work for makes underwater acoustic communications equipment. An example of a simple, high efficiency FSK detector uses approximately 77 milliwatts when running in continuous detect mode. That is 10x my estimated consumption for the simple pinger. An that is without the power requirement to generate an acoustic signal in response.



So not a practical option with the current ULB form factor.

Side-scan Sonar
 

Maybe someone can post the tracks but it looks if HMS Echo is doing a side-scan sonar run each time ADV Ocean Shield does a slow turn.

I wonder if it really makes sense to continue committing so much manpower, and materiel, to the visual search that's taking place >500 km to the West of the underwater search area. The chances of finding debris on the open ocean after almost 40 days must be tiny. Moreover, even on the off-chance that some debris is found, it would now be much too far from its point of origin to help narrow the underwater search area any further.

As per a report in the ET
 

their summary of the search in a slide show

Flight MH370: Search teams receive signals again - Flight MH370: Search teams receive signals again | The Economic Times

Finding some debris may help those still clinging to a desperate hope that their loved ones are still alive, to come to accept that this is not the case.

ve7pnl's list of recommendations (11 April 21:27) gave me absolutely the biggest laugh I've had for months. :ok:

Through the streaming tears of laughter I'm sure many of us would see the truth of his serious underlying point.

The AIS data is quite sparse - sometimes 7 hours between individual tracking points:
Ocean Shield
Echo
Even the highest cost AIS membership only gives 12 hour tracking interval.
You can click on the vessel icon then "Show vessel track" to see last 9 locations mapped.

So a lot of the true track is hidden - one has to infer from speed & course.
Also the TPL is well separated from Ocean Shield. Echo is staying well back from the TPL when it is running.

The current interest seems to be near depths of 5,000m - 5,500m between -20.95 to -20.85 lat. and 103.9 to 104 lon.. That may account for suggestions this may be a very long process - it could be out of range of the Bluefin.

The seabed is sloping in that area so loss of reception may be due to that slope as well as battery levels decreasing.

Standard sonobuoys, modified processors in the aircraft.

Ocean Shield & HMS Echo
 

The graphic below shows the most current tracks for Ocean Shield in Yellow, while those of HMS Echo are in White. The earliest TPL towing tracks for Ocean Shield are Red. The stars shown represent the approximate positions of received pings, as the data provided by AMSA wasn't specific.

http://oi60.tinypic.com/23mi5j.jpg

NOTE: The positions are obtained via a sun synchronous satellite which is in sight of the vessels for 3 or 4 south going passes and the same for north going passes each day.

Utter blonde moment on my part! good point, forgot any receiver would require a power source too and probably in excess of that used up by the ULB.

What does AIS say for the search area when MH370 went down?
 

Been purposefully not posting on this thread given the volumes etc but had an "interesting thought" last night.

Question: Is it possible to go back in time on AIS and look at what ships (if any) were in the current search area at the "best guess" time MH370 would have run out of fuel on that track?

Same would apply for early AIS paths crossing the track MH370 is suspected of taking.

Since the AF447 incident SATCOM capabilities have hugely improved. INMARSAT is providing far higher bandwidths from its new geostationary satellites as they have different antennas with smaller footprints within the overall geostationary footprint some of then steerable. INMARSAT is now offering 'mobile ISDN' at speeds from 64 to 128Kbit

Iridium is launching a new series of low earth orbit satellites (Iridium Next). Iridium satellites are rather like orbiting cell phone base stations and users have a 'connection oriented' datalink to the satellites. Again the data rates have been increased by orders of magnitude. Iridium already sells a system called SkyTrac that does much of the flight following task being discussed here.

With communications things are changing extremely fast.

thommo101, #9906:

There various schemes that could be used to mitigate that. For example, the beacon receiver could be switched on for just a short period, much as the transmitter is, to minimise the duty cycle. If the surface ship sends continuous pings at a sufficiently high rate, the receiver only has to catch one of those during it’s short on period. That then wakes up a microprocessor, enabling power to the transmitter, which starts sending back replies.

Also, 77mW sounds a bit high to me. A simple listening receiver should be doable for much less than that if low power operation is a design requirement…

We are still being subjected to posts about cell phones from MH370
The mods have done a great job removing most but there are still over 180 posts remaining on this thread.

Please, is it too much to ask that you read them - and also the many replies to them - before posting more?

ULB Power
 

So, why not maybe change the ULB specs to slow the pinging down after the first week by halving the rate for each succeeding week.

Or conversely have the longer silent for at least 48hrs, maybe even a week or more.

In the first 48 hours we have the ELB, then there is the inevitable transit time for suitably equipped surface vessels to arrive on the scene. Had it been the South China Sea 48 hours would have been fine.

I dont think that just position reports via satellite should be a problem. For example, in Germany all EMS-helicopters are fitted with a sat-datalink via Iridium and position/status reports ( incl. speed, course and height ) are transmitted every 2 minutes. And you dont need big antennas too, they are as small as GPS antennas. AFAIK Iridium covers almost the whole earth?

There is no added safety with new recorders or continuous transmission , the only difference being that it may be found by now and a story about what happened, although nice to know still resulted in the deaths of 239 people.
If you picked up a live hijacking and shot down the aircraft then the result is the same as the ocean crash.
All aircraft boxes need CIrcuit breakers to protect wiring and prevent fires , they can all be turned off and that cannot change.

Alloyboobtube
 

Disagree. With new tech we can help prevent the next airplane go missing and save its occupants. If we just shrug, we'll eventually get more of the same type of accident as this.

However, by making a circuit breaker smart it can report if it was manually tripped ( = tampered with, unless there was a good reason) or by overcurrent.

As a matter of interest, Hishamuddin has tonight denied the FO phone call story.

MH370 Tragedy: Hishammuddin refutes newspaper report co-pilot made phone call - Latest - New Straits Times