How Satellite Company Inmarsat Tracked Down MH370 491
mdsolar (1045926) writes "Malaysian Prime Minister Najib Razak has announced that, based on satellite data analysis from UK company Inmarsat, Malayian Airlines flight MH370 ended in the southern Indian Ocean, and no one on board survived. 'Effectually we looked at the doppler effect, which is the change in frequency, due to the movement of a satellite in its orbit. What that then gave us was a predicted path for the northerly route and a predicted path the southerly route,' explained Chris McLaughlin, senior vice president of external affairs at Inmarsat. 'What we discovered was a correlation with the southerly route and not with the northern route after the final turn that the aircraft made, so we could be as close to certain as anybody could be in that situation that it went south. Where we then went was to work out where the last ping was, knowing that the aircraft still had some fuel, but that it would have run out before the next automated ping. We don't know what speed the aircraft was flying at, but we assumed about 450 knots.' Inmarsat passed the relevant analysis to the UK Air Accidents Investigation Branch (AAIB) yesterday. The cause of the crash remains a mystery."
Executive summary... (Score:5, Informative)
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uhm, unlikely, unless the plane pancaked/bellyflopped in with no forward velocity ... which is pretty much impossible since it was flying and is an aerodynamically stable object (it wants to point the noise into the wind, even without a pilot).
Its more likely the last thing that went through his mind was his face or glass/instruments from the cockpit, but probably a lot of ocean too.
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Little disturbing (Score:5, Interesting)
Did the Malaysian government just make a statement to the families based on a statistical probability?
Or did they make that statement based on debris found that was positively identified to the aircraft.
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The Malaysian government has mishandled communication from the start. I think they just want this whole thing over and done with. The ones in power over there aren't exactly used to being criticized like this.
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The published text of the PM's speech makes it clear its based on the analysis (what you are calling "statistical probability") not debris or black box.
I don't know why anyone would find that disturbing.
Even if he had debris, for any given family there would still be some "statistical probability" that their loved one survived (infinitely close to zero) involving some sort of miracle, a hidden parachute or a missed connection, etc. Just as we'd discard such false hope, pretending that there is some other pl
Re:Little disturbing (Score:5, Insightful)
I don't know why anyone would find that disturbing.
In Tres Roeder's "A Sixth Sense for Project Management," he shows a diagram of communications. This diagram shows information versus time.
In the beginning, information is unknown; then the information changes, back and forth. For example: a dollar estimate may be $3,000 for a project, then $85,000 when we realize we need to excavate cabling tunnels for a line, then $6,000 when we realize we can run this across our existing tunnel and have a new fiber optic pulled for $3,000, then $7,000 when we realize we're going to also need a new transceiver, then $4000 when we find out some of the other equipment is unnecessary, then $14,000 when we realize the scope of labor required is twice as big.
Finally, once we have enough information, that figure stays. Perhaps at $14,000. We also realize we've got the correct figure because we have a full analysis of scope and work required--or at least, the figure won't change until we've done a bunch of work and realized, deep into the project, that we missed something. In any case, it is now not likely to change simply because our information base is hot.
During the initial planning phase, communication should reflect this: the understanding of the situation--the lack of precision--and what is being done to pin that down is to be communicated; conclusive statements should not be communicated because the current understanding of the situation is inconclusive. Once the situation has reached a point of conclusion, then you communicate these conclusions.
What is disturbing about the Malaysian government here is they have been repeatedly saying, "We have no idea what's happening and there's a ton of information out there we're missing; but this is what happened." Then, five hours later, "Oh we found more debris, we think this happened instead." Then the next day, "Oh there was some satellite telemetry information we weren't done analyzing, but it's provided additional information, so we think the plane may have gone this way..."
In other words: They have piles of information they know they're missing, piles of information they have a plan for finding (i.e. "ongoing investigation"), and huge and visible gaps they know exist and expect to fill. They should not be communicating any conclusions at this time.
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There are supposed to be several salt-water activated beacons that should have been activated. You don't find it disturbing that every one of those failed?
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No, it took 5 days to locate Air France 447 from the debris. It took a further two years to get as much wreckage as we could get off the oceans and to find the black boxes.
The thing is, within hours of Air France's demise, we knew approximately where to look and
Re:Little disturbing (Score:4, Insightful)
This story is so strange (Score:4, Interesting)
It just seems like they have information that still doesn't make sense for what we're told are the available resources. The public info just seems so selective as if each government is trying to hold their surveillance cards as tightly as possible. And, intel from an old satellite seems like a cover story. This is all just so...off.
Re:This story is so strange (Score:4, Interesting)
I thought that maybe a bunch of spy satellites picked up and stored the broadcasts, and that they can use timestamps from the various receptions to triangulate the position. That's sort of a reverse-active GPS.
Of course they'll never say "we got this from U.S. and British spy satellites" so they make up something about doppler shift data from a single satellite and hope they find the debris soon to corroborate the story.
Or maybe they did do it all from the doppler shift data they happened to store. It's at least plausible, and there's no need to create conspiracy theories when they aren't particularly shocking.
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This [wired.com] is the most credible explanation I've seen thus far. (It was mentioned here a few days ago, but I'm too lazy to track down the link right now.)
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To summarize:
Fire on board the plane.
Pilot diverts to the nearest safe airport (which is approximately line with the sudden course change to the west).
Flight crew runs through the fire checklist, which includes pulling all the breakers in case it's an electrical fire (Transponder and communications lost).
Fire causes decompression, pilots bring the plane down to 12,000 ft to remain conscious and keep the passengers alive.
Crew is overcome by smoke and/or decompression, plane flies on under auto-pilot until it
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Yes.. this whole incident is going to make great fodder for conspiracy theories for years to come at this rate.
I would like to coin the theory right now that there was a second plane that extracted all the passengers mid flight and carried them the rest of the way. After everyone was taken off the plane it was allowed to fly on until it ran out of fuel.
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There is very little reason to have spy satellites in the south Indian ocean.
Inmarsat is one of the few companies needing coverage down there because they have the contract for ACARS data an occasional sat phone calls. This area is not even on normal shipping routes.
Mystery? (Score:5, Insightful)
The cause of the crash isn't a mystery. It most likely ran out of fuel.
The cause of why the whole damn plane went AWOL IS a mystery.
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If it simply ran out of fuel, it should have made controlled water landing and likely floated, with plenty of people exiting the plane with life vests on.
chances of controlled water landing are slim (Score:3)
It's virtually impossible to land a large plane in the water "safely"; if either wing or engine touches the water before the other, that side digs in and the plane cartwheels, ripping itself to shreds.
The hudson plane landing wasn't a miracle because of skill on the part of the pilot - it was a miracle because it was astronomically slim odds that the plane would continue in a straight line and remain intact.
How can they be certain no one survived? (Score:3)
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Yes, that could be. But it seems clear that the plane was not being controlled by anyone who wanted the plane or its passengers to be rescued, so "oh, I've just flown the plane as far away from civilization as possible and I've just run out of fuel, yet I think I'll try at the last moment to make a successful water landing so as many people as possible can be saved" just does not seem likely. Either the plane was not under control, or those in control were not trying to save anyone.
And more specifically I s
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The calculations show the southern flight path and consequently a water landing. But...how can they be so certain that no one survived? Isn't it possible that the airplane made a controlled glide into a non-powered water landing and that the life rafts deployed and allowed some of the passengers to survive? That has happened before. Admittedly this is very unlikely but can anyone at this point say it is impossible as the Malaysian government is doing?
Each life raft has an EPIRB [wikipedia.org] which is marine rated, and can be picked up by sattelites basically anywhere on the planet. At least one EPIRB would be of the automatic type which starts transmitting when it hits water. The EPIRB is wrapped up deeply inside the packed life rafts, so disabling them would be impossible while the plane was in the air. Unfortunately this means that if the life raft doesn't deploy and instead sinks, the EPIRB will not go off. The fact that no EPIRB signals were transmitted indica
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They haven't tracked it down (Score:4, Insightful)
They have a theory, nothing more. Still no actual debris has been confirmed. They don't have the full picture so its REALLY easy for their theory to be wrong.
God you suck ass at actually posting facts slashdot.
a bit less specific (Score:2)
Reciprocal course? (Score:2)
I may be wrong, but looking at the map it seems the plane was on exactly the opposite course from where it should have been going. Strange problems are not unknown with computer-controlled navigation systems going haywire when crossing the Equator, and oddly enough MH370 went AWOL quite close to the Equator...
http://www.theregister.co.uk/2... [theregister.co.uk]
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Sorry, the story I linked to related to the International Date Line not the Equator. I was thinking of the much older stories about an F-14 or F-16 that flipped upside down when it crossed the Equator due to some software bug. Here is a reputable source for that (but only as a rumour): http://www.yourdonreport.com/i... [yourdonreport.com]
US Intel Said this on Day 1 (Score:5, Interesting)
What's most interesting is that the anonymous reports from the US intelligence community the day after the plane disappeared said that the plane was on the bottom of the Indian Ocean. These claims seemed a little odd at the time since there was no supporting evidence at all and rescuers were still looking for debris on the original flight path. But, it's looking like they were spot on.
I'm going to go out on a limb and suggest that the only real conspiracy in this whole affair is the US govt's cover up of the initial leak. The plane itself likely just suffered a catastrophic failure and lumbered on until it ran out of fuel. But, the US govt also likely tracked it the entire time. That's why someone was able to make a confident pronouncement so quickly. They knew exactly where the plane was, if not exactly what happened. But, this intelligence capability (tracking all flying objects all the time) is probably highly classified. Rather than give it up for a civilian SAR effort, they decided to keep it under wraps, knowing that eventually the plane would be found and the capability is far more useful if no one knows it exists.
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Why? (Score:4, Insightful)
* We've had flight recorders on all major airliners for decades now.
* We've had satellite phone technology for decades now. (since 1979 for Inmarsat)
Remind me again why "black box" style cellular data transmitters aren't required to be transmitting cockpit voice data and full telemetry from every major airliner at all times yet? With a system like that, installed in a way that can't be tampered with by the people in t he plane and runs independently of the rest of the electronics in the aircraft, there's no reason we would know the exact location the plane went down and, most likely, why. Hell, even if they decided to be cheap and only have it transmit the telemetry in once-a-minute updates we'd still would have know where the plane was to withing a handful of miles from the first day it went missing...
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Remind me again why "black box" style cellular data transmitters aren't required to be transmitting cockpit voice data and full telemetry from every major airliner at all times yet?
Because in the middle of the ocean, there are no cellular towers.
You could do it with satellites, but that becomes cost prohibitive extremely quickly.
Not to mention that there just isn't enough bandwidth to do what you're proposing for every plane.
As a compromise, there's a company looking to put ADS-B [wikipedia.org] receivers on satellites.
That way, the existing line-of-sight radio broadcasts from planes can be tracked without an extensive ground based network.
Model dependance (Score:3)
A very plausible scenario from March 18 (Score:3)
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That scenario stopped holding up once we found that the aircraft had maneuvered both vertically (changed altitude) *and* had undergone multiple changes to it's course. It also fails the sniff test as it fails to explain why the pilots didn't follow SOP and don their oxygen masks - which have microphones built into them. The reliance on "aviate, navigate, communicate" is also questio
PR Guys (Score:3)
Effectually we looked at the doppler effect, which is the change in frequency, due to the movement of a satellite in its orbit.
You can tell this is the PR guy and not the tech guy. Firstly, "Effectually"?
Secondly. The Inmarsat-3 F1 satellite is geostationary, it moves little and slowly relative to the Earth's surface. There is effectively no doppler shift due to motion of the satellite relative to the Earth. The doppler shift here would be that of the aircraft relative to the Earth/satellite. The absence of doppler shifts is the reason that Copas-Sarsat geostationary satellites cannot determine surface position of a emergency locator transmitter unless the transmitter sends that information. For beacons that do not transmit location the low-Earth orbit Copas-Sarsat satellites, which have motion relative to the surface, are used to determine location by multiple doppler readings (but it takes up to 90 minutes vs. seconds).
How hard is it to fake debris (Score:3)
Re:Flight recorder (Score:5, Insightful)
They have narrowed down the presumed crash site. TFA states that the Malaysian government takes this data as proof that the plane crashed near Australia. While important evidence, it's hardly proof - we will need actual debris.
The Malaysian government has been widely criticized about it's handling of this affair. They would like to wash their hands of it and go on to doing whatever it was they were doing out of the world's spotlight.
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Both Chinese and French satellites detected large debris in the same vicinity (optical for the Chinese and radar for the French) and spotter planes from China and Australia also report spotting debris in that area. It will probably be some days before they can get enough ships in the area to coordinate a search grid, but at this point it's an almost certainty that they know the rough location of the crash.
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Until they can confirm the nature of the debris and identify that it's from the plane, I should think it's only "almost certain" that someone saw some form of debris, no?
Unidentified debris is just that.
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They have narrowed down the presumed crash site. TFA states that the Malaysian government takes this data as proof that the plane crashed near Australia. While important evidence, it's hardly proof - we will need actual debris.
The Malaysian government has been widely criticized about it's handling of this affair. They would like to wash their hands of it and go on to doing whatever it was they were doing out of the world's spotlight.
To be fair, the Malaysian government is a small body with mean resources, compared to China, USA, Russia, France, Great Britain, Japan, India, etc. The world community has come together admirably (if a little grudging regarding some satellite intel) and thrown enormous resources at this recovery project.
I am somewhat curious why the Chinese are so bent on a quick resolution here. Is it because they really do look after their people? Or was someone or something on the jet they really want know where is or
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You can be a small country with limited resources, but you don't get to excuse for not calling for help when you are clearly in over your head.
Re:Flight recorder (Score:4, Informative)
Which is why they waited literally days before asking the international community for help? Seriously, significant progress didn't begin until the other countries were allowed to start helping.
The first few days the obvious extrapolations from the normal flight path was searched, and that search was not only conducted by Malaysia, so other countries were involved from the beginning. When they realised things were not as simple as that they asked for more international help. I fail to see what they did wrong, even in hindsight.
Re:Flight recorder (Score:4, Funny)
> I fail to see what they did wrong, even in hindsight.
That is because you are not applying the right standard. You see, anytime any effort fails, they, by definition did the wrong thing. Let me explain. Lets say, you have Ace Queen and the flop comes out Ace Ace King, then the a queen and a duece drop.
Now you have a full house, so if you bet and win, you did the right thing, However, if someone else had the king, and wins, you did the wrong thing, because you lost. Even though you had the same information available either way, and the negative outcome was extremely unlikely, by applying this standard retroactively, you made the wrong choice.
I know this may not make much sense, but that is because you are clearly stuck in antiqueted pre-9/11 world thinking where we could take the chance of allowing nuanced arguments that require deeper understanding than could be intuitively understood by a 4 year old.
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While important evidence, it's hardly proof - we will need actual debris.
Why do we need the debris? If the evidence is good enough that governments are willing to issue death certificates to the families, the book on this thing could be closed. Sure its not satisfying especially to the families that might really want the remains found but as a practical matter actually finding the plane won't change much.
Re:Flight recorder (Score:5, Insightful)
as a practical matter actually finding the plane won't change much
Really? You don't think there's much of a difference between knowing it was a mechanical failure (or fire, etc) and knowing it was a deliberate criminal act? If the problem was related to payload or the aircraft's infrastructure or maintenance, you don't think it's vital for all of the other people flying on that same equipment to know what went wrong? If this was done by the pilot(s) at the behest of some organization or state, or otherwise in the service of some agenda, you don't think that's meaningful, in the context of trying to prevent it from happening again? Glad you're so relaxed about it. You probably don't do much business overseas, or ship expensive things that are central to your mission, or have relatives that fly on that equipment or in that part of the world, so that's probably why the death of hundreds and the loss of a huge, expensive aircraft is a yawner to you.
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as a practical matter actually finding the plane won't change much
Really? You don't think there's much of a difference between knowing it was a mechanical failure (or fire, etc) and knowing it was a deliberate criminal act? If the problem was related to payload or the aircraft's infrastructure or maintenance, you don't think it's vital for all of the other people flying on that same equipment to know what went wrong? If this was done by the pilot(s) at the behest of some organization or state, or otherwise in the service of some agenda, you don't think that's meaningful, in the context of trying to prevent it from happening again? Glad you're so relaxed about it. You probably don't do much business overseas, or ship expensive things that are central to your mission, or have relatives that fly on that equipment or in that part of the world, so that's probably why the death of hundreds and the loss of a huge, expensive aircraft is a yawner to you.
Turning off the transponders seems pretty deliberate.
Re:Flight recorder (Score:4, Interesting)
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I could be mistaken, but I believe FDR is here:
http://www.findagrave.com/cgi-... [findagrave.com]
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It is a reasonable assumption that the transponders were intentionally switched off, given the chain of events following the transponders being turned off a
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It is a reasonable assumption that the transponders were intentionally switched off, given the chain of events following the transponders being turned off and the cessation of radio communication
Like that Washington Post graphic shows, the last communication happened 2 minutes before the transponder stopped transmitting, not after. The flight path, both heading and altitude, was erratic. The plane made several turns in different directions, as if they didn't know where they were. The initial heading after communication was lost was roughly in the direction of one of the nearest airports that would have accepted a plane that size. There's no real reason to assume that this was deliberate versus
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You'd think FDRs would float and be mounted in a section of the aircraft that detaches on impact (accelerometer+explosive bolts).
I wonder why they don't do that...
440 pounds of lithium batteries on flight (Score:3)
There were 440 pounds of batteries on one of the cargo items. Fire seems plausible and might explain the alleged radar track to 40k feet. Alternatively other 777 have reported a fuselage cracking problem around the satellite antenna. Decompression from that could explain the dive to below 12000 feet , the loss of some communication ( if the Ping channel a different antenna?) and perhaps incapacitation of the pilots. But this seems less likely.
The most interesting thing about the Inmarsat anaylisis is th
Re:Flight recorder (Score:4, Insightful)
The CVR only records for an hour or two of audio. In all probability, nobody in the cockpit was making noise the last two hours. The FDR would have the whole flight, and will likely show the cause of the crash being fuel exhaustion.
As best I can tell, there is nearly zero chance that there was a fire that turned off ACARS message transmission, then caused corruption in the flight management computer to add several waypoints off the programmed course, then slowly proceeded to short out the transponder 5 minutes later, then caused the VHF radio to stop working immediately after handoff from Malaysian ATC, all the while not impacting the ability for controlled flight of the plane.
Unfortunately, the bat-shit scary truth of the matter appears to be that the pilot decided to kill himself and everybody else on the plane, and there really isn't much that passengers or other flight crew can do to prevent the outcome.
Re:Flight recorder (Score:5, Interesting)
When you step back and actually review numbers, many things seem insignificant, if you have no personal feelings or emotions tying you to the event. Like this post, discussion, and website.
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You aren't going to get the the mechanism of the crash by staring at satellite photos ...
Re:Flight recorder (Score:4, Insightful)
Whether or not there are survivors was pretty much a moot point by March 15. If it was a violent crash into the water, no more than three dozen probably survived impact. Of those three dozen, probably 50% or more sustained fatal injuries that would kill them within 16-24hrs without immediate medical attention. The remainder would have perished within 3-7 days due to dehydration and lack of nuitrition. That's ignoring any exposure related issues, predatory marine life, or drowning. Dehydration, starvation, and miscellaneous death causes would have happened over 3-7 days if it was a soft landing.
Had they, on a slim chance, crashed on land rather than the sea there might still be some chance that survivors lived but that is going to be a hard landing and those that did survivor it may not have been mobile, conscious, or otherwise in a state where they might be able to find potable water or food wherever they landed.
The purpose of finding the plane is not to be able to declare the passengers and crew dead the fact that they waited this long was cruel because it unnecessarily kept hope alive. The purpose is to recovered the recorders so that it can be can be determined what might have happened and if there was any mechanical or electrical issues that would warrant attention for other 777s.
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Isn't there supposed to be several salt-water activated beacons that are automatically released upon a crash?
Re:Flight recorder (Score:5, Insightful)
They're probably worthless, the cockpit voice recorders are only required to have 30 minutes capacity with a recommendation for 2 hours, since we know it was at least 4 hours between the critical event (the plane turning south) and the crash the CVR's won't have any information about the events that matter (I'm assuming 777 uses digital recorders so they won't be able to pull phantom prior recordings like they sometimes were able to on analog recorders)
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If there are voices on it, it might indicate who was in the cockpit. It would be even more telling if there's shouting, such as from a locked-out copilot begging the pilot to turn around, or from the pilot yelling at terrorists that they don't have enough fuel to reach Antarctica and that they're going down into the ocean.
It's only completely worthless if its silent.
Re:Flight recorder (Score:5, Insightful)
It's only completely worthless if its silent.
On the contrary. A completely silent CVR tells you a lot; it tells you that the airplane kept on flying with every one on board either unconscious or dead for at least 2 hours before the crash. That's a critical information for the investigation.
Furthermore, through data/media forensic, you might be able to recover the previous data that was overrecorded, although I wouldn't count on it after 3 to 4 record cycles.
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But if they find a pallet full of burst lithium batteries and bodies that died from smoke inhalation as well as no control from the cockpit for whatever length of time they do have on the flight recorder I think we'd have a pretty good idea.
I basically rooting, at this point, for the pilot to be cleared. Because the unwarranted animosity the press showed towards him based on just about 0 evidence deserves to be punished. Lastly, someone has to shut down CNN at this point. I mean, I dislike Fox and MSNBC as
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zero evidence? There were three people on the aircraft that know how to hide the aircraft like this ... and ALL of them were sitting in the cockpit. If someone else on the aircraft knew how, no one has figured that out yet.
So instead of this being something done by one or two people, you'd much rather it be a systemic problem with aircraft that tens of thousands of people fly in everyday?
You'd much rather the press look bad ... and other people be at risk of death as well?
Thats pretty fucking short sighte
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I'd rather get to the truth of the matter. Yes, we should not be going hog wild speculation until we have some real answers but that could take months or years and our current news cycle can't handle that scale of time. They can't even imagine it.
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Calm down, dude. He didn't say it had to be a systemic problem with the aircraft, just that it wasn't the pilot purposefully crashing the plane. There's still a wide range of things that could have gone wrong before considering it a systemic issue.
Re:Flight recorder (Score:4, Insightful)
So instead of this being something done by one or two people, you'd much rather it be a systemic problem with aircraft that tens of thousands of people fly in everyday?
Actually yes. The last time a 'few' people in cockpit tried nefarious stuff, the world changed and the US (my country) invaded Iraq and started headlong down the road to totalitarianism. A perfect storm really. An already corrupt 2 party system that doesn't do any serious check and balance, only raise money for re-election, now gets a perfect 'for the children' defense for *anything* proposed no matter how stupid or pointless it is.
Or we have a mechanical failure that can be fixed...
I'll take the latter every single time. The above sounds like a rabid libertarian point of view, but I assure you it isn't. I'm as left wing liberal as just about anybody. I believe in government and it having a purpose; but with the NSA and everything else we've seen in the last 15 years...it is truly broken to the core and it's up to us to fix it.
Re:Flight recorder (Score:5, Interesting)
CVRs on those aircraft are 2 hours, not 30 minutes.
What I want to know, is why my phone (the smallest model made) can hold 1100 hours of compressed audio ... but these aircraft using NAND don't hold more than 2 hours of uncompressed audio (you don't want any quality sacrifices or artifacts from compression to screw up your analysis later) in a redundant array ...
Someones going to tell me that for the 30-40k those black boxes cost ... they can't put some actual storage space in the fucking things?
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Or now with in-flight WiFi an option, why isn't the black box configured to upload its audio to a server somewhere?
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Cockpit Voice Recorder [wikipedia.org]
A standard CVR is capable of recording 4 channels of audio data for a period of 2 hours. The original requirement was for a CVR to record for 30 minutes, but this has been found to be insufficient in many cases, significant parts of the audio data needed for a subsequent investigation having occurred more than 30 minutes before the end of the recording.
Flight Data Recorder [wikipedia.org]
Modern day FDRs receive inputs via specific data frames from the Flight Data Acquisition Units (FDAU). They record
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While you can technically call that narrowed, this narrower area is still the broadest search area ever. The Inmarsat pings are only accurate within something like 500km since they are only once per hour events. There is an additional ~10km uncertainty from altitude, probably a few more km due to signal noise since I doubt the Inmarsat satellites recorded the raw RF signal for a real Doppler analysis. They probably deduced the Doppler effect from the carrier lock frequency of individual handshake packets. A
Re:Flight recorder (Score:5, Insightful)
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Still vastly better than what it was only a day ago, and there seems to be a lot more possible debris sightings in the search area which I take as a sign they might be in the right area and will hopefully pin it down some more. The race now is to find it before the black box transmitters go silent, a task for which the US is dispatching some specialist search gear apparently, because that's probably the only hope of giving the bereaved a chance at some closure left now.
They may be a lot closer to the area where the plane went down, but they are still far from finding it. After all, the debris, assuming it's from the plane, has likely drifted a long way from the original crash site. Even if they are able to track back the debris by modeling the ocean currents in the area and cross referencing that with the flight path, the remaining search area is still going to be huge. Unless the search teams pick up the blackbox signal before the battery runs out, we may never know w
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Re: (Score:3, Funny)
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And the only hope to prove it was not a software glitch that took offline all the communication systems and locked out the pilots.
There are no manual overrides for a fly by wire system, and you cant reboot it mid flight.
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That is what multiple redundancies are for. Unless this "glitch" not only shut down the radio and transponder, but took the aircraft on a new flightpath by itself, what you're suggesting is not at all likely.
Re:Flight recorder (Score:5, Funny)
Still vastly better than what it was only a day ago, and there seems to be a lot more possible debris sightings in the search area which I take as a sign they might be in the right area and will hopefully pin it down some more. The race now is to find it before the black box transmitters go silent, a task for which the US is dispatching some specialist search gear apparently, because that's probably the only hope of giving the bereaved a chance at some closure left now.
Forget the bereaved, how on earth will the media ever get closure if the plane isn't found?
Re:Flight recorder (Score:4, Insightful)
I appreciated the joke, but on a more serious note...
The media don't get closure, they get amnesia.
Re:Flight recorder (Score:4, Informative)
The Indian ocean is very deep, it is a remote location and two weeks have passed already. This black box will be harder to find than that of the Air France flight which got lost over the Atlantic. Back then they said that the sender of the black box will run for a month. I don't believe that they will find it this time.
There's no doubt that they'll find it, the question is when. As we speak, the remains of MH 370 are sitting on the bottom of the ocean, under 5,000 meters of water, and they're not going anywhere. Nothing is disturbing the wreckage, so it will just sit there for months, years, or decades until someone comes along. The Titanic sat on the seafloor for 73 years until new technologies made it possible to locate the wreckage, and yet it was remarkably well-preserved given how long it had been underwater. I doubt it will take 73 years- technology has advanced a lot, and continues to advance- but even if it does, the plane will be waiting.
Whether anything useful comes out of the flight data recorders or not is another issue. After 2 years, the data recorders from the Air France flight still worked, I don't know if anyone really knows how long the data would still be good. Solid state memory is pretty indestructible, so if the chips can survive being immersed in saltwater, maybe a long time. The bigger issue is whether the pilot shut down the recorders as well. In the SilkAir crash, the pilot or copilot shut down the flight data recorder and cockpit voice recorder before deliberately putting the plane into a dive. Whoever hijacked this plane seems to have wanted its fate to be a mystery, so there is a real possibility that he shut off the recorders as well. If so, we may find the crashed plane, but if so, we'll never know anything more than what we know now.
Re: (Score:3)
Few hundred? Probably a bit more than that, but at least they have the vicinity. Which is significantly different from other places they were looking.
The Chinese government has been very impatient and hot under the collar about the whole search and lack of answers, yet they also have been coming forward with satellite photos of potential debris hundreds of miles apart from each other. "Hey! Look here!" "Hey! Look there!" "Hey, look way over here, now!" What's taking you people so long finding it?!?
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Contrary to movies, spy satellites do not watch every inch of the planet. Nor can you easily steer them into another orbit for live James Bond style feeds.
ZERO spy satellites point at the open ocean, nothing interesting going on out there.
Re:Flight recorder (Score:5, Funny)
Re:Flight recorder (Score:5, Funny)
They already know about your Skull Volcano island... they dont care because the US government hopes to contract out your services for the "protection" of the American People...
BTW: you have those genetically altered badgers ready yet?
Re:Flight recorder (Score:5, Funny)
The ones with the skunk glands?
Badgers? We don't need no steeeking badgers.
Re: (Score:2)
but various countries have been slow to tip their hands and show just how much the see and can track, lest they give away some very closely guarded secrets.
I would LIKE to think ... that even the NSA would pick up the phone and say 'look, I can't tell you anything other than go to these coordinates: blah blah, we think you might want to see this' and nothing of value would be divulged. We already are aware of what Google has in the area for photos, which is plenty good enough to make a statement like that, so its not like it tells us how much better they see than something like Google Maps.
There are ways to deal with that situation. I'd like to think we'd us
Re: (Score:3)
since its a method they dont normally use maybe they didnt think to use it until 2 weeks past? and also I saw some mention of them passing the info on March 12th, but maybe that was less exact.
Re: (Score:3)
I suspect, and I have zero knowledge of this system, that the satellite used has linear transponders that re-transmit the exact signal it receives. This means that both amplitude and frequency domain are relayed and received at the ground station. I imagine that the ground station is a software defined radio that digitizes and records everything that is passed though the IF.
Again, I know nothing of this system, but if I was going to build one, that's how I would do it.
Re:Some questions (Score:5, Informative)
How come the frequency information of the signal received by the satellite was saved? What is the purpose of saving all that data in normal operations?
The communications system in question is likely based on TDMA (Time Division Multiple Access). While I have not worked with Inmarsat systems, all the other satcom systems I have worked with log each connection, and various pieces of information regarding the connection. One of these parameters that is logged is the frequency offset (ie the difference between the expected and actual frequency). This is useful from a troubleshooting perspective as it allows you to spot transmitter and receiver components that are drifting out of specification. Some of the more advanced satellite systems (iDirect) will actually log the geographic coordinates of the uplink site, as this plays into the timing requirements for the network. Unfortunately, Inmarsat isn't this aggressive with their timing, so time of flight isn't an issue).
And why did it take three weeks to do that analysis?
This is pure speculation on my part, but I would wager they had to go back through significant amounts of logs in order to characterize the transmitter and receiver components on that particular aircraft. The doppler effect is going to be subtle compared to the thermal drift of the transmitter, so they need to factor that out before they can get at the thermal drift. Also every oscillator and transmitter is different, so they would need to characterize the transmitter that is on that specific aircraft (which is now of course missing).
Re: (Score:2)
How come the frequency information of the signal received by the satellite was saved? What is the purpose of saving all that data in normal operations?
And why did it take three weeks to do that analysis?
I thought the same thing.
With digital tuners, what radio system even captures exact frequency these days? Its either in-band our out of band and not heard.
Perhaps these satellite radios are wider band, and therefore they record the exact frequency any transmission arrived, but it just seems unusual to have this information at all, let alone to be able to dig it up out of several days old data.
Re: (Score:2)
Re: (Score:2)
Ask Captain Sullenberger. Oh, and stop being an idiot.
Re: (Score:2)
Re: (Score:3)
No it isn't, its not using data from a system that WAS TURNED OFF within MINUTES of the last radio contact.
How the fuck did this get marked as insightful? Its make a wrong statement that everyone has know has been wrong since the second day.
Re:ACARS (Score:4, Insightful)
No it isn't, its not using data from a system that WAS TURNED OFF within MINUTES of the last radio contact.
How the fuck did this get marked as insightful? Its make a wrong statement that everyone has know has been wrong since the second day.
You should try to keep up with the actual events instead of lashing out on Slashdot.
The DATA transmissions ceased on the ACARS, but the radio system still pings the satellite.
The radio system keeps its link with the satellite as long as the actual transmitter has power.
Just because you stop tweeting on your phone doesn't mean the phone stops talking to towers.
Re: (Score:2)
Probably because ACARS was turned off hours earlier in the flight, back before the aircraft flew back over Malaysia! Had it been active, ACARS would have reported the aircraft's location, altitude, speed and other useful data, making finding it much easier; it was switched off with the other cockpit systems, though, leaving just the Inmarsat terminal's hourly "ping" active, s
Re: (Score:2)
kinda off topic but: the first report i heard was that the plane had four hours of fuel on board. now it is seven? huh?
Where did you hear that? I suggest you try to search for a citation for it and post it here. If there are discrepancies in the story, it's always good to bring them to daylight.