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ppauper
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April 29th, 2014, 5:19 pm

QuoteOriginally posted by: tagomaQuoteI'd say "not necessarily incorrect"that is "necessarily correct", right?I said "not necessarily incorrect" because the official searchers dismissed the report because the purported location was not in the official search area. Given that they've been searching the official search area for a while and haven't found anything and keep moving the official search area, it appears less and less likely that the plane is in the official search area.I don't think you can dismiss a report just because it is outside the official search area, hence "not necessarily incorrect".Of course, there may well be (and probably are) other reasons to dismiss this report.And based on all that's happened so far, I'd say ANY report is "necessarily correct" unless and until they physically recover wreckage that is proven to be from the plane
 
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May 3rd, 2014, 4:38 pm

wreckage found by Santa ?QuoteBritish marine archaeologist claims to have found flight MH370 3,000 miles from the search zone after spotting debris painted in the colours of Malaysia Airlines Tim Akers believes he has discovered MH370 debris off the coast of Vietnam He says satellite images appear to show tail, wings and other debris
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ppauper
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May 3rd, 2014, 4:57 pm

Mr Akers (pictured at his graduation) is referenced as an independent researcher with the National Maritime Museumheld back a few years in high school ?
 
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tagoma
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May 3rd, 2014, 6:27 pm

QuoteOriginally posted by: ppauperIf I understand well the situation as of today, the missing plane is probably somewhere.
 
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farmer
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May 10th, 2014, 12:44 am

I read this analysis skeptical of the satellite doppler interpretation. One thing I have not heard mentioned is jitter and drift in the frequency of the crystal used to create the pings.In cellphones, a cheap crystal is used which cannot hold a frequency at all. So each time it registers with a tower, it must first adjust for its own error to synchronize with the tower frequency. It is possible to spend a lot of money to make very stable oscillators for both the plane and the satellite. But no matter how much money you spend, it seems safer to give the plane the ability to adjust its frequency to match the satellite. This is especially true considering a slight drift in the frequency of the oscillator on the satellite could not be fixed. Unless the satellite were also self-tuning, to match a ground frequency in Perth.In any case, it makes sense that either the plane, or both the satellite and the plane, can tune their frequencies to synchronize with partners. It sounds like the Inmarsat system has been around a while. So it is likely that rather than trying to achieve perfect tuning, its protocol allows for a large amount of jitter and drift, rather than trying to get perfect synchronization. It therefore seems possible that the allowed jitter or drift between pings acceptable to the system, is around the same size as the frequency variation attributed to airplane speed.The round trip time would not be affected. Therefore, the distance of the plane to the satellite would be correct. But the shape of the arc, and therefore the location of the plane at that distance, would be wrong if the oscillator frequency has drifted. The search area would be much wider. Lucky oscillator errors could have made those pings zig-zagging around the South China Sea near the original flight path. Or the radio could have been in the water in a swift current, or in a fishing net, I don't know the minimum rate of movement away from the satellite.I am sure these smart guys know the frequency error of their own equipment. Or who knows, maybe they don't. To me, it seems like the plane will either 1) have an unknown frequency error if it does not tune its own frequency, or 2) will tune its frequency to match and cancel out the doppler shift. Maybe someone smarter than me can disagree.Estimating the error based on the frequency on the runway, or using the runway frequency as a baseline, could have problems. Frequency could drift significantly from small temperature and even humidity changes after the plane took off. Batteries or power sources could change voltage after flying for a while. The jet engines could have some resonant frequency that triggers increased jitter at certain speeds.In my experience, oscillator circuits with AC couplings are not random number generators, but like the surface of a lake which registers many small events. If the temperature of the capacitors is not controlled, it could perhaps change the apparent voltage at the crystal. If the structure of the circuit changes temperature during flight, it could deform slightly, changing the proximity of wires, and the accidental coupling between circuit components, feeding back into voltage and resistance, and resulting in a frequency change that could be equivalent to a few miles per hour in estimated airplane speed.One thing not mentioned in the analysis at the link, is possible error in the satellite frequency if both 1) it tunes its frequency to a ground station, and 2) this tuning was not designed to compensate for the decay in orbit where it is no longer stationary relative to the ground station. Again, this is too complicated for me to think about, so maybe somebody else can comment.Figuring in this error could be what is missing in the analysis at the link. But even if you know this error, you still cannot know the error on the plane. It might even be possible that the satellite resynchronized with Perth during the round trip back from the plane. And that there is no record of the size of the adjustment, other than what you can guess based on variations at Perth not accounted for by doppler shift from known orbit instability.When you figure in atmospheric interference, the error might be much bigger than the variations used to estimate plane speed, or it might be too small to matter. It is beyond my expertise.
Last edited by farmer on May 9th, 2014, 10:00 pm, edited 1 time in total.
 
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May 10th, 2014, 7:12 am

Obama as a beauty pageant: "Destroying rain forest is bad"
 
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ppauper
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May 10th, 2014, 7:20 am

the plane doesn't seem to be where they said it wasthere may be proprietary secrets involved, but it would probably be helpful if they released the data they have to, I don't know, MIT ? Cambridge ? and let those folks analyze it and see what they come up with for a likely location or whether they say that the errors are so large the plane could be anywhere.Even in the jungle with the pirates and the parrotsThey may well agree with mr farmer
 
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May 18th, 2014, 2:13 pm

Malaysia Airlines, Whose Flight 370 Vanished in March, Grapples With Financial Difficulties
 
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ppauper
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May 19th, 2014, 6:03 am

conspiracy theory
 
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May 24th, 2014, 5:58 am

Scientists question methods and the politics of the MH370 search QuoteThe acoustic experts, who do not wish to be identified, said the four crucial signals detected by a US pinger locator were almost certainly not from the missing Malaysian Airlines plane?s black boxes, but from another man-made source.They insisted that the signals were in the wrong frequency and detected too far apart to be from the boxes.?As soon as I saw the frequency and the distance between the pings I knew it couldn?t be the aircraft pinger,? one scientist told News Corp Australia.
 
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ppauper
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May 24th, 2014, 5:58 am

pakistan
 
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May 29th, 2014, 7:53 am

searchers rule out area where 'pings' heard
 
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ppauper
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May 30th, 2014, 6:23 am

QuoteOriginally posted by: ppaupersearchers rule out area where 'pings' heardMH370: Missing Malaysian Airlines 'Not Where Search Was Looking' Quote"Our best theory at this point is that [the pings were] likely some sound produced by the ship... or within the electronics of the towed pinger locator," Michael Dean, the US Navy's deputy director of ocean engineering, told CNN."Always your fear any time you put electronic equipment in the water is that if any water gets in and grounds or shorts something out, that you could start producing sound."A spokesperson for the US Navy later described Dean's comments as "speculative and premature" - despite the fact they appeared to have been backed up by the Australian agency leading the search.The spokesperson told the American broadcaster: "I am not saying that what Michael Dean said was inaccurate but what we are saying is that it is not his place to say it.if true , that's bizarre and mickey mouse:wouldn't it make the same noise every time you used it, so they should know about it ?
 
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tagoma
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May 30th, 2014, 10:38 am

QuoteOriginally posted by: ppauperQuoteOriginally posted by: ppaupersearchers rule out area where 'pings' heardMH370: Missing Malaysian Airlines 'Not Where Search Was Looking' Quote"Our best theory at this point is that [the pings were] likely some sound produced by the ship... or within the electronics of the towed pinger locator," Michael Dean, the US Navy's deputy director of ocean engineering, told CNN."Always your fear any time you put electronic equipment in the water is that if any water gets in and grounds or shorts something out, that you could start producing sound."A spokesperson for the US Navy later described Dean's comments as "speculative and premature" - despite the fact they appeared to have been backed up by the Australian agency leading the search.The spokesperson told the American broadcaster: "I am not saying that what Michael Dean said was inaccurate but what we are saying is that it is not his place to say it.if true , that's bizarre and mickey mouse:wouldn't it make the same noise every time you used it, so they should know about it ?The double question is who has been hiding what from the start?
 
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June 5th, 2014, 9:15 am

400 oil palm trees removed from riparian reserve
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