Missing Malaysian Airlines MH-370 - Thread 6

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keep poking, Claig. You're a bit late to this one, I guess you need to catch up on your bickering quotient.

I don't get that impression at all claig. We've all chatted and speculated to a greater or lesser extent across five threads.

Mind, those were in Chat so not in your usual search area...

I am late because I don't know what is going on and have not therefore contributed, but I don't like seeing people trying to stop people speculating by saying "Perhaps what I should have said was that some people need to calm the fuck down?"

OK, if I am wrong, I apologise. i have only read the last few posts and that is teh impression I got from what mileysorearse was posting.

The relatives are perfectly entitled to speculate, it's their tragedy. The swivel-eyes ghouls, not so much. Some posters here that seem to be enjoying the drama a bit too much and that makes me uncomfortable.

I am sorry I mentioned my friend.

Heh, nobody knows what's going on! That's the problem! Gracious reply, thanks.

The debris found by China unrelated according to news

Objects have retrieved but have not been confirmed to be related according to both BBC and Sky, no news that they are unrelated.

Objects have been retrieved

R4 was saying that they didn't look like they came from an aircraft CS.

To my mind the longer no debris turns up, the more concern there is about the totality of the Inmarsat data.

Is it really incompatible with a Northern route ?

For anyone to make anything of this they still need the basic hourly arc data (not talking about Doppler), and they're just not releasing it.

That is the big question, imo, Achy. I don't imagine I could make a whole lot of sense from the raw data stream ... but the teams say they extrapolated distances with great accuracy. They have times, so that should have given them estimated speeds. The line chart they published - to show how the southern arc was compatible with other findings, while the northern was not - had a large peak at the beginning, labelled 'possible turn'. Possible turn from which way to which?

Data, as released by Inmarsat & Malaysia.

"the teams say they extrapolated distances with great accuracy."

Distance in one dimension only. Back to the ripples I. The pond -if I drop a stone in the centre and I know that an object was on the 10m out ripple at midday and on the 20m out ripple at 12.05, I don't know if it went "the shortest distance" between the two ripples ie perpendicular to the ripples, or a much longer distance, necessitating a greater speed, by heading off almost parallel to the ripple and at only a slight angle.

(The ripples are frozen in time, BTW)

Fair point! All the other data, including the 'burst frequency offset' doppler readings, have been made upon assumptions about speed though ... As they based the model curve on readings from known flights, they must think they know what speed MH370 was doing between pings.

I also don't understand what the 'possible turn' implies, or whether there's significance in the projected routes crossing over at something past ten. Can any mathematicians here assist this puzzled poster??

"Fair point! All the other data, including the 'burst frequency offset' doppler readings, have been made upon assumptions about speed though ... As they based the model curve on readings from known flights, they must think they know what speed MH370 was doing between pings."

It's more direction than speed though from the Doppler. There will be a frequency shift related to whether the aircraft is travelling one way or the other along the arc (and bear in mind it might be travelling along the arc, at an angle to the arc etc). The size of the frequency shift will depend on speed along the arc but this will be more difficult to determine. Bear in mind that it took two weeks to even extract the directional data as the data collection isn't designed to do that.

Again, if the plane was travelling 10 miles a minute south on the arc and 2 miles a minute west (a fairly shallow angle), I don't know if, even if the data was perfect, it would be possible to distinguish that from travelling 10 miles a minute south and 10 miles a minute west, which is obviously a 45 degree angle to the arc and gives a much greater absolute speed.

The possible turn is the last military radar point, isn't it?

Think of your ear and sirens - if asked to distinguish between a police car coming towards you and one moving away, you'd be far more likely to get it right than if asked to distinguish between a police car doing 40 mph, 45 mph and 47 mph moving towards you.

But if I had a benchmark - say all the previous police cars I'd heard went 40 mph - I know if the test car was going noticeably faster or slower, wouldn't I? (assuming I had great hearing, which I haven't) They plotted sufficient pings from known flights to provide this benchmark - the green line.

Because, if not, this data's pretty useless isn't it?

I do realise we're discussing minute variations in a 3-point signal that was never intended for this use. It is, however, what we're being asked to accept as the only reliable guide.

My point is, just because they can detect the variation in north and south (which is an effective difference of 800-900 knots) doesn't mean they can detect the difference between 400 and 475 knots.

I think the changed assumption about speed isn't solely based on Inmarsat data - !

Think I may have to give up on this for now Waving goodbye to my fantasy career in space science, Doctrine, and thanking you for your patience!

Garlic

Thanks for that graph, I'd just been searching for it.

There are several queries/concerns I have about it:

1. As you say the "turn"... what can physically account for this "high" data point ?

1. Where do the 3 "measured" data points at 18:25 to 18:29 come from ?

1. What is the explanation for the difference in predicted and measured for the known track up to 17:10 ?

1. Surely there are other Northern tracks that more closely match the data ?

1. And correspondingly there are other Southern tracks which match the data less well than the chosen Southern track ?

1. Why is there no data between 18:29 and 19:40 nad similarly between 22:40 and 00:11 ?

The theoretical southern line and the theoretical northern line are plotted against the actual data and there's close correlation with the southern line (can't see the colours on my phone, sorry!)