lancelot07
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 6:23 am

Quoting YoungMans (Reply 156):
One ....
The data from this particular satellite has 'always' contained a small error.

They compared with other aircraft at the specific time.

Quoting YoungMans (Reply 156):
Two ....
The data from the satellite has been deliberately falsified.
Quoting YoungMans (Reply 156):
In this scenario, 9M-RMO would have pretty much flown the path as it has been worked out here; the only difference being that it has ended up somewhere else in the Indian Ocean, anywhere except near the search areas covered so far.

If it has flown the assumed path it cannot be nowhere near the assumed end of this path.

Quoting YoungMans (Reply 156):
Three ....
The data may not have been just falsified but was completely fabricated, concocted; this could have been to an extent that not even the satellite company would have noticed anything wrong, at least not initially.
Knowing the electronic call-sign for this particular aircraft (or flight) a sophisticated electronics lab could probably copy that. It could use that then to communicate with the ground station, via the satellite.
The timing of the 'handshakes' (including the BFO's, BTO's and whatever else) could have been changed electronically and the satellite and the ground station would have accepted that as 'stock-standard communications'.
Such an electronics lab could be on land; anywhere really as long as it is within the necessary distance from the satellite. Much easier still would have been for such a lab to be on a ship; and again, that could have been just about anywhere on the Indian Ocean.

They could publish some random numbers, yes.
But to assume they could put the sat modem with faked credentials of MH370 on a ship and fake the data is out of this world. They would need an aircraft, taking off at the same time in KUL, following MH370 closely - ah, forget it !
 
YoungMans
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 6:37 am

Quoting lancelot07 (Reply 159):
They compared with other aircraft at the specific time.

Yes; and the error would or could have been the same on every message the satellite relays.

Quoting lancelot07 (Reply 159):
If it has flown the assumed path it cannot be nowhere near the assumed end of this path.

True; if the data that was collected is the same that we have been given.
That is what I'm suggesting, it may not be the same, it may have been falsified.

Quoting lancelot07 (Reply 159):
But to assume they could put the sat modem with faked credentials of MH370 on a ship and fake the data is out of this world.

Maybe yes, maybe no; maybe it is not really a problem for a sophisticated electronics lab, be it on a ship or on land.
 
NAV30
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 6:38 am

Quoting lancelot07 (Reply 159):
But to assume they could put the sat modem with faked credentials of MH370 on a ship and fake the data is out of this world.

Anyone know whether Inmarsat data is broadcast? As opposed to being received by Inmarsat, and transmitted to the 'clients' by Inmarsat's people?
 
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Finn350
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 6:52 am

Quoting YoungMans (Reply 160):
Quoting lancelot07 (Reply 159):They compared with other aircraft at the specific time.

Yes; and the error would or could have been the same on every message the satellite relays.

No, as the location data derived from the pings can be compared to ADS-B data, and if there were an error in the satellite data it wouldn't match the ADS-B data.
 
NAV30
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 7:01 am

Quoting Finn350 (Reply 162):
No, as the location data derived from the pings can be compared to ADS-B data

Please see my post 158 above, Finn350? It is established that ADS-B went off the air at 01.22hrs.?

[Edited 2014-05-28 00:11:46]
 
sipadan
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 7:18 am

Quoting YoungMans (Reply 156):
Knowing the electronic call-sign for this particular aircraft (or flight) a sophisticated electronics lab could probably copy that. It could use that then to communicate with the ground station, via the satellite.
Quoting YoungMans (Reply 156):
This scenario would have been quite ruthless and would require a sophistication as we have seen it only with 9/11.

Think you'e giving the 'al queda' brain trust a little too much credit here. 9/11 was rather 'sophisticated' by degrees in regards to the planning and execution. The technical aspects of 9/11 really never surpassed flight sim training and crude flying (although the actual skill level of the 'pilots' is something that is still debated today--not that it matters).

So my attitude towards Inmarsat all along has been that they are the de facto face of US Intel (or British). As such, they are acting and behaving accordingly, doing what they're told to do, when they're told to do it. I mean, it's naive to think that they haven't had substantial interaction with said intelligence services, and if you accept that as likely, I would also think it likely that they are in compliance with these respective agencies.

This goes to your second scenario. Clearly they have been holding back. I haven't seen the data (and wouldn't understand it, regardless) but I do recall the Inmarsat president (not the ceo) saying that with the data would be 'explanation'. It seems that this is not the case. Why? Once again they were deflecting and deferring to the 'Malaysians'. It seems clear that they are not interested in the complete transparency they espouse. I understand NDA's and proprietary claims and the like, but it seems a tipping point has been reached (reputation and best business practices). Don't keep preaching and screaming transparency, Inmarsat, as you are being utterly disingenuous. Better that you say nothing at all.

Quoting NAV30 (Reply 158):
How Inmarsat apparently went on 'pinging' a possible western course, I don't know. But all OTHER contact with the aeroplane - and the crew - ended

Okay...what you are saying then is that the aeroplane crashed or whatever, but that the component piece responsible for the communication with Inmarsat 'survived' the 'crash' and kept answering the satellite every hour. So it remained functional after a tremendous impact with the water, remained floating, didn't sink, and then just happened to sink or stop working at precisely the same time as the aircraft's endurance would expire????

Just heard Bluefin not going back to search area until August, and no replacements (Remus 6000 etc...) are scheduled. Mapping seems to be the only priority. Terrible news for the families, I would imagine.
 
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Finn350
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 7:55 am

Quoting NAV30 (Reply 163):
Quoting Finn350 (Reply 162):No, as the location data derived from the pings can be compared to ADS-B data
Please see my post 158 above, Finn350? It is established that ADS-B went off the air at 01.22hrs.?

Yes, ADS-B went off 1721 Z. Up until that time they can compare the MH370 ADS-B track and the ping rings derived from the satellite data, and after that time they can compare all the other planes still tracked by ADS-B and their corresponding satellite data (and that is precisely what Inmarsat & others have done in order to verify their analysis).
 
sejtam
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 8:02 am

Quoting Finn350 (Reply 165):

and afaik they tested their mesasurements again with some flights the following days, maing sure they have good data to compare to.
 
Backseater
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 8:09 am

Bluefin 21 (or other similar device) is apparently not scheduled for another dive before August.
It appears that the major reassessment currently in progress is slow and not yielding any breakthrough.

The official Indian Ocean search strategy so far has been largely predicated on a steady southbound flight "immediately" after emerging from the Strait of Malacca. I have emphasized the word "immediately" because according to the Preliminary Report, the a/c is so eager to rush into oblivion that it clips the northern tip of Sumatra.

That is interesting, particularly if you want to be seen by radar on your way to nowhere. I am not talling about the secondary radar at Banda Aceh that the a/c probably overflew. Around the northern tip of Sumatra there are two primary radars: one near Sabang on Pulau We island (THomson TRS 2215 D?), the other near Lhokseumawe (Thomson TRS 2215?). Apparently the one in Sabang is tasked with looking eastward towards the Strait of Malacca whereas Lhokseumawe looks westward towards the Indian Ocean area. Therefore, according to the Prelim the a/c flew right in between the two radars and should have been painted by both.

Indonesian Defense Minister Purnomo Yusgiantoro stated that on Wednesday March 19th, his Malaysian counterpart contacted him to ask for help in the search for the missing MH370 Malaysian Airline. He said he had informed President Susilo Yudhoyono of Malaysia's request. The President discussed the request at a cabinet meeting on Wednesday evening. Pumono said that Indonesia has committed itself to help its neighbor find the airplane. Pumono also added that "the Indonesian military radar placed in the country's western-most city of Sabang is strong. It did not detect an airplane flying over Indonesian territory".

What I am driving at is that 9M-MRO may not have been so eager to reach the Diamantine trench after all. From IGARI to the air defense point at 18:22, the path was IMO designed to keep looking friendly to Malaysia and not venture in either the Indonesian or Thai FIR while flying northwest bound up the Strait of Malacca. The a/c was flying directly away from Malaysia/Butterworth AB (=friendly) and slowly but surely getting further away from both Indonesia and Thailand (=noalarm). After reaching the physical limit of detection by Butterworth, descending would also have made the a/c disappear from both Indonesian and Thai radars, if they were watching. Those radars are supposed to be 3D but with a 3dB vertical beamwidth no better that 1.5deg (est), altitude estimates at long range should be very poor. Indonesia might have assumed that the a/c was flying towards the Thai FIR (=Thai problem) and conversely.

I am suggesting that after exiting the Strait of Malacca, 9M-MRO may have loitered for a while (N, NE, N, NW, W, SW, S, SE), at slow speed (max endurance?), possibly waiting for some event (via HF?), meeting the early ping rings by accident, moving eventually to a southbound then southeast bound route patterned after the western coast of Sumatra and then Java. The a/c could have penetrated the Indonesian FIR without any risk of challenge provided its altitude remained below the radar horizon for any radar that might be along the coastline.

That is of course only one class of piloted scenarios among many, many others. It only shows that the a/c could plausibly be in many different places, including close to Java. The official team may have just decided to keep the funds they have set aside for underwater search until a physical piece of evidence shows up somewhere and hopefully narrows down the search domain to a manageable and affordable task.
 
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Finn350
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 8:20 am

Quoting BackSeater (Reply 167):
That is of course only one class of piloted scenarios among many, many others. It only shows that the a/c could plausibly be in many different places, including close to Java. The official team may have just decided to keep the funds they have set aside for underwater search until a physical piece of evidence shows up somewhere and hopefully narrows down the search domain to a manageable and affordable task.

As far as I understand, the delay in (re)starting the underwater search is related to the acquisition process: they have to map the underwater area, define the scope of the underwater search, draft a request for proposal, get the proposal from the potential commercial vendors and reach an agreement on a commercial basis. This will undoubtedly take a couple of months.

Regarding the flight path published in conjuction with the preliminary report: it might be that the flight paths in itself don't matter, it is only the possible end points on the final arc that are really meaningful. Even if the flight path crosses north of Sumatra, it might be one of several alternatives which will reach the same point on the final arc using the same constraints (average ground speed, available fuel).
 
YoungMans
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 8:26 am

Quoting Finn350 (Reply 165):
Yes, ADS-B went off 1721 Z. Up until that time they can compare the MH370 ADS-B track and the ping rings derived from the satellite data, and after that time they can compare all the other planes still tracked by ADS-B and their corresponding satellite data (and that is precisely what Inmarsat & others have done in order to verify their analysis).

Quoting sejtam (Reply 166):
and afaik they tested their mesasurements again with some flights the following days, maing sure they have good data to compare to.

Yes, that's all true but ....
After the ADS-B stopped, wouldn't all the other tests have been conducted through the same satellite?

In other words, if the satellite did have a small error (in time stamping) in its workings, that error would be constant right across the board, i.e. with every message it has ever received and relayed.
(I don't know how I can express this better to make the point...)

However small or big that error may be, it could (perhaps) be enough to skew all distances.
 
Backseater
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 8:44 am

Quoting YoungMans (Reply 169):
In other words, if the satellite did have a small error (in time stamping) in its workings

The satellite is of the bent pipe type. It receives data from an antenna in some frequency band while transmitting the same through another antenna in another frequency band. It neither stores any a/c data nor time stamps anything. In the case of 3F1 everything is received/calculated/archived by the GES in Perth.

If any questions have to be raised re. latency errors, I would first look at the airborne satcom (AES) given a few strange BFO/BTO values in the raw data.
 
Pihero
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 9:16 am

I've been quite busy with some rather important subjects these past few days, like the H Cup final, the European elections and some reports to complete on training and recruitment.

I see with pleasure that the publication of the Inmarsat log has validated quite a few of my posts :

1/- My avionics engineer friend has been right all along : the communications between the satellite and the Satcom are just about continuous ( and bear in mind that the log is by no means complete ) ... it was just that the 7 data points are based on one channel - R - only.

2/- Unfortunately that publication doesn't solve anything for the lay public : Missing is the *processing time within the ground station, the satellite and the aircraft terminal, which is constant*... but not released.

As per Inmarsat : "Understanding the Burst Timing Offset (BTO) values:
The round trip time for a message is a combination of:
1 Time from the groud station --> satellite--> aircraft--> satellite--> ground station
2 Processing time within the ground station, satellite and aircraft terminal, which are constant
The BTO is a value (in microseconds) relative to a terminal at a nominal fixed location. Only R-Channel messages are used.
The BTO therefore allows the determination of the distance between the satellite and the aircraft
"
... So I'm quite surprised that suddenly, a lot of assupmtions are made - but why am I not surprised ? - on the Inmarsat *loci*

3/- Our friend WP doesn't have any qualms at all.
After acknowledging :

Quoting WarrenPlatts (Reply 86):
3. Then we're given a BTO value in microseconds that seemingly has no relation to the actual speed of light travel times: e.g., for the 24:11 ping ring we are given 18,040 microseconds = 0.01804 seconds, far shorter than the actual travel times.
...The BTO is supposed to be "relative to a terminal at a nominal fixed location", but which terminal and what nominal fixed location?!?
I must confess to being thoroughly confused at this point. Maybe someone else can make sense of this.

... it doesn't prevent him from getting out of his hat this gem, based on really thin air :

Quoting WarrenPlatts (Reply 103):
I will say that the "7 Data Point" is inconsistent with a ISBIX MUTMI RUNUT flight path, whereas the Hussein Chart data series lines up perfectly. Thus, if it is the case that a southerly waypoint path was taken, then that would seem to imply that the Hussein Chart data series should be preferred.

Of course, not mentioning the fact that Mr H's - and his - trajectory still has to match the time / fuel / altitude constraints anybody with a modicum of aviation knowledge expects... and we are still waiting for exact coordinates of the intersection points between that trajectory and the - revised - ping rings.
... but there is hope : we are watching a silent and stealthy move towards another set of speeds ( apparently not a constant 491 kt grounsd speed any more. )... and another scenario, may be not based on the same waypoints   

So... I'm back.

Quoting Finn350 (Reply 155):
Quoting WarrenPlatts (Reply 126):
I'm starting to get a little worried about Pihero--
Don't worry. He is probably recovering from the realization what the most likely scenario for the disappeareance of MH370 is (and to lesser extent that his pet theory 'IGARI direct to north of Sumatra' is ready for vertical archiving based on the ATSB publication).

... and why should that be ?
Has anyone proven that without my knowledge ?
Have you ?

Finally... to demonstrate the dishonesty inherent to all WP's posts, he gently marks a point on his last pretty picture ( post # 106 ) as *Pihero crash site... Unfortunately, he neither mentions that that point I proved impossible ( time and fuel constraints )... or does he - as a matter of honesty - mentions the S 21.45 / E 103.50 which is right in the search area, and which I mention just as an illustration of the possible end of the flight as per AAIB / Inmarsat... study, which I might remind you, has been reviewed and approved by all involved in the search for Flight 370.
Contrail designer
 
Backseater
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 10:51 am

Quoting Pihero (Reply 171):
1/- My avionics engineer friend has been right all along : the communications between the satellite and the Satcom are just about continuous ( and bear in mind that the log is by no means complete ) ... it was just that the 7 data points are based on one channel - R - only.

Welcome back. Hate to be a party pooper but what was he right about?
1) "To him, it is disingenuous to say that we only have ten loci... It could be one hundred and probably more..."
No, 7! As I explained at the time, the GES only gets reliable RTDs on a few specific messages (logon/logoff acks). Confirmed.

2) "When asked how accurate the *loci* could be, he said : their width could be determined to a precision of ten meters, but the problem is assuming an altitude, that would introduce an error of up to 500 meters, maybe a bit more, but I'd be surprised if the lines are determined with a margin of more than a kilometer."
Based on the standard deviation estimate I computed at KL, I estimate the locus error to be:
+/- 8nm + a/c altitude x tan(elevation angle)
At 40deg elevation, an a/c at FL350 will be 4.8nm further away from the subsatellite point than measured.
So I estimate the ring error band to be about 21nm wide.
 
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777Jet
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 10:53 am

Quoting YVRLTN (Reply 151):
Quoting 777Jet (Reply 72):
The issue with the cargo scanners not working leads me to believe the cargo might have played a role?

Again, has this ever been proved as the truth?

Has information been released to suggest otherwise - I mean - that the cargo scanners were working and in normal operation that night?

Quoting BackSeater (Reply 167):
The official Indian Ocean search strategy so far has been largely predicated on a steady southbound flight "immediately" after emerging from the Strait of Malacca.

And... because of the supposed 'pings' heard by the TPL in that area.

Looks like the authorities might have jumped the gun. If they shift the search area by a fair bit after the numbers get worked over again it could suggest that a lot of valuable tax payer money has been wasted...
DC10-10/30,MD82/88/90, 717,727,732/3/4/5/7/8/9ER,742/4,752/3,763/ER,772/E/L/3/W,788/9, 306,320,321,332/3,346,359,388
 
Pihero
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 11:23 am

Quoting BackSeater (Reply 172):
No, 7! As I explained at the time, the GES only gets reliable RTDs on a few specific messages (logon/logoff acks).

NO ! 8 !!! You forgot to mention the 16:00:13 on ground at Kuala Lumpur
My friend related to the number of exploitable communications between the plane and the satellite : 47 pages of them... He was correct .
Whether they chose just 8 of these is their privilege ... They probably are the most reliable / accurate... basis for the computation.

Quoting BackSeater (Reply 172):
Based on the standard deviation estimate I computed at KL, I estimate the locus error to be:...

I can(t really see how you can derive a *standard deviation* estimate with just one value. Isn't this a matter of goose and gander ?
If you consider the constraints of logon / log off / ACK, there is only one when the plane was on the ground.

And as everything on this particular subject, it's a matter of trust - or not - and a matter of estimations, the accuracy of which, sorry to say, is highly dependent on the person involved and his assumptions.
Contrail designer
 
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Finn350
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 11:47 am

Quoting BackSeater (Reply 172):
) "When asked how accurate the *loci* could be, he said : their width could be determined to a precision of ten meters, but the problem is assuming an altitude, that would introduce an error of up to 500 meters, maybe a bit more, but I'd be surprised if the lines are determined with a margin of more than a kilometer."
Quoting Pihero (Reply 174):
And as everything on this particular subject, it's a matter of trust - or not - and a matter of estimations, the accuracy of which, sorry to say, is highly dependent on the person involved and his assumptions.

Achieving accuracy of 10 meters in the ping loci width determination would need a BTO timer precision of around 30 ns (that is 0.03 µs). Based on Inmarsat logs, the actual timer precision is around 20 µs.

ATSB states that "an analysis of SATCOM system parameters showed that the accuracy of the rings was ± 10 km."

Source: http://www.atsb.gov.au/publications/...efining-the-search-area-mh370.aspx

There is a discrepancy of three orders of magnitude in the ping ring width determination between the ATSB and Pihero's friend's assessment. I can't see how Pihero's friend's assessment could be the correct one based on the physical characteristics of the system in question, no matter what other assumptions one make.

[Edited 2014-05-28 04:48:17]
 
Backseater
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 12:05 pm

Quoting Pihero (Reply 174):
I can(t really see how you can derive a *standard deviation* estimate with just one value. Isn't this a matter of goose and gander ?

I assumed that the Inmarsat reference fixed terminal operates off 3f1 at its real orbital location. So the motion of the satellite is in both the reference RTD and the a/c RTD, therefore it disappears from the BTO.

At KL, with the a/c at rest, we have a number of R channel messages. They all yielded comparable BTO values around 14820, so we can asume that they form a coherent set and that their statistical distribution is due to the random error in the generation/transmission/measurement process. Using the first 46 values, I found a standard deviation just under 5kms.
When we have a single measurement, I would trust the RTD linked to logon/logoff ack as the AES is essentially idle at that time.

Those are my estimates. You are welcome to propose your own.
 
Backseater
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 12:33 pm

What are the Mdf and Vdf values for a 777-200ER?
I already asked that question yesterday but it went unanswered.
From what I understand, Vdf is to protect the a/c against a short, temporary piloting oversight where Vmo would be exceeded. Since it is supposed to be a very short event as confirmed by the certification methods used to demonstrate that recovery is straightforward, I am guessing that Vdf may be just a little bit over Vmo, maybe 10kts over. Is that true?
 
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seahawk
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 12:49 pm

The big problem is that all calculations become hard, if you consider the option that plane changed speed, changed course or circled between the pings. The plane could have done way more to the north.
 
Pihero
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 12:51 pm

Quoting BackSeater (Reply 176):

Those are my estimates. You are welcome to propose your own.

Hence the reasdon why you dismissed my friend's interpretation of how many contacts were made ?
Just what I thought : a goose and gander situation.

As proposing my own estimates, I haven't and I will not, as I know quite well my limits.
I'll wait for the *official* release of the *official* ping rings by *official* investigators.
I do not have the computational power, nor the final processinhg times on the station, the satellite and the airplane terminal.
Then and only then could we in all honesty try and derive times at loci.

Another aspect that has been totally ignored is the confirmation of the SatPhone call to the aircraft at 23:13:58 Z , without any answer. MH Ops haven't been lying on that .
Contrail designer
 
NAV30
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 1:02 pm

Quoting Finn350 (Reply 165):
Yes, ADS-B went off 1721 Z. Up until that time they can compare the MH370 ADS-B track and the ping rings derived from the satellite data

Apologies if I've got this wrong, Finn350 - but as far as I know, the new thing only produces a 'ping' once an hour? MH370 appears to have been in the air much less than an hour, apparently only about 40 minutes?

So surely it is likely that the new Inmarsat thing didn't produce ANY pings relevant to MH370 before it 'went in'?
 
markalot
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 1:13 pm

It doesn't really matter what it did between pings, it only really matters what happened after the last ping, unless my mind is failing to grasp an important concept, which is certainly possible.

The various pings, which are simply --are you there? yes I am!-- back and forth messages seem to confirm the aircraft is operational.

Measuring the latency of the signals seems to provide 2 positions that the aircraft could be at, and then factoring in satellite drift and Doppler effects seems to indicate that the southern path is the most likely.

The fact that the pings continued for 7.5 hours seems to indicate a rather direct path when guessing the amount of fuel on board and the extra fuel needed to not fly a direct route.

So reviewing all the above, the final ping would seem to indicate a near position of the aircraft before it hit the water.

You can see how many assumptions have to be made, but frankly they are all pretty good assumptions backed up with good explanations as to how the data should read if the southern path was taken. So in fact this IS the simplest explanation as to where the plane wreckage might be found, but the devil in the details is the error factor in the final location. I think it's pretty large and it's worthwhile going over all the data and trying to further narrow down the final position.
M a r k
 
Pihero
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 1:47 pm

Quoting BackSeater (Reply 177):
I am guessing that Vdf may be just a little bit over Vmo, maybe 10kts over. Is that true?

Vdf / Mdf are the in-flight demonstrated diving CAS and Mach for a given airplane : They require quite a lengthy purposeful powered dive in order to be achieved : let's say that as a ballpark , we are talking about Vdf ~VMO + 25 or 30 kt and Mdf ~ MMO + . 09, so for the 772, Vdf ~ 355 to 360 kt and Mdf ~ .96 M. (Those are what the *flutter tests* are about )
But we're talking about a FBW aircraft with high speed pitch protection : at VMO / MMO, no more nose-down trim and you'd have to try and fight very hard to get beyond. It is certainly not a long term proposal.
( If you're looking for that aspect of the 772 speeds for your High / Low / High scenario, I'm afraid it's another impossibility, with or without the autopilot ).
Contrail designer
 
Backseater
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 2:04 pm

Quoting Finn350 (Reply 168):
Regarding the flight path published in conjuction with the preliminary report: it might be that the flight paths in itself don't matter, it is only the possible end points on the final arc that are really meaningful. Even if the flight path crosses north of Sumatra, it might be one of several alternatives which will reach the same point on the final arc using the same constraints (average ground speed, available fuel).

Allow me to say that I really don't follow you on this one!
Break the preliminary report track points into three sets:
- the 18:28 point is in the first set and stays stationary because it is pretty much tied to the air defense point at 18:22
- the 19:41 is in the second set and can be moved around rather easily because it is still close to 18:28 for a 73min flight and very close to the 20:41 for a 60min flight:
- the remainder of the track points starting with 20:41 are in the third set. We can now rotate that third set around the average subsatellite point for that set. That is of course just an approximation because we should recompute the location of each point on each track after a rotation around its own subsatellite point taking into account the oblateness of the earth. But you get the idea. During that rotation, note that the BTO values remain unchanged, only the BFO values are slightly changed because both the a/c to 3F1 and a/c to sat at nominal position vectors have changed. Using a counter clockwise rotation the final high probability search area can be moved north almost all the way to Java, with the third set conforming nicely to the curvature of the Sumatra-Java coastline. For a given rotation, there are still many ways to fly from 18:28 to some point at 19:41 and easily link up with 20:41.

Obviously such a scheme is plausible only in connection with an a/c piloted by some entity.
 
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fotoflyer71
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 2:07 pm

Quoting NAV30 (Reply 183):
Please provide any evidence you have to hand to prove that MH370 was in the air for an hour? It went off radar, and its communications went down, long before that?

Perhaps this analogy will help you understand NAV30.

You're a pilot right? Let's say you're in a C172 flying up the east coast of Florida at 2,500'. Your alternator goes tits up, but hey it's day VFR, so you turn off all your electrical equipment to conserve battery in order to deploy flaps and make radio calls prior to landing. You decide to proceed with your flight, you've got a couple of hours to go, it's day VFR, and you're confident you can avoid any airspace that you're not permitted to fly through with your radios and transponder turned off.

In your pocket is your cellphone. Like the majority of US GA pilots, you don't bother turning it off, or putting it in airplane mode - damn the FCC. While you're flying along, at 2,500', your phone is searching for cell towers to associate with - sometimes it successfully registers with a tower, sometimes not. The point is you are leaving a trail along your route of flight. The data logged by the cell towers proves, beyond a shadow of a doubt, that YOUR CELLPHONE was definitively tracked along that route. Two hours later you get to the private airpark you were destined for, land safely, and have a nice vacation. Where would the authorities go looking for you if they were concerned? Initially, to the place where you lost comms, sure. However once they found the cellphone data, they would switch to the last cellphone tower your phone checked in with. Right?

Your insistence that MH370 could have crashed 40mins after takeoff ignores the breadcrumb trail that the SATCOM equipment aboard MH370 was leaving as it flew along with all its other comm stuff turned off or inoperable. Something with MH370's unique ID was communicating via satellite for 7.5 hours, and it's location was moving. Crash in water = no satellite communication = no breadcrumbs. Make sense?
Try to learn from the mistakes of others. You won't live long enough to make all of them yourself.
 
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 2:10 pm

Quoting jox (Reply 185):
It's communication went down EXCEPT for the Inmarsat terminal. That box ACTIVELY responded to signals it received from the outside world!

I'm sure that you'll agree, jox, that the Inmarsat stuff is new and experimental?

You appear to agree that all the OTHER (more established) systems 'fell silent' during the period in question? And that there is no doubt about the aeroplane 'losing contact'?

So we have to depend solely on the 'new-fangled' Inmarsat?

Don't fancy that, myself. In any case, what WAS Inmarsat actually showing at that time? I've googled a bit, but can't find anything 'solid' yet?
 
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 2:14 pm

Quoting NAV30 (Reply 188):
I'm sure that you'll agree, jox, that the Inmarsat stuff is new and experimental?

Inmarsat isn't new and experimental! The company was founded 1979. And the particular equipment used is some of their older (i.e. well proven) stuff, that has been in operation since 2008, I think.
 
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 2:21 pm

Quoting NAV30 (Reply 188):
You appear to agree that all the OTHER (more established) systems 'fell silent' during the period in question? And that there is no doubt about the aeroplane 'losing contact'?

So we have to depend solely on the 'new-fangled' Inmarsat?

dude, what is your fascination with the apostrophes? do you speak like 'that' in real life????

a question for pihero...

regading your fire theory- do you think an impact from that gentle descent would rip the plane apart? and if so, what could explain the debris conundrum? and would there not have been a fire from the remaining jet fuel on board?
trying to stop my gaseous viscosity go liquid
 
NAV30
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 2:21 pm

OK, jox, and everyone else. 'Fair go,' I've had my say and received a fair hearing.

But the aeroplane still 'went missing.'

So what do YOU think happened?

[Edited 2014-05-28 07:38:23]
 
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 2:46 pm

Quoting Finn350 (Reply 165):
Yes, ADS-B went off 1721 Z. Up until that time they can compare the MH370 ADS-B track and the ping rings derived from the satellite data, and after that time they can compare all the other planes still tracked by ADS-B and their corresponding satellite data (and that is precisely what Inmarsat & others have done in order to verify their analysis).

Finn, you've been compiling a lot of information: Do you have the ADS-B track, preferably a list of lat/longs with times, or know where one could be obtained?
 
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 2:52 pm

Quoting Pihero (Reply 174):
NO ! 8 !!!

There's 92 of 'em actually...
 
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 2:56 pm

Quoting liquidair (Reply 190):

regading your fire theory- do you think an impact from that gentle descent would rip the plane apart? and if so, what could explain the debris conundrum? and would there not have been a fire from the remaining jet fuel on board?

It's not a fire theory ; It's an electrical short problem. I've given enough examples of electrical problems for that. Contactors or glowing contacts are my main concerns.
Secondly, about the impact : I think there are good chances that the kinetic energy dissipation was long enough to leave the aircraft fairly intact : The engines will be ripped off the wings, a succession of ricochets on the swells ( the aircraft was roughly parallel to them ) would slow it down enough and the final nose dive would be ending it all, but providing a compression stress to the whole fuselage structure to leave it whole and unbroken... but badly creased in the front end.
It's a possibility... which checks with the lack of found debris.
As for fire from the remaining fuel, as there would niot be any breakage of any importance, there won't be any.

But it's a theory and a possibility. Just that.
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 2:59 pm

Quoting Pihero (Reply 184):
( If you're looking for that aspect of the 772 speeds for your High / Low / High scenario, I'm afraid it's another impossibility, with or without the autopilot ).

Gee, how did you manage to read my mind?   
Seriously, thanks for the answer. CAS=360kts at 15,000ft => TAS std=440kts(?) plus temp comp + tail wind(?) => GS too low for my purpose. Obviously at 10,000ft, things are much worse with TAS about 50kts lower.

What I am after is no longer a radar evading path from IGARI to PEN as it is not clear whether there were even any radars watching that sector at that time. But I am really concerned about the "non existing" radar plot west of Penang because except for my climb scenario west of Penang, I have yet to see an explanation for the intermittent radar returns they got if the a/c was at cruise altitude, even down to FL300. And speeds on that flight segment appear to be fairly high (varying from maybe 440 to 510kts). To me that is a real conundrum.

I am guessing that Vmo must always be very conservative in order to protect the a/c under all circumstances, including very turbulent air. Unlike Mmo, Vmo deals primarily with aerodynamic stress that can quickly become dangerous at high speed at low altitudes. But what if the air happens to be very still that night? No wind.No turbulence. Could a non-pliot flying that a/c probably with zero knowledge of Vmo greatly exceed it after a fast descent? Apparently the three airplanes involved in the 9/11 disaster exhibited GS from 430 to 510kts at very low altitudes.
 
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 2:59 pm

Quoting BackSeater (Reply 167):
What I am driving at is that 9M-MRO may not have been so eager to reach the Diamantine trench after all. From IGARI to the air defense point at 18:22, the path was IMO designed to keep looking friendly to Malaysia and not venture in either the Indonesian or Thai FIR while flying northwest bound up the Strait of Malacca. The a/c was flying directly away from Malaysia/Butterworth AB (=friendly) and slowly but surely getting further away from both Indonesia and Thailand (=noalarm).

Yes, the overflight of Indonesia seems unlikely. If he wanted to overfly Indonesia, there would have been no turn at Penang, and he would have just cut across Sumatra. For whatever reason, he chose to avoid Indonesian airspace by turning up the straight. We do not need to know why, but it could have been any number of things: desire to avoid radar, surface to air missiles, scrambled fighter jets, just mere whim. Bottom line is if he avoided the middle of Sumatra, he would have avoided northern Sumatra. Combine that with the fact that it was not in fact detected by Indonesia, then he must have cut over north of the island, most likely along air route P627 (NILAM POVUS), before turning south.
 
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777Jet
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 3:04 pm

Quoting Pihero (Reply 185):
Secondly, about the impact : I think there are good chances that the kinetic energy dissipation was long enough to leave the aircraft fairly intact : The engines will be ripped off the wings, a succession of ricochets on the swells ( the aircraft was roughly parallel to them ) would slow it down enough and the final nose dive would be ending it all, but providing a compression stress to the whole fuselage structure to leave it whole and unbroken... but badly creased in the front end.
It's a possibility... which checks with the lack of found debris.

That I agree with... However, anybody who mentioned that idea in the first 60 or so threads were basically flamed  

How times change...
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 3:28 pm

Quoting Pihero (Reply 170):
As proposing my own estimates, I haven't and I will not, as I know quite well my limits.
I'll wait for the *official* release of the *official* ping rings by *official* investigators.
I do not have the computational power, nor the final processinhg times on the station, the satellite and the airplane terminal.
Quoting Pihero:
As proposing my own estimates, I haven't and I will not, as I know quite well my limits.
I'll wait for the *official* release of the *official* ping rings by *official* investigators.
I do not have the computational power, nor the final processinhg times on the station, the satellite and the airplane terminal.
Then and only then could we in all honesty try and derive times at loci.

It's not that hard--it doesn't take a lot of processing power. Also, the final processing times are listed down to the millisecond. This is how you do it:

1. For a known location, measure the distance from the a/c to the sat (AS), and from the sat to Perth (PS). Since it's a 4-way trip for the signal total travel time is (2*PS + 2*AS)/c (where c is the speed of light).

2. Obtain a correlation constant K as follows:

K = (2*PS + 2*AS)/c - BTO.

3. With K in hand, you can calculate ping rings for unknown positions as follows: measure distance from Perth to sat (PS); calculate the 4-way travel time (K + BTO); subtract the Perth compenent; divide by 2

1-way travel time = [(K + BTO) - (2*PS/c)] / 2

4. Take this 1-way travel time from the a/c to the sat; multiply by c, that gives you the distance from the a/c to the sat (AS). From there, you can use principles of geometry to get the ping ring or loci radius to the subsatellite point.

5. An alternate approach might be to empirically measure the AS distances for all known positions at handshake times, plot these against the BTO times, do a linear regression on those data points, and you'll derive a formula of the form AS = (a + b * BTO) / c that can be used to get the a/c to sat distance hence the ping rings.
 
liquidair
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 3:33 pm

Quoting Pihero (Reply 185):

thank you for your reply... and correction- yes, electrical short not fire, my bad.

such a scenario does tick all the boxes i guess... had anyone in the back been alive perhaps they could have survived the impact?
trying to stop my gaseous viscosity go liquid
 
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777Jet
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 3:47 pm

Quoting liquidair (Reply 190):
had anyone in the back been alive perhaps they could have survived the impact?

Of course. Moreover, if somebody like Bear Grylls was seated in the back I would still give them a very, very slim chance of even being alive and floating around in a life raft... You know some of the things he does to stay alive...
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dtw2hyd
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 4:14 pm

Bluefin-21 on US NAVY contract done with its mission in Indian Ocean. Do Australia or Malaysia have any plans going forward?
 
sipadan
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 4:22 pm

Quoting dtw2hyd (Reply 192):
Bluefin-21 on US NAVY contract done with its mission in Indian Ocean. Do Australia or Malaysia have any plans going forward?

yeah...to leave it all behind.
 
Pihero
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 5:33 pm

Quoting 777Jet (Reply 188):
However, anybody who mentioned that idea in the first 60 or so threads were basically flamed

I gave that idea a few weeks ago.
Never ever ever give up on your own assumptions if you think they are worth considering.
After all, in different fields we are just into conjectures.
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JHwk
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 5:42 pm

Quoting YoungMans (Reply 151):

You COULD falsify ping data easily to add delay, but you could not reduce it. To make it work, you would need to be in the same spot beam as the aircraft, and know that the pings are being sent and that the aircraft is not going to try and send responses. In theory it wouldn't be that hard.

The problem with the falsification theory though is that it has to be done real-time, in anticipation, and coordinated with whatever incapacitated the aircraft.
 
nupogodi
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 5:48 pm

Quoting JHwk (Reply 195):
In theory it wouldn't be that hard.

What qualifies you to make this statement?

Because it's incorrect.
A man must know how to look before he can hope to see.
 
mandala499
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 6:41 pm

Quoting YVRLTN (Reply 142):
That is interesting, it may be really helpful if you could find it.

I've been looking for it since that saturday morning...

Quoting sipadan (Reply 155):
The technical aspects of 9/11 really never surpassed flight sim training and crude flying (although the actual skill level of the 'pilots' is something that is still debated today--not that it matters).

So, after all these years finally someone in a.net agrees with me on this!   

Quoting sipadan (Reply 155):
So my attitude towards Inmarsat all along has been that they are the de facto face of US Intel (or British).

You said it, not me...

Quoting BackSeater (Reply 158):
That is interesting, particularly if you want to be seen by radar on your way to nowhere. I am not talling about the secondary radar at Banda Aceh that the a/c probably overflew. Around the northern tip of Sumatra there are two primary radars: one near Sabang on Pulau We island (THomson TRS 2215 D?), the other near Lhokseumawe (Thomson TRS 2215?). Apparently the one in Sabang is tasked with looking eastward towards the Strait of Malacca whereas Lhokseumawe looks westward towards the Indian Ocean area. Therefore, according to the Prelim the a/c flew right in between the two radars and should have been painted by both.

Sabang/We would be the one looking towards northeast to southwest, this would be the one looking to the Indian ocean. Lhokseumawe is the one for the strait of Malacca. It's not in a good position to observe the Indian Ocean from there.

Quoting BackSeater (Reply 158):
Pumono also added that "the Indonesian military radar placed in the country's western-most city of Sabang is strong. It did not detect an airplane flying over Indonesian territory".

Which means either of the two:
1. Our radar wasn't switched on at the time, therefore we didn't detect it.
2. We detected it, but the aircraft didn't come to within 12nm from our coastline hence it does not count as flying over our territory (despite being in our FIR).
3. It was switched on but no one was looking at the screen and the recorder wasn't on.

Quoting BackSeater (Reply 158):
I am suggesting that after exiting the Strait of Malacca, 9M-MRO may have loitered for a while (N, NE, N, NW, W, SW, S, SE), at slow speed (max endurance?), possibly waiting for some event (via HF?), meeting the early ping rings by accident, moving eventually to a southbound then southeast bound route patterned after the western coast of Sumatra and then Java. The a/c could have penetrated the Indonesian FIR without any risk of challenge provided its altitude remained below the radar horizon for any radar that might be along the coastline.

Disregarding the loitering, I must say, finally, someone else also sees this! I do suspect that it might have gone slower and went closer to Sumatra and Java.
And the aircraft can continue west of Sumatra down to the southeast towards Java and no primary radar would have detected it even on cruise altitude.

Quoting BackSeater (Reply 177):
For a given rotation, there are still many ways to fly from 18:28 to some point at 19:41 and easily link up with 20:41.

Obviously such a scheme is plausible only in connection with an a/c piloted by some entity.

Or a long shallow turn?

Quoting Pihero (Reply 185):
Secondly, about the impact : I think there are good chances that the kinetic energy dissipation was long enough to leave the aircraft fairly intact : The engines will be ripped off the wings, a succession of ricochets on the swells ( the aircraft was roughly parallel to them ) would slow it down enough and the final nose dive would be ending it all, but providing a compression stress to the whole fuselage structure to leave it whole and unbroken... but badly creased in the front end.
It's a possibility... which checks with the lack of found debris.
As for fire from the remaining fuel, as there would niot be any breakage of any importance, there won't be any.

It doesn't have to be intact and unbroken for it to leave no debris. It could have had significant damage below the cabin floor and still not have any floating debris... but yes... those are just nasty details of a theory.

Quoting WarrenPlatts (Reply 187):
We do not need to know why, but it could have been any number of things: desire to avoid radar, surface to air missiles, scrambled fighter jets, just mere whim. Bottom line is if he avoided the middle of Sumatra, he would have avoided northern Sumatra.

A pilot familiar with the area would know the following:
1. In that area, we have no fighters capable of intercepting airliners cruising normally at night beyond 100NM from Pekanbaru, where fighters are based.
2. Medan has no fighters based there, neither does Banda Aceh, or Sabang, etc. Anyone flying to Medan in the past 10 years and up to 12 months ago would know that...
3. The radar at Medan is switched off at night almost all the bloody time, either intentionally, or there's a power cut.
4. Surface to air missiles? No, we don't have any over there in peacetime!

---

Quoting NAV30 (Reply 149):
So, only about 40 minutes after take-off, all the OTHER methods of tracking the aeroplane went off-air. Leaving only Inmarsat to track the aeroplane (as far as I know, only in the shape of hourly 'pings')?

and:

Quoting NAV30 (Reply 171):
Apologies if I've got this wrong, Finn350 - but as far as I know, the new thing only produces a 'ping' once an hour? MH370 appears to have been in the air much less than an hour, apparently only about 40 minutes?

OK, if you do not want to look at the evidence provided, please understand the following:
1. The Inmarsat pings are NOT hourly. If there are NO DATA transmitted to or from the aircraft, then it would ping for about every hour.
2. The "ping roughly every hour" was for after the aircraft finally went missing from military radar going north west over the straits of Malacca...

Quoting NAV30 (Reply 149):
I think there is a distinct possibility that MH370 ended up in the sea at that point.

Mate, sorry, simply... NO! Get that into your vegemite overdosed head if you may...
They searched the area where the aircraft disappeared from secondary radar... and for quite some distance to the north east and found nothing... then they got data from the satellite communications that it was flying for another 7 hours... so no... it didn't end up in the sea at that point.

Quoting NAV30 (Reply 179):
that the Inmarsat stuff is new and experimental?

No. The Inmarsat equipment on the aircraft is quite old. It is for the Inmarsat-3 network which has been used in aviation for over 10 years. The aircraft has had this installed either in the factory or retrofitted it later.
It is NOT experimental, and it is certified for airborne use, and it is also certified for airborne safety services use.

The newer Inmarsat-4 service has been on since 2007, and it is also no longer new and no longer experimental.
When losing situational awareness, pray Cumulus Granitus isn't nearby !
 
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 7:58 pm

Quoting 777Jet (Reply 191):
Moreover, if somebody like Bear Grylls was seated in the back I would still give them a very, very slim chance of even being alive and floating around in a life raft

Wonder what that guy on the life raft would say if he were to be rescued and got a chance to read these threads.

Quoting mandala499 (Reply 197):
then they got data from the satellite communications that it was flying for another 7 hours... so no... it didn't end up in the sea at that point.

In your opinion is the Inmarsat satellite data and the subsequent analysis by them solid enough to rule out the following

1) a track due west towards Africa (flying South of Srilanka in a westerly direction)?
2) a track east of Malaysia out into the Pacific Ocean? Would have had to fly over some land though before being over the open Pacific (at least over the southern tip of Philippines without detection).

What i am getting at in other words is, in your opinion, how reliable is the conclusion that the aircraft ended up somewhere in the Southern Indian Ocean off Perth based on Inmarsat's analysis OR are the search authorities looking totally in the wrong place?

[Edited 2014-05-28 12:59:27]
 
Backseater
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 9:05 pm

Quoting mandala499 (Reply 197):
Sabang/We would be the one looking towards northeast to southwest, this would be the one looking to the Indian ocean. Lhokseumawe is the one for the strait of Malacca. It's not in a good position to observe the Indian Ocean from there

Of course you are quite right. I had followed a comment by a mil type blogger but that was a mistake. I finally found the Sabang primary radar. With a 360deg unobstructed view, it is at about 1,500ft above sea level thus gaining close to 50nm in range capability. If that radar was operating that night, 9M-MRO should have been detected even if flying away from Sumatra towards the Andaman islands (unless maybe flying below 3,000ft).

Too bad we cannot reliably find out which radars were powered up that fateful night and if so what they detected. If we could, I believe we might be able to discriminate between piloted or non piloted flight.
 
WarrenPlatts
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 9:32 pm

  

Quote:
Quoting Pihero: I'll wait for the *official* release of the *official* ping rings by *official* investigators.

You could be waiting a long time sir. Meanwhile, the *unofficial* release of the *unofficial* ping rings by the *unofficial* investigators has just been released.

https://www.dropbox.com/sh/g2qcyqzwk7m2xcr/AACR-KSWHH0XgREETDNJk10Wa

It contains:

Quoting Duncan Steel:
All BTO values;
All ground station to satellite distances;
All aircraft to satellite distances; and
All propagation time delays between the aircraft and the satellite
… for each of the 92 times at which there was an R-Channel ping completed.

The relevant file is called BTO_92.xslx
 
LH707330
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RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 10:13 pm

Quoting moderators (Reply 25):
But we ask you to respect everybodys opinion in here. Try to stay calm and don't start any name calling in here.

Thanks, we needed this.

Quoting Finn350 (Reply 146):
Don't worry. He is probably recovering from the realization what the most likely scenario for the disappeareance of MH370 is (and to lesser extent that his pet theory 'IGARI direct to north of Sumatra' is ready for vertical archiving based on the ATSB publication).

The direct path may be vertically archivable, but the tech problem not so much. If the track looks like a turn to Penang for a landing and something went awry, then a mechanical hypothesis is still plausible. Moreover, if an irrefutable smoking gun shows up, I will certainly admit that my mechanical idea was wrong, and I reckon Pihero would too. To be clear, I'm not taking the position that it was mechanical over foul play, I'm simply trying to tease out possible mechanical theories because the foul play ones don't require much imagination. At this stage, I think both options are plausible, and we don't have enough to take a strong stance in support of either.

Quoting YoungMans (Reply 147):
The data from this particular satellite has 'always' contained a small error.

In which case we could punch in offsets or test against other planes to correct for the error against known values and revise the search area. My guess is that this was done when they tested the ping ranging with the other aircraft.

Quoting YoungMans (Reply 147):
The data from the satellite has been deliberately falsified.

It's possible, but qui bono? Any time one suggests coverups or other nefarity, it's important to run it through Occam's razor. Does the theory make the explanation more plausible, or does it require more premises to explain the data? Keep Hanlon's Razor in mind too: Never attribute to malice that which is adequately explained by stupidity (or incompetence). One can come up with plenty of explanations for how various entities are behaving, the simplest of which is IMHO "these guys were unprepared for something of this magnitude."

Quoting YoungMans (Reply 147):
The data may not have been just falsified but was completely fabricated, concocted; this could have been to an extent that not even the satellite company would have noticed anything wrong, at least not initially.

Again, qui bono?

Quoting NAV30 (Reply 149):
I think there is a distinct possibility that MH370 ended up in the sea at that point. How Inmarsat apparently went on 'pinging' a possible western and/or southern course, I don't know. But all OTHER contact with the aeroplane - and the crew - ended at that time? And the flight crew never checked in with Vietnam?

A better way to phrase it is "what could knock out all comms except the satcom?" Between
a) "someone deliberately switched them all off and didn't know about the pings,"
b) "someone pulled CBs after an electrical problem," and
c) "the plane crashed but somehow the satcom survived,"
c is by far the least plausible. If you can come up with a good, plausible reason why the satcom antenna would ping for 7 hours after the plane crashed, let's hear it. Otherwise, let's move that idea to the round file.
 
bcworld
Posts: 139
Joined: Thu May 19, 2011 1:28 am

RE: MH Malaysia Airlines B772 Missing Enroute KUL-PEK Part 64

Wed May 28, 2014 11:14 pm

http://edition.cnn.com/2014/05/28/wo...lines-pinging/index.html?hpt=hp_t1

Navy official: Pings not thought to be from Flight 370's black boxes

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