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-   -   Malaysian Airlines MH370 contact lost (https://www.pprune.org/rumours-news/535538-malaysian-airlines-mh370-contact-lost.html)

AerocatS2A 17th Mar 2014 14:02

Overthewing, all of the TCAS units I've played with have been integrated with the transponder. Turn the transponder off and you don't have a TCAS, at all, not for receiving or transmitting. Think of TCAS as a type of transponder rather than a separate system.

macilrae 17th Mar 2014 14:03

Professional Experts
 
On the subject of the "experts" who are continually trotted out by the likes of CNN and BBC - many of these folks are Professional Experts and they have spent a working lifetime polishing their credentials, rather than actually contributing to their field. They sit on the right committees, they acquire the right letters after their names and as 'talking heads' they sound super-authoritative - they excel in self-promotion. In fact you can find these people in every profession. The real experts, who can give the most insightful answers, are seldom seen - partly because they prefer to be doing real stuff - and maybe also because they are lousy presenters and shun the limelight.

xyze 17th Mar 2014 14:06

Skytrax:

At the risk of pointing out the obvious, they HAVE gotten away with the cargo.

Whether that was their aim is anyone's guess!

SeenItAll 17th Mar 2014 14:06

Moderators: Since it seems impossible to completely shut down this thread and the repetitive uninformed drivel that characterizes the majority of the posts, I have an alternative suggestion: split this thread into five separate threads.
  • One thread will be for posts suggesting that terrorists having hijacked the plane to land it or to plunder its cargo and then relaunch the plane as a bomb.
  • A second thread will be for the pilot suicide or "crash the plane where it will never be found" theory.
  • A third will be for the mechanical malfunction theory.
  • A fourth thread will be for a discussion of Search and Rescue operations.
  • And a final thread will be for posters who have not adequately read the previous posts but who want to pose a question to those that have.
By doing this, it will allow those who are absolutely convinced of terrorism not to be burdened by reading analysis about suicide or malfunctions; those who can see no logic in terrorism not to be burdened by endless X-Files speculation about cargo and Flying Dutchman relaunches; those who are sure the plane malfunctioned not to waste time discussing pilot or terrorist actions; those who just want to figure out where the plane is now not to listen to the previous three groups; and those that think they are on to something but don't want to the the research themselves to query from those that have.

This would save all of us a great deal of reading time. Thanks for listening.

currawong 17th Mar 2014 14:06

On the balance of probability -

the northern arc is mainly over China...

the pax are mainly from China...

the cargo is mainly mangosteens...

therefore -

no, you work it out for yourselves.

Thoughts to the families of the pax and crew at this difficult time.

I remain optimistic.

(And all that without lighting up anyone's radar screen, across several countries. Outstanding.)

litinoveweedle 17th Mar 2014 14:07

Quote:

If on the other hand the assumptions are not for example the ping came from another source say SQ68 bound for Barcelona, then that line of enquiry ends right there.
IMHO pings are probably TDMA channel sync or frequency sync bursts. This means, that inside of data, there could be probably two low level identifiers.
1. the HW identifier (something like serial number of your phone (IMEI) or MAC address of you computer)
2. artificial identifier of the connection (which could be correlated with connection information stored previously in time of connection handshake)

There would be no data inside of these burst, as these serve only to SATCOM to keep connection to satellite synced and alive,

I would say that forging data connection on TDMA is possible and it is used for example to intercept GSM connections (man in the middle attack), but this process is definitely not trivial.

I would say, that probability, that these pings were mistakenly from another plane or forged to pretend to be from HM370, is really low.

owenshaw 17th Mar 2014 14:08

Sorry if this has already been mentioned...

The 40deg contour heading north covers the Xinjiang Province/ East Turkestan. (political unrest in the area)
According to Wikipedia an East Turkestan flag was found at the Kunming Massacre.
Will any of this end up being related?

ana1936 17th Mar 2014 14:09

some of us, maybe myself included, have been a but loose with the term ping perhaps.

Just to clarify this a little.

My understanding is that the satellites in the INMARSAT network which deal with ACARS check on the presence of their registered aircraft every hour by initiating a ping operation. This involves the satellite asking to see if a particular aircraft will answer. Only the specified aircraft will answer. And it will only answer if its engines are operating and it hears the satellite request.

Token Bird 17th Mar 2014 14:09

Quote:

Except (I understand) they have primary radar "confirmation" of a north-easterly course after the westbound one (ie IGARI - VAMPI - GIVAL ....)
That was what I was trying to figure out. I recall reading that days ago but was unsure as to where that info had come from, and if it was primary radar, was it later confirmed by the Inmarsat ping data. Since they have only released info about the final ping it's not possible to tell.

I'm going to trawl back through this thread and see if I can find the reference regarding the theory they flew IGARI-VAMPI-GIVAL.

FlyingOfficerKite 17th Mar 2014 14:09

Quote:

I wonder if the aircraft and passengers landed somewhere else and was refueled to await "further orders"??
Assuming the aircraft is intact and on the ground, what would be the purpose of this silence by the hijackers/sky pirates?

1. Secret negotiations already in progress?
2. Stealing of valuable cargo/VIP hostage?
3. Time to disperse the pax and crew with a view to hostage negotiations individually and/or
4. Preparing the aircraft to be used as a 'flying bomb' at some future date?

All mentioned before, but if the aircraft has landed safely what other explanation could there be?

If any or all of these scenarios are acted out a new dark age of aviation will be upon us.

SgtBundy 17th Mar 2014 14:13

Quote:

If something remotely viable and simple to implement could have been done, it would have been done by now. The Tomnod marketing excercise was rolled out in a couple of days.

Fact of the matter is that implementing and debugging algorithms takes some time and effort... and therefore manpower and money.

Add onto that you're expecting satellite companies to retask their satellites for a vast area of fresh imagery..... who's going to pay for that on top of the development manpower for your magic algorithm.

Your optimism and faith in existing "simple algorithms" is commendable, but that's all it is.
Tomnod was setup in the past for some Typhoon Haiyan and they were able to source/request fresh satellite passes from I believe the day it disappeared, seeing as they own the satellites. Their current effort is re-using an existing platform for a fresh task. Marketing maybe, but hardly a futile effort when at the time they were looking for a crash site, they had the satellites to do it and the technology platform to deliver it.

No doubt to yield good results it takes time to tune and improve the methods. All I am saying is that at a high level the effort to discount large sections of ocean appears trivial, and as I said I would expect this is probably something they are smart enough to have done already. If you are talking about recognizing an aircraft or specific aircraft from this imagery, yes that would be a significant effort.

Elastic infrastructure is easily available reasonably cheaply so I don't think some of what I suggested is that far fetched.

Alloyboobtube 17th Mar 2014 14:14

Lack of signal means it could also be in 20,000 ft of water.
Could it have been landed gently in the Indian Ocean with outflow valves open and a gentle sink to the bottom intact..

The Bullwinkle 17th Mar 2014 14:15

Quote:

One thread will be for posts suggesting that terrorists having hijacked the plane to land it or to plunder its cargo and then relaunch the plane as a bomb.
A second thread will be for the pilot suicide or "crash the plane where it will never be found" theory.
A third will be for the mechanical malfunction theory.
A fourth thread will be for a discussion of Search and Rescue operations.
And a final thread will be for posters who have not adequately read the previous posts but who want to pose a question to those that have.
How about a sixth thread for those who wish to wait till the aircraft is found and the real answer is discovered?

Just a thought!

geneman 17th Mar 2014 14:16

Identification of ping origin.
 
Simple question:
Does a ping transmitted from an aircraft and received by a geostationary satellite UNEQUIVOCALLY identify the aircraft, in the absence of any other data?

(Sorry if this has already been covered...but I couldn't find an answer to this fundamental question.)

SLFplatine 17th Mar 2014 14:17

I think we can really forget the 'Uighur terrorist' angle -their ops expertise extends no further than hand held knives and crude VBIEDs that generally do not work as intended.

rgbrock1 17th Mar 2014 14:24

Nortwest Orient Airlines flight 2501 was a DC-4 aircraft which was flying between NYC and Seattle, WA in June 1950, carrying 55 passengers and 3 crew members.

Last contact with the aircraft was when it was flying over Lake Michigan at 3,000 ft. She abruptly disappeared from radar and the presumed wreckage was never located. This despite the use of sonar and dragging the bottom of Lake Michigan with trawlers.

Even with modern technology in use (side-scan sonor, etc) the presumed wreckage was never found.

Lord Spandex Masher 17th Mar 2014 14:24

Quote:

Originally Posted by overthewing (Post 8383145)
And I don't think TCAS on /transponder off makes you visible to other a/c? Does it?

Like others have said you can't have one without the other. So for you to be able to track an other aircraft using TCAS the other aircraft will be able to see you, as will all the other SSR receivers in the area.

Buy like you said, I'd would be pot luck as to which aircraft you came across, there's no info from TCAS except height and to visually identify the type and the airline you need to be within about ten miles at the most.

oldoberon 17th Mar 2014 14:25

Quote:

Originally Posted by Xeptu (Post 8383141)
If SQ68 had no message to send, the acars would remain silent and the satcom would ping. There is definitely no identifiable data in a ping

EDIT: If data is to be sent either way then it will be preceded by a connection request (handshake) and yes that has identifiable date of course, I understood we were dealing with a ping.

As you have only just joined the thread let me bring you up to speed as I understand it.

yes they are pings

MAS did not subscribe to acars on satcom

MAS adverts say 1st class has sat phones

PAx, engineers etc say this aircraft does not have sat phones

It does not use the newer satcom aerials which were subject to AD for corrosion but has the older two aerials.

"established" opinion and understanding over the read says that it was obviously on and pings include the unique airframe code as that is embedded into all data transmitting devices (If that is not the case there will be loads of aircraft in a similar config where satcom keeps pinging with unidentified sources.)

Not being rude can you tell us what your filed is to make your statement so emphatically, if it is sat comms pls read my post #5173 page 259

oldoberon 17th Mar 2014 14:35

Quote:

Originally Posted by skytrax (Post 8383157)
Guys, forget about robbery scenarios and all that nonsense. Forget about the cargo, tones of gold etc that might have been on board.
Nobody in the right mind and familiar with the aviation field would try something like this because you cannnot get away with something like this. Too complicated to put in practise such thing.

I personally belive this was planned but for completly other reasons which are yet to be revealed. Hopefully we will get to know one day. Without finding the plane and black boxes information is very limited.

in the 60's we would have said you can't rob a train carrying 2m but Biggsy and co did, yes it was less complicated but had you hypothesised that in the 60's the reaction would be the same as yours. WHERE THERE IS A WILL THERE IS A WAY

However I agree your last sentence.

ana1936 17th Mar 2014 14:35

Since the pings are initiiated by the satellite the idea of the pings being from the wong aircraft need some one else to want to pretend to be MH370 for six hours.


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