[WindRide]

Originally Posted by one-77

... I wonder if India would pick up a rogue plane flying over the subcontinent...

N, N-E and N-W would definitely be alert 24x7. Every other direction could be assumed to be porous.

And oh, conspiracy-theorists are pointing at a possible landing on Diego Garcia. Even if there was no landing there, radars on that island would definitely have tracked the plane. So US is aware....

[Jeroen]

I have seen various questions on the mobile phone on this plane and how they could be traced etc.

I wrote the below on an aviation forum. Hopefully it provides some insights into Mobile Phone and Mobile Network capabilites. I have tried not to use any real technical jargon.

Couple of things on the various mobile phone myths surrounding this tragic incident.

As pointed out earlier, the fact that you hear a ring tone, doesn't necessarily mean the mobile phone on the other end is ringing. It could be just the network. People still sort of think as a mobile call is a sort of one to one connection. It is, of course, but through a complex maze of routers, switches, fiber, microwave connections and various other radio frequencies. It all zero's and one's.

It is technically feasible or possible to be in range of a mobile network at say 35.000 feet. It is just not very likely. Mobile Network Operators want to provide radio coverage on the ground, not in the air. So typically your antenna's are pointing downwards. By the way, just because you see the antenna's mounted on the towers vertical doesn't mean they radiated evenly along a horizontal axes. We use electronic tilt. Radiowaves being radio waves and propagation will mean you get coverage in various spots, including at 35000 feet. A lot will depend on the technology and the frequency used. The higher the frequency (e.g. 1800-2300 band) the less coverage you get. 800-900Mhz will reach much further. And the old 450Mhz systems such as NMT450 had an incredible range.

When I was based in the USA and piloting my own planes, such as Cessna, Cirrus, Diamond I did some testing. I think I wrote about it on this forum as well. Cant remember the exact numbers anymore. But in general you would not get voice or data coverage above 10-12000 feet. That doesn't mean it can't happen.

Mobile network are planned so that coverage is provided through contagious "cells". Once your mobile phone is properly identified in the mobile network the network knows in which cell you reside. It will also know which are the neighboring cells. As you move toward the edges of your cell, radio coverage will weaken and the system will decide to hand you over to the next cell. This all happens without us users knowing, its a seamless handover, providing the system is well optimized.

These cells are planned out on the ground, based on frequency planning, power output etc. Obviously, some of that radio energy will make it all the way up to 35.000 feet. However, at that altitude the same cells might not be present, so the system doesn't know to which cell you need be handed over. In such a case you would experience a dropped call and or data session. As long as you have coverage, you will be able to call again, but you are unlikely to experience smooth seamless handovers at those altitudes.

Depending on country, technology, competition and sometimes legislation, operators will or will not allow you to roam between them. So there might be a network and your phone will actually pick up its signal, but it is not allowed to attach/register itself. If that happens during a call or data session, again the call will drop. Cross country roaming is mostly not allowed and also has some legal challenges.

So, if a mobile phone is switched on and registered in a particular mobile network, it is known in which cell the phone is located. And of course, the operator will know where that cell is, geographically speaking. Depends a bit, but a cell could be several square kilometers or even larger to something only say 100 square meters.

Within most mobile networks there are technical possibilites to narrow down the location even further. Either through what is essentially triangulation or by the help of built in GPS in your (smart) phone. In some countries it is legal requirement for the mobile operator to provide precise location information with any call to emergency services (e.g. 911). So they immediately know your location.

All of the above is based on a known mobile in a known mobile network. Once you know the number you can start looking for it. If you don't know the number or you don't know the mobile network it becomes very tricky, proverbial needle in the haystack type of scenario.

The idea that you can simply trace a mobile phone that is switched on is therefor in practice a little bit more complex. Lots of articles these days on NSA capabilities. I have no idea of their capabilities other than what I can make up from the various news articles. As they tend to be written by journalists rather than Telecom and or ICT specialist I'm not so sure what they can or can't. But it seems they listen in to calls rather then actually physically locate a phone. Two very different things.

There is this persistent believe that mobile phones can be traced, even when switched off. In order for that to happen we need something akin to a Men on the moon conspiracy to make that happen. There are literally thousand of engineers involved in the specification, standardization and design of Mobile telephony systems.

What is true is that when you switch of your phone, the location where you switched off is likely to be known. You move away from that position with your phone switched off, nobody is going to be the wiser!

Jeroen

[Lalvaz]

Originally Posted by T1000

Plot looks convincing...
Which means, whoever hijacked MH370 must have coordinated the take off timings of SIA68/SQ68 either from the airport or from within SIA68 aircraft.

Scrutiny of voice call records/Text communications made by passengers of SIA68 or all calls made from singapore airport area will give refresh leads!...

Military radars would be able to detect 2 aircraft, one flying behind the other. They do not rely only on the transponder information, so MH370 would not have been able to fly in the shadow of SIA68/SQ68.

[Jeroen]

Originally Posted by Lalvaz

Military radars would be able to detect 2 aircraft, one flying behind the other. They do not rely only on the transponder information, so MH370 would not have been able to fly in the shadow of SIA68/SQ68.

Its not that straight forward. It depends on resolution and on angle. If the plane was flying straight toward ther adar the other plane behind it and a little higher it would be difficult to spot tow different planes. Their radar signature would blend in one. If the radar was positioned perpendicular to their flight path one plane flying behind the other could be spotted as a secondary radar return. All depends on the resolution. I have no idea on capabilties of military radars in that area. But ive seen suggestions these two planes would need to be flying in real close proximity, less then a few hundred feet. Commercial pilots are not taught how to that.

Jeroen

[mmxylorider]

While a lot of countries have joined the search in a localized area, would it not make sense to determine the max range with the amount of fuel on board, and ask all countries in that radius from point of origin to confirm no unidentified aircraft landed/crashed in their country.

By this one would be able to eliminate theories around terrorist targeting cities, hijacks etc. What would be left would be an unfortunate water based incident.

[manas27587]

Never knew one could fly undetected.
Have destroyed my understanding of radars.
This is really a shock if really it is as easy as this is.

Ships in the area can easily see planes flying at 5000ft and it is not ordinary for planes to fly this low.

Naval ships if didn't pay heed sounds like a security lapse.

Also if terrain cover was used , i think on radars one spots objects because of their trails.

If cover with another plane was used then too a trail would be left.

For me the plane has crashed plain and simple.

Unless it has been landed in Thailand.

Also why no possibility of the plane heading east is being considered?

There are many unhabitated land masses in Indonesia.
Flying until India is not possible unless it has been lied that the plane had 7-8 hrs of fuel.
230 passengers translate to at least 200 cellphones and if none of them can be traced only means it has crashed.
One can always argue that the plane has been landed and a jammer has been used.

Does the jammer block black box transponder signals as well?

As far as my understanding goes black box transmits signals only for 30 days , time is really running out.

[autobalan]

Ran into a simple theory about missing MH370

http://www.wired.com/autopia/2014/03...ectrical-fire/

[Jeroen]

Originally Posted by autobalan

Ran into a simple theory about missing MH370



http://www.wired.com/autopia/2014/03...ectrical-fire/

Agree, very simple

Jeroen

[one-77]

Originally Posted by autobalan

Ran into a simple theory about missing MH370

http://www.wired.com/autopia/2014/03...ectrical-fire/

Applying Occam's razor, the Langkawi theory seems the simplest explanation for the initial events.
But the later events do remain a mystery. And also why no debris have been found yet.

[sandeepmdas]

Originally Posted by autobalan

Ran into a simple theory about missing MH370

http://www.wired.com/autopia/2014/03...ectrical-fire/

Not applicable anymore as it is now clear that the aircraft started to deviate from the routine course 11 minutes before the co-pilot signed off from the KL air control. And the deviation was a programmed one.

[anujmishra]

Could this be another clue?

Residents of Maldives island saw big plane flying low over island around 6:15 AM in morning the very next day of when MH370 flight took off for Beijing.

http://www.ndtv.com/article/world/ma...ome-topstories

http://www.news.com.au/world/maldive...-1226858579129

Also, somebody in www.tomnod.com spotted the plane in a jungle in India Ocean.

Here is picture: http://files.abovetopsecret.com/file...ny53273f1a.JPG

http://www.abovetopsecret.com/forum/thread1002982/pg1

Could this be real one? Why not authorities confirming this?

[Rohit_Quad]

Here's my brothers version and findings on the missing plane. Published in The Hindu, main paper, cover page as well.

The Article in todays hindu -

http://www.thehindu.com/todays-paper...cle5803181.ece

The original article that he posted in CNN ireports

ireport.cnn.com/docs/DOC-1105961

[im_srini]

Originally Posted by anujmishra

Also, somebody in www.tomnod.com spotted the plane in a jungle in India Ocean.
Here is picture: http://files.abovetopsecret.com/file...ny53273f1a.JPG
http://www.abovetopsecret.com/forum/thread1002982/pg1
Could this be real one ? Why not authorities confirming this ?

While it's an aircraft alright, it does not look like a 777.
The 777 has a more swept back trailing edge ( of the wing ) as also the horizontal stabilizer.
The jungle aircraft in the pics looks like a much older plane.
One would also think, the engines, which stick out quite a bit from under the wings, would've been noticeable too.

[tsk1979]

Originally Posted by Jeroen

It is technically feasible or possible to be in range of a mobile network at say 35.000 feet. It is just not very likely. Mobile Network Operators want to provide radio coverage on the ground, not in the air. So typically your antenna's are pointing downwards. By the way, just because you see the antenna's mounted on the towers vertical doesn't mean they radiated evenly along a horizontal axes. We use electronic tilt. Radiowaves being radio waves and propagation will mean you get coverage in various spots, including at 35000 feet. A lot will depend on the technology and the frequency used. The higher the frequency (e.g. 1800-2300 band) the less coverage you get. 800-900Mhz will reach much further. And the old 450Mhz systems such as NMT450 had an incredible range.

When I was based in the USA and piloting my own planes, such as Cessna, Cirrus, Diamond I did some testing. I think I wrote about it on this forum as well. Cant remember the exact numbers anymore. But in general you would not get voice or data coverage above 10-12000 feet. That doesn't mean it can't happen.

Thanks for this. you are spot on.
Lemme give an example. There is a very tall building in Bangalore, infact the tallest building of bangalore.
Its on Mg road(forgot the name, locals will know) and it had a nice restaurant at the top.
Around 2003 or so, we went for dinner there. Guess what, on the top floor, there were no bars on the cell phone(Airtel).
We were far above the local tower on mg road at a steep angle.

So you are right. Towers do use electronic tilt and most of the radiation is directed lower.
It is the reason you do not get good mobile coverage in mountains even when you can see the tower down below.

[austere_sly]

Originally Posted by tsk1979

There is a very tall building in Bangalore, infact the tallest building of bangalore.
Its on Mg road(forgot the name, locals will know) and it had a nice restaurant at the top.
Around 2003 or so, we went for dinner there. Guess what, on the top floor, there were no bars on the cell phone(Airtel).

Getting cellular coverage inside buildings is sometimes different than getting it in open area. Operator usually deploy IBS (In Building Solutions) with Omni Directional antennas in buildings where they have significant customer base like Malls, Hospitals and Offices. So it is quite possible that you get better coverage inside top floor of a building than outside in an open area.