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Missing Airplane Flew On for Hours

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Re: Missing Airplane Flew On for Hours

#71
post #52

Earlier quoted context omitted.

> Do we know for a fact that it disappeared from military radar? We only know what we are told, when it comes from military sources...

This is in contrast to non-military sources, wherein we know even what we are not told?

This is in contrast to sources which make information readily known, or may be compelled by courts or the public to make information known.

Re: Missing Airplane Flew On for Hours

#72
post #53

Here is what I don't get. A plane, a HUGE plane, supposedly just disappeared. Near China. So this whole "fly under the radar" is just BS? You just need to turn off your transponder, and you can fly wherever you want?

>You just need to turn off your transponder, and you can fly wherever you want? Just from reading comments in the linked piece, it seems that is true for some parts of the world. The malay military didn't have an operational air defence radar system, or they might have had a better idea where it was going. And there are areas around the Bay of Bengal with no radar coverage either, which, if the plane was hijacked, mi…

so much for China's unstoppable military

Re: Missing Airplane Flew On for Hours

#73

Here is what I don't get. A plane, a HUGE plane, supposedly just disappeared. Near China. So this whole "fly under the radar" is just BS? You just need to turn off your transponder, and you can fly wherever you want?

The range at which Radars can detect planes is a lot shorter than most people seem to believe. Ground based Radars have an effective range of something in the region of 200miles due to the earth's curvature. To get around that you either have to have air based Radars (such as the E2-Hawkeye used by US carrier groups), or more exotic/experimental types of radars which bounce off the ionosphere.

The limitations of radar are part of the reason why Aircraft have transponders - you can pick up an actively broadcasting radio from far greater range, and you're not relying on getting a clean bounce back from the aircraft. They're also the reason why carriers carry multiple E2s - a radar on the top of a mast on a ship simply can't see far enough.

Re: Missing Airplane Flew On for Hours

#74

So we have a plane that flew to another destination without communication and several people with bogus passports on board. Familymembers have reported cellphones that kept 'rining' instead of going directly to voicemail (as they would have if the plane was at rhe bottom of the ocean). Hijacking looks to me the only reasonable explenation.

So after 5 days, the hijackers are allowing all the hostages to charge their phones?

Re: Missing Airplane Flew On for Hours

#75
post #53

Earlier quoted context omitted.

>You just need to turn off your transponder, and you can fly wherever you want? Just from reading comments in the linked piece, it seems that is true for some parts of the world. The malay military didn't have an operational air defence radar system, or they might have had a better idea where it was going. And there are areas around the Bay of Bengal with no radar coverage either, which, if the plane was hijacked, mi…

so much for China's unstoppable military

Malaysia is not China? For most of the plane's expected flight it was outside Chinese airspace.

Re: Missing Airplane Flew On for Hours

#76
post #67
post #31

Earlier quoted context omitted.

Minutes, not seconds.

Sorry about that. Fixed. Wouldn't my question still hold? It's talking to a ground network.

Why ground? I'd do that as an L-band ORBCOMM type system, since it's going on planes operating over oceans. $0.01/character.

Re: Missing Airplane Flew On for Hours

#77

So we have a plane that flew to another destination without communication and several people with bogus passports on board. Familymembers have reported cellphones that kept 'rining' instead of going directly to voicemail (as they would have if the plane was at rhe bottom of the ocean). Hijacking looks to me the only reasonable explenation.

It's possible in some cases for phones to "ring" even if they're off/disconnected, as the tone is generated by the network, not the device itself.

Is there is some sort of timeout after which it gives up, or a reliable upper bound on the time it takes for a network search, and if so, do you know how long either of those two periods are?

I presume that if you ring a phone, a search is initiated, which would result either the phone being located or the phone being marked as unavailable, and that once the latter had happened you wouldn't get the ringing tone until the phone re-registered on the network.

I only ask because, from memory, the reports that I saw seemed to suggest that people got ringing tones for quite a while, and a cursory search just now indicates phones are still ringing days after the disappearance.

If that was so (unverified assumption), wouldn't that suggest that the network search hadn't yet failed to locate those phones, and that after some period of time that amounts to pretty good evidence that the phones were still connected?

Re: Missing Airplane Flew On for Hours

#80
post #62

They claim some of the cell phones are still active. Can't they just "traceroute" the call to find the nearest cell tower and search around it?

I don't think they can, because the phones aren't connecting. Apparently what is actually happening is that the exchange is connecting and people are confusing that with the phone.
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