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Missing Airplane Flew On for Hours

online.wsj.com

121–130 of 215 posts

Re: Missing Airplane Flew On for Hours

#121

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?

This was on HN a couple days ago: http://en.wikipedia.org/wiki/2003_Boeing_727-223_disappearan...

Just 10 years ago someone has stolen a Boeing 727 from an airport,took off, turned off the transponder and landed somewhere. Even FBI looked for that plane and couldn't find it. So I guess it's very much possible to fly undetected.

Re: Missing Airplane Flew On for Hours

#122
post #31

Earlier quoted context omitted.

Minutes, not seconds.

Wait a minute. WTF? If the system sends signals EXACTLY every 30 minutes, then a very careful reconstruction of signal running times (combined of course with the positions of the recieving antennae and the EXACT times the signals were recieved) can reveal information about the heading and position.

That's a good point, if the timestamps have the necessary precision and their clock drift info hasn't been lost by a resync since then. I'd guess that since exact time isn't crucial to the purpose of these messages, though, that they probably don't have very high precision timestamps. :-(

Re: Missing Airplane Flew On for Hours

#123

Earlier quoted context omitted.

I mean, it would seem easier to steal the cargo at the airport before it got on the plane, just bribe a few ground workers, I guess. Steal some passports, hijack, then divert the plane just for cargo? It wasn't the cargo; the only reason to hijack the plane would be either the people or the plane or both. Or, it was an accident.

http://en.wikipedia.org/wiki/Brussels_Airport_diamond_heist

Seems like a lot of work. I would prefer just hacking a bitcoin exchange.

Re: Missing Airplane Flew On for Hours

#124
The Malaysian transport minister has just denied this article's accuracy at a press conference in KL.

Which is interesting. The WSJ isn't just some random blog. I wonder where they got their information.

Re: Missing Airplane Flew On for Hours

#125
post #68

Why no one is paying attention to the fact that the plane was flying over South China see which China is trying to claim for itself. Could it be the case that China by mistake shot the plane down ?

More than half the passengers were Chinese. That wouldn't go down very well with the home crowd.

Re: Missing Airplane Flew On for Hours

#126

This begs the question: why on earth is it even possible to turn off a transponder mid-flight on a commercial plane carrying hundreds of human beings? I also don't understand why, if we can send bursts of engine data every 30 minutes from the middle of the ocean, we can't send a GPS location every couple of minutes. Maybe even throw some GPS data in with the engine data - at least we would know where it was within a…

If it malfunctions you don't want it to overheat and burn the plane down. Thus the ability to cut power.

Re: Missing Airplane Flew On for Hours

#127
post #124

The Malaysian transport minister has just denied this article's accuracy at a press conference in KL. Which is interesting. The WSJ isn't just some random blog. I wonder where they got their information.

They also put three journalists in the by-line. Is that typical?

Re: Missing Airplane Flew On for Hours

#128
post #97
post #41

Earlier quoted context omitted.

Instead of turning your phone off, so that it can inform the network that it is going off line, try pulling the battery without warning. If I turn off my phone gracefully, the network will send incoming calls pretty much straight to voicemail. If my phones battery has died, or the phone dropped off the network for another reason (went camping?), then the network will have your phone ring as it searches for the phone.

No, you will not hear a ringing. The ringing only starts after the phone you are calling has been contacted. When you pull the battery out, the network will keep on searching for your phone and since no phone replies, it will inform you that the phone is out of coverage area.

In my experience cellular phone networks behave very differently in different countries.

In some places I have made calls where I first hear one kind of ring which is then replaced by a second, different kind of ring. A hypothesis is that one network has played a ring tone while it connects to another network, and that the second network plays the other ring tone as the actual phone is ringing. I have even heard three different kinds of tones when making calls to phones that are roaming in foreign countries.

The global phone network is an incredibly heterogeneous spaghetti of different networks built with different gear installed at different times. The internet looks positively homogenous by comparison.

My point is that you shouldn't rush to positively say "No, you will not hear a ringing."

Re: Missing Airplane Flew On for Hours

#129
post #93

Biggest mystery.

Indeed. It looks like everything either malfunctioned or was intentionally turned off all at once. A long time ago one of my servers had a very crude monitoring system, it would send me an email every half hour saying "I'm still alive!". Hard to believe that kind of simple thing can't be implemented on a 21st century airliner ( or maybe it is, then forgive my ignorance please). A simple beep beep signal saying "I'm still flying!", every minute or so, with the plane's location as a bonus.

Edit: that said, if the plane starts breaking apart at cruising altitude, it wouldn't help much with finding it...so maybe self-powered transponders in nose, tail, wings, engines etc etc, nicely sealed in "black box" style casings might help. Or maybe they have that already and I know absolutely nothing about modern planes (or planes in general).

Re: Missing Airplane Flew On for Hours

#130
post #89

Earlier quoted context omitted.

So why don't planes do that that? You need 24 bits for 3 meter GPS accuracy (times 2). Add some extra for altitude and airplane ID (or does a unique ID come built in?) So maybe 80 bits in total. This would be nothing for an airplane - $0.40 per hour? Why don't they do this already?

>This would be nothing for an airplane - $0.40 per hour? Why don't they do this already? They would likely receive pushback from private jets that don't want all of their flight path transmitted back to RR.

I don't know what RR is, but you don't have to transmit to any central authority. Just to the plane owner.

Make a law that the owner has to preserve the data for one week, but doesn't have to provide it to anyone.

And doesn't the US military track every overland flight anyway?

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