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nupogodi
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 4:50 pm

Quoting Lizzie (Reply 199):
Thanks - could you explain "CFR/FDR ULB"?

Cockpit Voice Recorder

(Digital) Flight Data Recorder [some people like to be pedantic and call it DFDR]

Underwater Locator Beacon

edit: I know Cockpit Voice Recorder doesn't make sense for CFR, but Kaihari (sp?) made a typo, it's called the CVR.

[Edited 2014-04-07 09:52:10]
A man must know how to look before he can hope to see.
 
MD11Engineer
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 4:50 pm

I have tested these Dukane ULBs after doing routine changes of their batteries. It is actually quite easy. One needs a piece of wire to bridge the terminal in the middle to the rest of the housing (when submerged, this connection will be made by the water) and listens to the sound it makes (in air) using a frequency converter (similar units are being used e.g. by zoologists to listen to the ultrasonic calls made by bats).

Let's say one beacon would produce a sound like krk-krk-krk-krk, with a krk about every second.
If you had two beacons, they would not be synchronised, but would sound like krk,krk-krk,krk-krk,krk etc.

It is the same when you do an audible test of a jet engine's ignitor plugs (there are usually two of them, with indepedent ignition systems):
One plug firing would be: clack-clack-clack-clack etc.
Both plugs firing would be: clackclack-clackclack-clackclack etc.

Jan
Je Suis Charlie et je suis Ahmet aussi
 
rfields5421
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 4:51 pm

Quoting LTC8K6 (Reply 173):
I don't think there is any way that the signals which are 600kms apart are the same signal.
Quoting Finn350 (Reply 174):
I don't think that the Chinese could have detected the same source 300 nm away. The range of a pinger is a few kilometers.

There are many cases of nuclear powered submarines running in quiet mode being detected by sound over 6,000 km away. These sounds were not detected at stations 2,000 km and 3,800 km away.

Ocean currents can provide conduits enabling sound to travel far, far beyond what anyone would expect and make someone far away from the sound source better able to detect the sound than someone closer.

Each area of the ocean is different and changes of conditions affect the transmission of sound significantly.

I personally have great doubt about the Chinese report, however, I do not discount it as impossible. Highly unlikely, yes, but not impossible.
Not all who wander are lost.
 
lipzoan
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 4:53 pm

CVR cockpit voice recorder
FDR flight data recorder
ULB underwater locator beacon
 
MD11Engineer
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 4:55 pm

Quoting rfields5421 (Reply 202):
There are many cases of nuclear powered submarines running in quiet mode being detected by sound over 6,000 km away. These sounds were not detected at stations 2,000 km and 3,800 km away.

Ocean currents can provide conduits enabling sound to travel far, far beyond what anyone would expect and make someone far away from the sound source better able to detect the sound than someone closer.

Yup. Compare underwater sound conduction to HF propogation in the atmosphere.

Jan
Je Suis Charlie et je suis Ahmet aussi
 
Lizzie
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 4:59 pm

Quoting nupogodi (Reply 200):

Thanks! I figured they probably meant that, but it's good to know. In that case I will revise my Bayesian priors upwards  

I know that finding the plane would be the end of hope for families, and so not exactly "good" news, but at this stage, hope seems more cruel than kind.

I hope the plane is found.
 
SimonDanger
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 5:04 pm

Heard on the radio just now:

ABU DHABI, United Arab Emirates —
The director of the International Air Transport Association said Monday he wants to see a globally agreed upon tracking standard in place by the end of this year, which also takes into consideration the cost on airlines, in order to avoid another disappearance like that of Malaysia Airlines Flight 370.


I tried to search the way-back machine and couldn't find my earlier reference but I suggested that significant events such as this missing airliner have a way of causing large changes in the way we normally do things. It was probably evident that this event would cause us to update our monitoring of airliner locations, but even I am surprised to see this so quickly.

http://seattletimes.com/html/busines...ysiaplaneiata.html?syndication=rss
 
Unflug
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 5:05 pm

Quoting rfields5421 (Reply 202):
There are many cases of nuclear powered submarines running in quiet mode being detected by sound over 6,000 km away. These sounds were not detected at stations 2,000 km and 3,800 km away.

Ocean currents can provide conduits enabling sound to travel far, far beyond what anyone would expect and make someone far away from the sound source better able to detect the sound than someone closer.

Correct, and hence:

Quoting rfields5421 (Reply 202):
I personally have great doubt about the Chinese report, however, I do not discount it as impossible. Highly unlikely, yes, but not impossible.

100% agree.
 
nupogodi
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 5:09 pm

I don't think comparing the low-frequency noise generated by a nuclear-powered submarine to the high-frequency noise produced by a battery-powered beacon the size of your forearm is really doing much to further the idea that its signal propagating 600km is remotely possible.
A man must know how to look before he can hope to see.
 
flyenthu
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 5:24 pm

Can someone explain this to me, I am confused. How was this new search area identified?

How was this new search area established- the latest one where Ocean Shield has been dispatched? Did the Chinese ping detection initiate it? My understanding was that the search area before Haixun 01 detected the pings was hundreds of miles away and in a different area. Yet, the media is saying that the Chinese ping detection is unreliable and that the Chinese equipment used was not advanced.

Thank you.
 
MD11Engineer
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 5:29 pm

Quoting flyenthu (Reply 209):
My understanding was that the search area before Haixun 01 detected the pings was hundreds of miles away and in a different area. Yet, the media is saying that the Chinese ping detection is unreliable and that the Chinese equipment used was not advanced.

Are you sure that the equipment shown in the video was the one they actually used to detect the signal?
It is quite possible that they have some advanced military hardware, they don't want the others to know about.

Jan
Je Suis Charlie et je suis Ahmet aussi
 
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Finn350
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 5:30 pm

Quoting MD11Engineer (Reply 204):
Yup. Compare underwater sound conduction to HF propogation in the atmosphere.

I found this calculator of absorption of sound in seawater:
http://resource.npl.co.uk/acoustics/techguides/seaabsorption/

Using frequency of 37.5 kHz and water depth of 4 km, it gives attenuation of around 6 dB/km. That means that a 165 dB out will be attenuated to zero in less than 30 km. When considering background noise, the actual detectable range would be less.

Now I would like to see some scientific explanation why this attenuation calculation is wrong and we can instead compare sound wave propagation in water to electromagnetic waves propagating in air or the near vacuum of the upper atmosphere, which is completely different physical phenomenon.
 
flyenthu
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 5:34 pm

Quoting MD11Engineer (Reply 210):
Are you sure that the equipment shown in the video was the one they actually used to detect the signal?

You mean the Chinese equipment? I am not sure what equipment was used. CNN mentioned hydrophone, which to me is quite basic. But, I see your point. The reason I am asking is that shifting assets to the new search area is probably based on stronger data than what they are letting on. Otherwise, it is again the proverbial wild goose chase.
 
nupogodi
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 5:34 pm

Quoting Finn350 (Reply 211):
Using frequency of 37.5 kHz and water depth of 4 km, it gives attenuation of around 6 dB/km. That means that a 165 dB out will be attenuated to zero in less than 30 km.

Considering the ULB would be at 157dB by now, it would be even worse. Each ~3dB is halving the power, so it would very quickly be reduced to background noise even if it was technically detectable.
A man must know how to look before he can hope to see.
 
Backseater
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 5:36 pm

Quoting rfields5421 (Reply 202):
Ocean currents can provide conduits enabling sound to travel far, far beyond what anyone would expect and make someone far away from the sound source better able to detect the sound than someone closer.

Yes and maybe if the pinger is not on a flat bottom, the sound might be reflected in one specific direction, provided the reflecting obstacle if of an appropriate material and texture

Note: years ago I remember receiving San Diego TV well and consistently with a rotating antenna from North of LA, not by pointing the antenna south towards San Diego in which case I got mostly noise, but due north towards the mountain I was on the foothills of.
 
AviRaider
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 5:42 pm

If this lead does turn out to be the aircraft, does that mean that this will be the first case where a crash site was located not by debris?
 
canoecarrier
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 5:44 pm

Quoting MD11Engineer (Reply 210):
Are you sure that the equipment shown in the video was the one they actually used to detect the signal?
It is quite possible that they have some advanced military hardware, they don't want the others to know about.

I've thought for a while now that China and the US may be using some military capabilities they're not publicly letting on about. Although I doubt this is what they're using, we didn't know for decades that the US had a chain of underwater listening posts around the world, which is how they found the USS Thresher and K-129 wreck sites.

It's entirely possible they have classified satellite or acoustic capabilities that helped them narrow down the area to search.
The beatings will continue until morale improves
 
Lizzie
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 5:44 pm

Quoting Finn350 (Reply 211):
Now I would like to see some scientific explanation why this attenuation calculation is wrong and we can instead compare sound wave propagation in water to electromagnetic waves propagating in air or the near vacuum of the upper atmosphere, which is completely different physical phenomenon.

The calculation isn't wrong, but the caveat you need is given in your source:

Note that the absorption causes only part of the transmission loss. Usually, the major contribution to transmission loss is the spreading of the acoustic wave as it propagates away from the source.


It's the basis of the science of room acoustics. In the open air, a shout will not carry. In a tunnel, it will.

In fact, it's the same principle as the principle that means that fibre optics can bend light round corners! Or round the Whispering Gallery in St Paul's Cathedral.

The ocean bottom is a potential reflecting surface, and density discontinuities in the ocean above are potential reflecting surfaces too. So given the right conditions the sound wave can travel as though under a concrete ceiling, rather than as under an open sky.
 
11Bravo
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 5:46 pm

Quoting nupogodi (Reply 195):
There are a crapload of submarine cables coming from Perth...

It seems as though there are four cables rather than an actual crapload.   That "map" looks more like a wiring schematic rather than a proper map with surveyed locations. I don't think you could plot locations with any accuracy on that map.
WhaleJets Rule!
 
nupogodi
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 5:49 pm

Quoting 11Bravo (Reply 219):
It seems as though there are four cables rather than an actual crapload.   That "map" looks more like a wiring schematic rather than a proper map with surveyed locations. I don't think you could plot locations with any accuracy on that map.

I agree. Also, the "four cables" represented on the map are certainly not the count of physical cables. They may be individual cable installations, but that isn't to say that one "cable" on the map doesn't represent multiple physical links.

Actually the whole business of submarine cables is incredibly fascinating, a lot of non-technical people don't even realize that they exist.
A man must know how to look before he can hope to see.
 
nupogodi
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 5:54 pm

Quoting Lizzie (Reply 218):
It's the basis of the science of room acoustics. In the open air, a shout will not carry. In a tunnel, it will.

Actually what you quoted only strengthens what he said. It says that the spreading of the wave decreases its power, not necessarily absorption from the medium.

When you are talking about a tunnel, or maybe an opera hall, the acoustics are designed not to absorb the sound, but to *direct* it. If we start comparing sound waves to EM waves again, this is how fibre-optic cables work, they reflect the light inward to the fibre to minimize losses yet they still occur. Anyhow... it's still impossible! Even if the ocean was in perfect condition! The absorption from the water will degrade the signal, but most of all over distance, the spreading of the signal will degrade it. Past a certain point you might hear it but you won't be able to tell it from background noise.
A man must know how to look before he can hope to see.
 
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Finn350
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 5:57 pm

Quoting Lizzie (Reply 218):
Note that the absorption causes only part of the transmission loss. Usually, the major contribution to transmission loss is the spreading of the acoustic wave as it propagates away from the source.

It's the basis of the science of room acoustics. In the open air, a shout will not carry. In a tunnel, it will.

That only reinforces my case, as I calculated only the absorption rate. In other words, the absorption calculation is under the most optimal conditions, i.e. the sound wave wouldn't spread at all from the source (pinger) to the detector.

Edit: Nupogodi made exactly the same point first.


[Edited 2014-04-07 10:59:50]
 
Lizzie
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 6:12 pm

Quoting Finn350 (Reply 222):
That only reinforces my case

Well, no, it doesn't. As your source says, absorption is only a small part of the loss. Spreading of the wave is the major contribution.

So if you constrain the spreading of the wave (as between two reflecting surfaces) you vastly reduce the loss.

As you can readily verify by comparing the transmission of a shout in an open field to a shout in a multi-storey car park!

[Edited 2014-04-07 11:13:06]
 
nupogodi
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 6:18 pm

Quoting Lizzie (Reply 223):
Well, no, it doesn't. As your source says, absorption is only a small part of the loss. Spreading of the wave is the major contribution.

Even assuming total internal reflection (good luck finding that in nature), absorption will dominate and kill the signal quite quickly anyway.

Look, I don't care if you believe me. An ULB being heard 600km away is physically impossible. That's just all there is to it.
A man must know how to look before he can hope to see.
 
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Finn350
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 6:18 pm

Quoting Lizzie (Reply 223):
Well, no, it doesn't. As your source says, absorption is only a small part of the loss. Spreading of the wave is the major contribution.

I calculated the loss due to the absorption, which is around 6 dB/km. As you say, that is only a small part of the loss. The effective range of the beacon is just a few kilometers, not 30 km based on the absorption loss alone and no background noise.

[Edited 2014-04-07 11:19:01]
 
Lizzie
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 6:22 pm

Quoting nupogodi (Reply 224):
Even assuming total internal reflection (good luck finding that in nature), absorption will dominate and kill the signal quite quickly anyway.

I'm not claiming that "total internal reflection" is found in nature. I am claiming that transmission loss by spreading is much greater than by absorption, as Finn's source says.

Quote:

Look, I don't care if you believe me. An ULB being heard 600km away is physically impossible. That's just all there is to it.
OK!



http://www.telegraph.co.uk/news/worl...point-as-final-half-handshake.html


[Edited 2014-04-08 07:43:19 by SA7700]
 
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bikerthai
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 6:30 pm

Quoting BackSeater (Reply 214):

Yes and maybe if the pinger is not on a flat bottom, the sound might be reflected in one specific direction, provided the reflecting obstacle if of an appropriate material and texture

Then can anyone comment on the following possibility?

Considering that with a regular voice, once can amplify the magnitude of the sound wave by placing a funnel over your mouth.

Is there any possibility that the fuselage of the aircraft can distort the signal so that it may have an amplified signal in one direction and reduced in another?

From my understanding these FDR & CDR's are typically located on top of the ceiling panel on Boeing aircraft.
The ceiling panels are graphite phenolic and not much of an electrical amplifier. However if the aft fuselage break off from the wing box, how would this configuration affect the ping signal?

bt
Intelligent seeks knowledge. Enlightened seeks wisdom.
 
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Finn350
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 6:33 pm

Quoting bikerthai (Reply 228):
Considering that with a regular voice, once can amplify the magnitude of the sound wave by placing a funnel over your mouth

To amplify something, you need external power. A funnel (or any other structure) can just direct the sound, i.e. make it spread less.
 
nupogodi
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 6:33 pm

Quoting Lizzie (Reply 227):
I'm not claiming that "total internal reflection" is found in nature. I am claiming that transmission loss by spreading is much greater than by absorption, as Finn's source says.

You don't need the scare-quotes, Lizzie, it's a real thing.

If you think that spreading dominates, the range is impossible. If you think that absorption dominates due to a freak natural phenomenon, the range is impossible.

Either way...
A man must know how to look before he can hope to see.
 
Lizzie
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 7:00 pm

Quoting nupogodi (Reply 230):

You don't need the scare-quotes, Lizzie, it's a real thing.

They weren't "scare-quotes", nupogodi (and those aren't either) - they were actual quotes! I was quoting you!

Yes, I know. And I am very well aware that total internal reflection, with or without scare quotes, is not found in nature - there is always some loss.

But reflection sure as heck improves transmission, as the Whispering Gallery demonstrates.

Yes, you get loss of amplitude through absorption over distance, but if you are also getting reinforcement from reflection you will hugely increase the power of the signal per unit distance.

As is easily demonstrated! There's a reason buskers like to play in subway tunnels!
 
Lizzie
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 7:03 pm

Quoting Finn350 (Reply 229):

To amplify something, you need external power. A funnel (or any other structure) can just direct the sound, i.e. make it spread less.

Absolutely right. And, if you make it spread less - specifically, if your reflected signal reinforces the direct signal, as well as other reflected signals, you will get greater power at greater distance, albeit over a much reduced pick-up area. But if your ear, or your microphone, is in that area, you will hear hugely better than if there was no reflection.
 
nupogodi
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 7:08 pm

Quoting Lizzie (Reply 231):
There's a reason buskers like to play in subway tunnels!

Because they can get permits there and not get chased away by cops and there is guaranteed foot traffic and it's indoors?

edit: Also I'm pretty sure they're in the stations, not in the tunnels. There are trains in the tunnels!

[Edited 2014-04-07 12:12:38]
A man must know how to look before he can hope to see.
 
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ssteve
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 7:11 pm

Quoting Lizzie (Reply 226):

Missing plane black-box pings tracked to same point as final half-handshake

So is it plausible the satcom system was restarting after the RAT deployed?

I also have to say the terminology is regrettable here. The satcom network pings are different from pinger pings which are different from that some people were calling pings on radar.  Big grin

[Edited 2014-04-07 12:13:10]
 
Lizzie
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 7:13 pm

Quoting nupogodi (Reply 233):
Because they can get permits there and not get chased away by cops and there is guaranteed foot traffic?

I agree that that is a contributory factor! But you should walk from South Ken tube station to the Natural History Museum some time. As near to total internal reflection as you'll get  It also helps that the Royal College of Music is nearby.

ETA:


edit: Also I'm pretty sure they're in the stations, not in the tunnels. There are trains in the tunnels!


In the UK, "subway" usually means a walking tunnel, under a road or between stations. Great places for busking!

[Edited 2014-04-07 13:10:14]
 
nupogodi
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 7:13 pm

Quoting SSTeve (Reply 234):
So is it plausible the satcom system was restarting after the RAT deployed?

That was my theory and everyone else's theory. Took a swim before it connected to the network.
A man must know how to look before he can hope to see.
 
nupogodi
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 7:14 pm

Quoting Lizzie (Reply 235):
But you should walk from South Ken tube station to the Natural History Museum some time. As near to total internal reflection as you'll get 

I've been there, actually. Didn't notice that, though I wasn't paying that much attention.
A man must know how to look before he can hope to see.
 
Lizzie
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 7:15 pm

Quoting SSTeve (Reply 234):
The satcom network pings are different from pinger pings which are different from that some people were calling pings on radar. Big grin

And doppler ping data is different from hand-shake ping data! And the frequency of the pings is different from the ping frequency! Definitely too many damn pings 
 
terlanmat68
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 7:26 pm

I don't know if this has been shared or not, but I found chapter 2 of some interest for my understanding.

http://www.supsalv.org/pdf/VOL%204.pdf

[Edited 2014-04-07 12:28:37]
 
BA84
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 8:20 pm

Quoting nupogodi (Reply 233):
Quoting Lizzie (Reply 231):
There's a reason buskers like to play in subway tunnels!

Quoting nupogodi (Reply 233):
Also I'm pretty sure they're in the stations, not in the tunnels. There are trains in the tunnels!

Let me translate:

In UK, subway means pedestrian tunnel.

In Great Toronto, subway means Underground railway.

BA84
 
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sassiciai
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 8:52 pm

In my opinion, here in Thread 51 it is all too evident (and that since many threads before) that in the absence of any real news, these threads are in a quality spiral dive, driving many normally active a.netters off this thread!

I check in every day (or recently, every second/third day), and diagonally scan the new posts, looking for some real news and/or insightfull comment. I no longer find that, and it's sad to say that some current "discussions" here are quite shallow.

I do wish that all posters in this particularly difficult thread would try the acid test of whether their post adds to the thread content, and would be seen as constructive to any family members of the pax & crew who happened to read it

As this post adds nothing to the topic, I guess it will be deleted soon by the moderators, but I for one ask for some help from them to keep this thread at an appropriate level!
 
nupogodi
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 8:53 pm

Quoting sassiciai (Reply 244):
I do wish that all posters in this particularly difficult thread would try the acid test of whether their post adds to the thread content

Alright. I have taken some acid. What do I do now?

edit: But seriously relax. mandala's still around, Pihero's still around, everyone else whose names I forget are still around. There's going to be BS naturally when there is no news, but some productive stuff has come of it, so don't be so judgemental. A big thread doesn't cost anything but a few kilobytes in bandwidth, let people talk as they wish. As long as they don't break the rules, what's the harm? All we can do is spin our wheels until the SAR effort can confirm something, and that may be a while.

[Edited 2014-04-07 13:58:02]
A man must know how to look before he can hope to see.
 
BA84
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 9:26 pm

Quoting sassiciai (Reply 244):
In my opinion, here in Thread 51 it is all too evident (and that since many threads before) that in the absence of any real news, these threads are in a quality spiral dive, driving many normally active a.netters off this thread!

I check in every day (or recently, every second/third day), and diagonally scan the new posts, looking for some real news and/or insightfull comment. I no longer find that, and it's sad to say that some current "discussions" here are quite shallow.

I suggest you re-read all Warren Platts' posts,
while you're waiting for someone to say something intelligent.
Shallow discussions are available on CNN, 24/7.

BA84
 
sipadan
Posts: 322
Joined: Wed Mar 12, 2014 7:06 am

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 9:26 pm

Commander Marks of US naval 7th fleet : " We are less optimistic now then we were 12 hours ago. Over the last 12 hours we have been unable to re-aquire the signal with the pinger locater. Our optimism is diminished but we are still hopeful."
 
holzmann
Posts: 599
Joined: Mon Jan 17, 2011 3:43 pm

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 9:30 pm

Would be such a shame if the batteries died within hours of being found.

What about bringing out some sort of metal detector?

How were the AF447 boxes found after so many years?
DISCLAIMER: Airliners.net is an AIRBUS forum. Boeing Commercial Airplanes, if it has considered doing so in the past, should in no way consider supporting this website.
 
nupogodi
Posts: 933
Joined: Mon Mar 10, 2014 10:58 am

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 9:35 pm

Quoting holzmann (Reply 248):
How were the AF447 boxes found after so many years?

Remotely operated submersible with side-scanning sonar I believe.
A man must know how to look before he can hope to see.
 
Trin
Posts: 167
Joined: Mon May 02, 2011 4:45 pm

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 9:54 pm

Quoting SimonDanger (Reply 206):
I tried to search the way-back machine and couldn't find my earlier reference but I suggested that significant events such as this missing airliner have a way of causing large changes in the way we normally do things. It was probably evident that this event would cause us to update our monitoring of airliner locations, but even I am surprised to see this so quickly.

I'm not surprised in the slightest - quite frankly. I think coming out and saying this the very next day after MH370 got "lost" would have been TOO LATE. In this day and age, it is absolutely unconscionable that an airliner with 200+ souls on board can go 'missing' for a month or more, and the world has NOTHING to show for it.

We have GPS, we have satellites, we have satellite broadband internet capability. The fact that the airline industry still relies on transponders and radars and radio is just mind-boggling.
 
nupogodi
Posts: 933
Joined: Mon Mar 10, 2014 10:58 am

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 10:00 pm

Quoting Trin (Reply 247):
We have GPS, we have satellites, we have satellite broadband internet capability. The fact that the airline industry still relies on transponders and radars and radio is just mind-boggling.

We have GPS and we have satellites but relying on radio is mindboggling? How exactly do you think GPS and satellites work?

The transponder is a fantastic piece of technology. Radar is ridiculously sophisticated.

I would agree with you that the audio comms suck... it's really stupid that you can stomp on someone's transmission... but it works well enough and hasn't caused any safety problems.
A man must know how to look before he can hope to see.
 
Kaiarahi
Posts: 1810
Joined: Tue Jul 07, 2009 6:55 pm

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 10:10 pm

Quoting Trin (Reply 247):
We have GPS, we have satellites, we have satellite broadband internet capability. The fact that the airline industry still relies on transponders and radars and radio is just mind-boggling.

GPS and satellites won't tell you anything about altitude, which is kind of important in managing air traffic. Voice communications divided up by multiple frequencies (i.e. radio) are sort of useful as well.
Empty vessels make the most noise.
 
nupogodi
Posts: 933
Joined: Mon Mar 10, 2014 10:58 am

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 10:25 pm

Quoting Kaiarahi (Reply 249):
GPS and satellites won't tell you anything about altitude

GPS will ... but the receiver has to downlink that data somewhere.
A man must know how to look before he can hope to see.
 
747megatop
Posts: 1785
Joined: Wed May 23, 2007 8:22 am

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 51

Mon Apr 07, 2014 10:44 pm

Quoting Trin (Reply 247):
The fact that the airline industry still relies on transponders and radars and radio is just mind-boggling.

Reliance on transponders, radars and radio is not mind boggling. What is mind boggling is that the 777 developed stealth capabilities  .
We were quite lucky that the aircraft was pinging the INMARSAT satellite at regular intervals, otherwise 40 +ships and 25+ aircraft would have looked in South China sea and the Gulf of Thailand for over a month without the finding the aircraft thereby declaring it "vanished without a trace"! Who would have known that the aircraft flew for 5+ hours after loss of contact? Even more mindbloggling is that the militaries in that region did not pick up a UFO in their airspace in the post 9/11 world   . This incident has definitely exposed vulnerabilities that need fixing.

It will be interesting to see what solutions the industry comes up with so that aircrafts will remain traceable/trackable at all times without the option of accidentally or intentionally disabling that capability.
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