Air France jet vanishes from radar

[X-man]

Ok, but such thunderstorm will be visible outta space, what's left for a plane flying straight to it? Such a powerful CB can smash anything daring to fly through it's core. And it's not the lightnings but rather the turbulence and hail that could cause structural damage. All pilots worldwide train to recognize and avoid such atmospheric phenomenas, if they've had a 50k feet CB wall in front of them they should have tried to go back.

 

At these latitudes, CBs can form very, very quickly and it's not alway possible to predict this before the flight. And once the flight is airborne, they're not getting real time weather updates from satellites. Also remember, the area in question was OUTSIDE any ATC coverage, so no intel from them. Their primary source of info would have been their WX-radar (IIRC Thunderstroms in the Convergence zone can sometimes be hard to detect coz they are drier than normal). This together with the fact that it was night -> tricky to spot CBs. It's not always possible to go around or divert, so sometimes you have to navigate through the "calmer" parts of the storm using your WX-radar.

 

Maybe Lightning (or something else) took out the WX-radar and the crew was unable to navigate safely through the storms and ended up in particularly bad turbulence which might have caused the catastrophic event.

 

Check this out, very interesting analysis: http://www.weathergraphics.com/tim/af447/

[sniffer]

Check this out, very interesting analysis: http://www.weathergraphics.com/tim/af447/

 

Good find!

 

Grab another analysis @ Aviation Herald

[rogue_blade]

well debris from the crash has been confirmed including a seat, life jacket, bits of metal and jet fuel, other bits and even a turbine or some engine part.

 

Thing is....earlier today they say at first the automated messages sent from the aircraft reported electrical system failures and compression issues.

Now they say the computer reported "complete system failure" and decompression. So that in combination with the lack of any form of mayday call means it must have been a near instant, if not instant catastrophic event. I mean unless all forms of comms were knocked out and things progressed from bad to worse thereafter and the pilots simply had no way of communicating....but I'm thinking the former is what occurred....

 

I am quite baffled as to how it can be so hard to find a downed aircraft. I would assume airlines would have live data feeds of gps co-ordinates their entire flights. And if so, surely they could calculate how far the aircraft could have traveled based of the last gps coordinate received? I honestly have no idea how this stuff works, just thinking out loud here. And apart from GPS what about some other form of satellite tracking, I mean isnt there some sort of satellite to aircraft datalink going on or something, like anything!?

And then this blackbox. We always have to retrieve them and their valuable data which is always a huge task. Why don't these black boxes send a live data stream constantly throughout a flight? Like the same way they recieved the automated messges of the electical and pressuriztion failures?

I don't know, I'm just confused and annoyed as to how it is so difficult to find a crashed jet.

Edited June 3, 2009 by rogue_blade

[joey45]

if the A/C decompessed then it would of broken up mid air... and at 30 odd thousond feet...

[jpm1]

if the A/C decompessed then it would of broken up mid air... and at 30 odd thousond feet...

 

the lack of SOS suggests a brutal event . it's strange because belonging to experts there are very few chances for lightnings to cause such plane to crash seems the worst lightnings could do is to grill some electrical sytems but on modern planes all electrical systems are doubled or tripled , but the "electrical system failure" is a symptom of a lightning strike or they didn't had luck at all

[Pilotasso]

Tank ignition or bomb. I cant see what else unfortunatly. in the case of tank ignition the explosion could have been picked up by NORAD as a big thermal blob. the tanks were probably mostly full. Thats a big IR signature to see.

[Force_Feedback]

It still surprises me that civillian aircraft don't have: round DFDR/CVRs, they can withstand so much more force for a given weight (the Russkies have such shape), and why the FRD/CVRs don't float up when contacting water in a crash. Even the damn Su-33 has such black box, a military jet where every kg is punished by death (in Russia :P).

 

Oh, yeah, I forgot, $$$$$$ it's not funny, in a rich man's world...

[ARM505]

Even if the DFDR and CVR could float, the tons of metal aeroplane and structures to which they are mounted generally don't.... And who says the boxes needed to be stronger? Chances are, they have survived the event, and just need to be found - That's the hard part, despite their underwater location equipment. Given the origin of the aircraft (Airbus), and the carrier (AF), I've no doubt that the money will be spent to locate and investigate.

[-fox-]

And who says the boxes needed to be stronger? Chances are, they have survived the event, and just need to be found - That's the hard part, despite their underwater location equipment. Given the origin of the aircraft (Airbus), and the carrier (AF), I've no doubt that the money will be spent to locate and investigate.

 

What puzzles me is that the black boxes transmit their signals for 30 days only. Shouldn't it be possible to extend that with modern accumulators? It sure is a strong sonar signal, that consumes plenty of energy but still...

 

Edit: Here's an interesting article about how they work, btw..

Edited June 3, 2009 by -=fox=-

[sniffer]

Today media talks about informing/warning AF about possible terrorist attack week ago. But generally, I stay with fatal weather conditions/bad luck...

[rogue_blade]

well debris from the crash has been confirmed including a seat, life jacket, bits of metal and jet fuel, other bits and even a turbine or some engine part.

 

Thing is....earlier today they say at first the automated messages sent from the aircraft reported electrical system failures and compression issues.

Now they say the computer reported "complete system failure" and decompression. So that in combination with the lack of any form of mayday call means it must have been a near instant, if not instant catastrophic event. I mean unless all forms of comms were knocked out and things progressed from bad to worse thereafter and the pilots simply had no way of communicating....but I'm thinking the former is what occurred....

 

I am quite baffled as to how it can be so hard to find a downed aircraft. I would assume airlines would have live data feeds of gps co-ordinates their entire flights. And if so, surely they could calculate how far the aircraft could have traveled based of the last gps coordinate received? I honestly have no idea how this stuff works, just thinking out loud here. And apart from GPS what about some other form of satellite tracking, I mean isnt there some sort of satellite to aircraft datalink going on or something, like anything!?

And then this blackbox. We always have to retrieve them and their valuable data which is always a huge task. Why don't these black boxes send a live data stream constantly throughout a flight? Like the same way they recieved the automated messges of the electical and pressuriztion failures?

I don't know, I'm just confused and annoyed as to how it is so difficult to find a crashed jet.

 

This definitely helps answer some of my questions

 

http://edition.cnn.com/2009/TECH/06/03/db.plane.nav.tracking/index.html?iref=mpstoryview

[bumfire]

the lack of SOS suggests a brutal event . it's strange because belonging to experts there are very few chances for lightnings to cause such plane to crash seems the worst lightnings could do is to grill some electrical sytems but on modern planes all electrical systems are doubled or tripled , but the "electrical system failure" is a symptom of a lightning strike or they didn't had luck at all

 

Thats what they want you to think, lightning on an Aircraft can and has ripped huge chunks out of them in the past, some of the pictures I have seen of lightning strike damage is unreal and although I dont think thats what caused this plane to go down, lightning can basically destroy an aircraft given enough volts.

 

Everyone has their theories about what happened, but I suspect that we might never know exactly what caused this one for the simple fact that most of the wreckage is presumed to be at 5000 metres which basically rules out any chance of getting anything back from it without a HUGE operation i.e Glomar Explorer size expedition which sadly isnt going to happen due to the extreme costs involved.

[bumfire]

Whatever, I'm not going to argue my point anymore, if you can't accept that Faraday cages protect aircraft then so be it. What do you expect when 20K amps conducts with thin sheet Alu on a small point? think fuse wire, Here's a link if my words not good enough. The heat damage you see in that pic happens all the time. The important thing here is that the damage is on the outside show me some damage on the inside then you'll get my attention.

 

http://www.popsci.com/breakdown/article/2008-06/electric-aviation-experience

 

A plane is only a faraday cage to a certain point and even then its wishful thinking if you think you are 100% protected in a plane during a strike, although faraday cage does describe the basic theory asto why planes can survive lightning strikes to a certain degree.

 

I would much rather be in a faraday cage on the ground than being up in a plane when lightning strikes for the simple fact that on the ground the cage is earthed and that is the basic principal of a perfect faraday cage, i.e being earthed, a plane in flight is not earthed thus is much more suceptible to powerful lightning strikes which depending on size can totally obliterate it.

[Vault]

lightning can basically destroy an aircraft given enough volts.

 

Volts don't mean a damn thing it's the amperage that causes damage. 250,000 volts at 0.5 amp wouldn't kill you, a perfect example of this is a stun gun, 110 volts at 200 amps will kill you instantly, DC is far worse than AC as well.

 

A plane is only a faraday cage to a certain point and even then its wishful thinking if you think you are 100% protected in a plane during a strike, although faraday cage does describe the basic theory asto why planes can survive lightning strikes to a certain degree.

 

Yeah Faraday got it all wrong. To this day all EMP protected electronics use Faraday cages maybe that's because it's so effective, for the last time you are 100% protected inside a Faraday cage. You are only a conductor in the air, it's exactly why bird's don't get electrocuted when they sit on high voltage high amperage overhead cables, the electricity flows harmlessly through the bird.

 

I would much rather be in a faraday cage on the ground than being up in a plane when lightning strikes for the simple fact that on the ground the cage is earthed and that is the basic principal of a perfect faraday cage, i.e being earthed, a plane in flight is not earthed thus is much more suceptible to powerful lightning strikes which depending on size can totally obliterate it.

 

Lol that's the best comment so far. Now I'd really love to see a lightning strike obliterate an aircraft that uses Faraday's law to protect it. A car has no direct earth because the tyre's are made of rubber which is an insulator, but it's the safest place to be in an electrical storm, because its a faraday cage, bud for your own sake stay away from your mains ok.

[nscode]

Volts don't mean a damn thing it's the amperage that causes damage. 250,000 volts at 0.5 amp wouldn't kill you, a perfect example of this is a stun gun, 110 volts at 200 amps will kill you instantly, DC is far worse than AC as well.

 

You Sir, know absolutly notthing about electricity. :noexpression:

[Vault]

You Sir, know absolutly notthing about electricity. :noexpression:

 

Rather than posting that I don't know nothing about electricity explain what is wrong with that statement.

[X-man]

You are only a conductor in the air, it's exactly why bird's don't get electrocuted when they sit on high voltage high amperage overhead cables, the electricity flows harmlessly through the bird.

No, it doesn't pass through the bird. It simply doesn't enter the bird as the cable is already a better conductor than the birds legs. Only if the bird completes a circuit with the ground or another cable will the electricity go through the bird and most likely toast it.

Edited June 3, 2009 by X-man

[nscode]

Rather than posting that I don't know nothing about electricity explain what is wrong with that statement.

 

I find it bad taste, at least, lecturing Ohm's law on a topic dedicated to an event where people have died.

[EtherealN]

Someone should open a new thread to discuss the electrical matters there.

 

Mainly because I am dying to see a continuation to the debate on it, because I'm learning tonnes here. Or well, at least I hope I'm learning tonnes here. It seems that is part of what's being disputed. What Vault has been saying goes pretty well with my previous understanding of things like this, so if there are errors in there it's errors I would like to see elaborated on.

[GGTharos]

I'm fairly certain that the Faraday Cage works because you have equal voltage throughout the surface of the cage - this means that potential differences inside the cage at least are zero - ie. there is no possibility of current flow from one place to the other due to lack of an imbalance.

 

You can drain this energy - ie. ground the cage. This means that the insulating tyres on a car aren't what make the cage work - Further, the trick here is not to come into contact with the surface that is the cage - at least, according to my minimal understanding of the issue ;)

 

 

Also, what are Faraday's laws? I'm reasonably certain that the effect of a Faraday's cage is explained by Gauss' and Maxwell's equations - but maybe I recall incorrectly.

 

Rather than posting that I don't know nothing about electricity explain what is wrong with that statement.

[Pilotasso]

Only journalists think and advanced with the theory Lighnings brought it down. Judging by the recieved electronic failiure reports (now it apears that structural warnings were also recieved) and that the pilots never had time to issue an SOS, apears a sudden explosive end to the plane. A bolt wouldnt do that.

[X-man]

Only journalists think and advanced with the theory Lighnings brought it down. Judging by the recieved electronic failiure reports (now it apears that structural warnings were also recieved) and that the pilots never had time to issue an SOS, apears a sudden explosive end to the plane. A bolt wouldnt do that.

Might not be the sole cause, but it could have contributed to the situation...

 

There is a large oil spill close to the wreckage which makes me think if there was an explosion at all. Wouldn't most of the fuel have been ignited or at least burnt on the surface?

Edited June 3, 2009 by X-man

[Vault]

nscode volts and amps are bound to each other as Ohm's law states but it is amps that kills. Forgot too add the reason why DC is more dangerous. https://www.scienceforums.net/forum/showthread.php?t=4774

 

50,000 volts with 133mA wont kill you. If you want a bit more precision increase the amps to probably 500Ma and your a dead man, It was just an example for arguments sake.

 

http://www.tbotech.com/taser-specifications.htm

 

X-man I can admit when I'm wrong and you're right that was a piss poor example.

 

GGT it's a typo I meant cage.

Edited June 4, 2009 by Vault

[bumfire]

ah NVM, this isnt a thread to be debating whether lighting can destroy and enter aircraft.

 

R.I.P to all those that were lost and hopefully we may get to find out the cause so that it can be prevented in future.

Edited June 4, 2009 by bumfire

[Vault]

Dude, I am sorry if everyone here thinks your wrong and your the only one who thinks your right, I cant help it, but REAL PILOTS disagree with you, even those who fly PAX Liners for a living...

 

Who cares who thinks I'm wrong or right. I don't. :)

 

FARADAY works on the principle of it being GROUNDED to provide maximum protection, you are not grounded up in the air so you are not in a complete faraday cage, its the best they can do with the limitations they have to work with, disagree all you like but until a faraday cage is grounded it isnt 100% fool proof as you seem to think, if you seem to think that all electricty strikes cant penetrate aircraft then you are sadly mistaken, I have pics of lighting strikes that have made a hole in one part of the aircraft and then came out the opposite side, burnt straight through exterior/interior walls, but according to you that could never happen because in a faraday cage you are protected against lightning and as such it never gets into the inside, MANY pilots will also refute your claims of it never being able to happen.

 

The aircraft with the protection of a Faraday cage will always ground because if it couldn't ground it wouldn't strike the aircraft, electricity will always take the shortest route with the least resistance.

 

Also, A large enough lightning strike can destroy an aircraft, all it needs to do is hit the fuel tanks and bingo or like in other pics I have seen where control surfaces have been totally destroyed, which could render an aircraft unflyable.

 

Not in modern day commercial aircraft, like the Airbus in question considering on average each commercial airline gets hit by lightning once a year they should be dropping out of the skies. Is there any chance of a link to those pictures of aircraft with missing control surfaces from ESD strikes.

 

If it wasnt for the rubber fuel tanks in the wing, one plane very well might of had that happen, the pilot comments about it himself on pprune, upon inspection the upper skin of the wing had a hole burnt through the top, the inside of the wing was melted in parts and all around the circumference of the tanks was scorched and their was an exit hole on the lower outer skin of the wing, those rubber fuel bags probably saved that plane from disaster, but again, according to you that is impossible because its a faraday cage and such things cannot happen in a faraday cage.

 

Yes they probably did save it that's why those insulation liners are there. When ESD conducts with the aluminium shell of a modern commercial aircraft I'd expect to see arcing, pitting and burning and small holes. According to me? naaa according to Faraday.

 

Certain types of rarely encountered lightning can destroy aircraft due to the immense energy involved, they are rare but aircraft safety standards doesnt require for those types of strikes to be taken into account when building aircraft, i am sure you can be able to find the type i speak on by googling, thus the protection that planes have will not work against those types of strikes due to the immense amount of energy involved, ok they are rare and unlikely to happen to any degree and it probably isnt viable to protect against it, but it is known about and IT CAN HAPPEN but just not enough for anyone to worry about it..

 

I looked but couldn't find a thing, have you got a link for that information?

 

Again, a faraday cage needs a DIRECT connection to ground to make it somewhat immune to lightning that hits it within reason..

 

Again, ESD will ALWAYS ground from an aircraft that uses a Faraday's cage for protection. It is IMPOSSIBLE for it not too.

 

You ever seen pictures of cars destroyed by lightning strikes ??? not as uncommon as you may think.

 

None that are made of metal.

 

Quoted from a pilot who flies airliners:

 

I know from personal experience, that a 'bolt' can enter an aircraft. The light intensity, once the sheath has been irradiated away, would saturate then destroy the fiber data-lines.

 

A discharge goes much where it wants. My biggest went in what became a 4" hole in the top of the wing, round the rubber fuel bags, and out a similar hole - in line with the top hole. I'm under no illusion that if the 'bolt' had been more vigorous, we'd have lost the wing in moments.

 

End quote

 

ESD will always go the shortest route with the less resistance. If the bolt entered the interiour of the aircraft he'd be dead, Are you sure that by entered he didn't mean struck?, Now I'd beleive turbulence could take the wing off an aircraft but a lightning bolt??? wtf!.

Edited June 4, 2009 by Vault