Air France jet vanishes from radar

[RvETito]

AirTito, any idea on who is going to investigate it? I know in the USA the NTSB investigates such incidents.

 

Assuming the aircraft has dissappeared/crashed in international water it's all under French BEA's jurisdiction. It's the french analogue of NTSB in US.

 

Forget about the lightning, it can't hit it at FL 350. Even if so, the flight control computers will not go nuts all together. I'm not familiar with the 330 but the 319/320/321 have 7 dual-channel primary flight control computers for ailerons, elevators/THS, spoilers and yaw damper plus hydro-mechanical control of the rudder and mechanical backup control of the trimmable horizontal stabilizer (THS). So even in case of total electrical failure there is still control.

 

Also, they've reported short circuit- a lightning can't cause a short circuit. Instant overload/damage of some systems might occur but not fire. Since they've been able to transmit this message (assuming the info about it is correct) that means they've had the time to do it. Electrical failure leading to short circuit is possible, also a fire as a result is quiet possible as well. Or like the TWA 747 I posted- short circuit of wires in the center tank- BANG!

 

This is much more possible than this lightning story. I expect both Air France and Airbus will blaim the weather until otherwise proven. Air France will not admit that their flight/ground crew have made a mistake, neither Airbus will admit that their airplane is faulty. Not until they collect any useable data of what actualy has happened. If they find anything at all...

Edited June 1, 2009 by =RvE=Tito

[GGTharos]

Yeah, that last part is the sucks :(

 

Thanks for the info.

[Vault]

A lightning could cause rupture/burn outs both on metalic or composite structure. There are no recorded cases of lightning strikes that have led to structural damage of such a magnitude that could down a plane. It mostly affects avionics and especialy radio nav/comm equipement. Because all components of the plane are electrically bonded (equalized electrical potentials) the charge will go through the entire plane and go out through the static dischargers and various antennas. There might be an instant electrical overload but that's why you have circuit brakers on all systems (mulitple CB's for essential systems like flight control computers for example).

 

I don't buy this lightning story at all. Long before the 3rd hour of the flight when contact has been lost the aircraft has been flying at flight level where lightnings are not happening. Even we assume some huge CB cloud in the middle of the ocean they've had plenty of time to detect it and fly around it.

 

I don't buy it either, that Airbus has a faraday cage that's intergrated into the fuselage, wings and engines. All avionics and critical systems are contained within the protection of the faraday cage too, that Airbus should be impervious to any type of ESD.

[-fox-]

I expect both Air France and Airbus will blaim the weather until otherwise proven. Air France will not admit that their flight/ground crew have made a mistake, neither Airbus will admit that their airplane is faulty. Not until they collect any useable data of what actualy has happened. If they find anything at all...

 

That sounds quite likely.

[X-man]

Forget about the lightning, it can't hit it at FL 350.

I beg to differ. There were severe CBs in across the part of the ocean where AF447 passed. CBs were recorded to be as high as FL500.

 

The plane had just passed outside Brazilian radar coverage and heading for the storms. Maybe their WX-radar was malfunctioning or maybe they didnt check it. This was i the middle of the night, so it's quite plausible that the flight might have entered the CBs and experienced severe lightning and turbulence. We musnt rule out any possibilities yet.

 

As long as there isnt a wreckage to examine, we cant say for sure what it was. Sudden decompression, Lightning, Turbulence, Fire, Power failure, terrorists etc could be anything, though it sure looks like a very sudden, catastrophic event since the pilots didnt have time to report anything to the controllers. Only thing that was sent was an automatic maintenance message stating several malfunctions to electrical and pressurized systems.

Edited June 1, 2009 by X-man

[nscode]

It's not ours to rule out or confirm anything.

 

Btw, a few days ago I was on the roof when lightning struck a lighthing rod on that roof 5m from me. Unique feeling. Made my hair go up. The funny thing is, the router (PC based) on the roof, grounded by that lighnig rod didn't even reboot, let alone fry. On the other hand, we've had noumerous failures on our equipment during lighning storms when it was kilometers away.. You never know with lightning..

[Vault]

I beg to differ. There were severe CBs in across the part of the ocean where AF447 passed. CBs were recorded to be as high as FL500.

 

The plane had just passed outside Brazilian radar coverage and heading for the storms. Maybe their WX-radar was malfunctioning or maybe they didnt check it. This was i the middle of the night, so it's quite plausible that the flight might have entered the CBs and experienced severe lightning and turbulence.

 

Maybe the wiring wasnt 100% coverd or what not. Should the lightning enter, the electronics could get fried very easily. We musnt rule out any possibilities yet.

 

As long as there isnt a wreckage to examine, we cant say for sure what it was. Sudden decompression, Lightning, Turbulence, Fire, Power failure, terrorists etc could be anything...

 

You cannot earth ESD on the innerface of a Faraday cage because it's impossible, it's just a conductor, it has no earth so it cannot earth, it's the reason why sitting in your car is the safest place in an electrical storm. The clip below shows the plane acting as a conductor. That Airbus should be bombproof against ESD.

 

[X-man]

Yes, theoretically, this is what's suppose to happen and probably does happen 99.99% of the time. However, the real world have quite a few extra variables then all the formulas and theories which makes things very hard to predict.

 

I read a story about an E-3 with the USAF which was doing a normal training flight when it was hit by lightning. The whole thing went dark. Fortunately, the 707 is not FBw (hell, not even hydraulics) so the crew was able to put her down safely. Now Im no expert in the field and I dont know all the circumstances about the E-3 incident, but it did occur for whatever reason. So Id be more humble then just ruling it out as "bombproof against ESD"

[Vault]

Yes, theoretically, this is what's suppose to happen and probably does happen 99.99% of the time. However, the real world have quite a few extra variables then all the formulas and theories which makes things very hard to predict.

 

I read a story about an E-3 with the USAF which was doing a normal training flight when it was hit by lightning. The whole thing went dark. Fortunately, the 707 is not FBw (hell, not even hydraulics) so the crew was able to put her down safely. Now Im no expert in the field and I dont know all the circumstances about the E-3 incident, but it did occur for whatever reason. So Id be more humble then just ruling it out as "bombproof against ESD"

 

Seriously mate I'm not being argumentative but it's impossible, A faraday cage cannot earth on the innerside because it has no earth, all positive currents conduct from the closest point and the closest point of a faraday cage to earth is the outerside making it physically impossible, The only damage you can get from an ESD strike on a faraday cage is burn marks on the positive and ground entry and exit points which are negligible to commercial aircraft.

[topol-m]

I`ve digged a little bit and it seems physical damage caused by lightning is really rare to observe, and when present its often result of the fire caused by the lightning. But nonetheless there are cases of physical damage caused directly by it - an example with a photo of the damaged plane:

http://www.dailymail.co.uk/news/article-513525/Terror-10-000ft-lightning-strikes-jet-en-route-Gatwick.html

[Vault]

I`ve digged a little bit and it seems physical damage caused by lightning is really rare to observe, and when present its often result of the fire caused by the lightning. But nonetheless there are cases of physical damage caused directly by it - an example with a photo of the damaged plane:

http://www.dailymail.co.uk/news/article-513525/Terror-10-000ft-lightning-strikes-jet-en-route-Gatwick.html

 

It's a GRP nosecone, GRP is a poor conductor, That GRP nosecone is not part of the faraday cage and offers little protection. By looking at that picture it looks as though the ESD bolt has penetrated strait through the GRP nosecone and conducted onto the airframe below. Either way the flight control computer is not at risk, a conductor on the outside of a Faraday cage like a radar antenna and flight instruments are.

Edited June 2, 2009 by Vault

[X-man]

Seriously mate I'm not being argumentative but it's impossible, A faraday cage cannot earth on the innerside because it has no earth, all positive currents conduct from the closest point and the closest point of a faraday cage to earth is the outerside making it physically impossible, The only damage you can get from an ESD strike on a faraday cage is burn marks on the positive and ground entry and exit points which are negligible to commercial aircraft.

 

Ok, I get you. But could the lightning have other effects which can cause a blackout of the system of the aircraft, or even structural failure? What a weak spots in the fuselage, Could there be any physical damage?

[159th_Viper]

.

 

Probable accident location, pending confirmation, off Senegal Coast. Reports of wreckage found at said location.

 

Link

[theGozr]

Sad news :( Terrible..

[Shaman]

Forget about the lightning, it can't hit it at FL 350

 

Tropical thunderstorms tops reach 50.000 feet, and that's where all storms are electrically charged.

 

So... if tops of any storm receive also the highest charge... if the a/c went through while at ~35000 feet, it was lightning hell.

Edited June 2, 2009 by Shaman

[sniffer]

Ok, I get you. But could the lightning have other effects which can cause a blackout of the system of the aircraft, or even structural failure? What a weak spots in the fuselage, Could there be any physical damage?

 

Faraday...whatever... it can be that way eg.

 

:( R.I.P.

[Vault]

Faraday...whatever... it can be that way eg.

 

:( R.I.P.

 

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

[topol-m]

Faraday...whatever... it can be that way eg.

 

:( R.I.P.

 

The case here is different. The NTSB federal agency:

ASA Airlines flight 5533, a Bombardier CRJ-200, experienced a cockpit fire on the ground shortly after external power was applied to the airplane in preparation for flight. The captain and one flight attendant evacuated the airplane via an airstair without injuries. They were the only individuals on the airplane at the time. The fire department extinguished the fire after it had burned an approximate 18 inch hole through the left upper cockpit crown skin. The flight, intended to be conducted as Code of Federal Regulations (CFR) Part 121 scheduled service, was to be flown from Tallahassee Regional Airport (TLH), Tallahassee, Florida, to Hartsfield Jackson Atlanta International Airport (ATL), Atlanta, Georgia.

Edited June 2, 2009 by topol-m

[wickedpenguin]

I'm so sad to hear this.

 

I highly doubt it was lightning. Honestly, there are so many possibilities. Extreme turbulence. Electrical fire. Explosive decompression. Terrorism. Failure/icing/blockage of pitot tubes, leading to incorrect readings. Faulty radar readout.

 

A modern airliner is a complex beast with a ton of redundancy. However, small issues tend to multiply themselves.

 

What bothers me the most is that whatever happened, happened so quickly that the aircraft was not able to transmit a mayday. To me, that speaks of an explosion, explosive decompression, or catastrophic airframe failure. Or, something like an uncommanded flat/slat deployment or control surface actuation could have the crew fighting an aircraft suddenly out of control. Enough speed or G-forces could tear the aircraft apart.

[-fox-]

They now say the automatic failure report that has been mentioned earlier read that all systems were offline for full three minutes before the message was sent.

[X-man]

What about positive lightning? http://en.wikipedia.org/wiki/Positive_lightning#Positive_lightning

[RvETito]

Tropical thunderstorms tops reach 50.000 feet, and that's where all storms are electrically charged.

 

So... if tops of any storm receive also the highest charge... if the a/c went through while at ~35000 feet, it was lightning hell.

 

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.

[-fox-]

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.

 

Actually they say it is possible that the pilots tried to do just that. The discrepancy between their last known location and the debris seems to indicate it, if I understand it correctly.

[topol-m]

What about positive lightning? http://en.wikipedia.org/wiki/Positive_lightning#Positive_lightning

 

:thumbup: Never knew such existed. You`ve just improved my knowledge of lightnings. Considering their power and that the planes are not constructed to withstand that amount of energy its pretty possible to inflict serious damage to a plane, very bad luck, but possible.

[sniffer]

Whatever, I'm not going to argue my point anymore, if you can't accept that Faraday cages protect aircraft then so be it.

I understand it very well but my point is that isn't 100% protection... and it's easier to me believe in thunderstrike causing a lot of malfunctions than bomb on the board (we'll see cause 30 min. ago they talked about not excluding terrorist attack). Please, don't treat it like trying to argue cause I've got enough guys screaming about what board number plane got or if it was bermuda triangle (read such things on my country aviation forums :doh:).

Sure is that a lot of people have big tragedy now and a lot of people had gone...