Air France Plane down

Originally posted by sy.gunson
Aircraft skins are bonded so that lightning travels around them, not through them. It's called a Faraday's cage. Lightning is not the cause.

Lightning does generally stay on the outer surface.............on a perfect structure, meaning no rivet heads slightly raised, no inperfections in paint, perfectly sealed seams, etc. Lightning can and does enter the systems of an aircraft all the time. Lightning will travel completely smooth over a smooth surface but when it encounters an imperfection it will choose the path of least resistance(it's electricity after all) If there is a slight paint crack around a rivet then the lightning has an opening to bare metal, and trust me, bare metal conducts electricity a lot better than the painted surface. On modern airplanes, even the newer ones with lots of composite materials and bonded surfaces, there is a lot of metal holding it all together.

In regards to locator beacons. Each country has different requirements for placement of locator beacons but in general I can tell you that there would be multiple on that aircraft. Generally there is going to be one near the tail of the airplane. It is waterproof to very deep depths, it operates on it's own battery source, and it's location is picked based on where it might survive a crash. The tail usually being the last part to hit the ground and historically tail sections are fairly intact after crashes. Though I admit, a bomb in it's vicinity would destroy it.

A second transmitter is located on the "black box" this it generally near the cockpit at the front of the plane. This pinger is designed to withstand just about anything, deep water depths, fire, explosions, etc. It too has a self contained power source independent of the airplane systems. I've seen the testing at the manufacture of one brand of these transmitters, there is a reason it's the one strapped to the "black box".

Obviously though, the deeper the transmitter is in water, the weaker the signal, the closer the search crews will need to be to locate it.

[edit on 2-6-2009 by maxweljames]

Originally posted by maxweljames

Obviously though, the deeper the transmitter is in water, the weaker the signal, the closer the search crews will need to be to locate it.

[edit on 2-6-2009 by maxweljames]

How deep will the signal still work though?

The Senegal Government is saying that they have found some wreckage in their waters and that they believe that most of the plane is now at the bottom of the sea, the area they say it is in is at least 4,000 meters.

That’s pretty deep, could the signal still work that far down?

Mikey


[edit on 2/6/2009 by Mikey84]

Last March during that snow storm where Atlanta got like 4 inches of snow I was in a plane flying from Boston to Atlanta that got struck by lightning . I happened to be looking out the window as it hit the wing , basically i seen a flash a loud boom and a spark on the wing.

Planes get struck very often and are designed to but i would assume that it could take a plane down after experiencing how powerful lightning hits.

Originally posted by Mikey84


How deep will the signal still work though?

The Senegal Government is saying that they have found some wreckage in their waters and that they believe that most of the plane is now at the bottom of the sea, the area they say it is in is at least 4,000 meters.

That’s pretty deep, could the signal still work that far down?

Mikey
[edit on 2/6/2009 by Mikey84]

According to a danish TV-station, the signal from a black box can be detected from a depth of 6 kilometers.

Translated Source

Hi all, new member posting here.

Just to clarify the length of my avionics knowledge runs to what I have learned watchung air crash investigation and similar, no more than that.

As far as I am aware these beacons last for 30 days, assuming they werent damaged in the accident.

Someone above posted that lightning strikes can leave pin prick holes in the fusalage. Well, if in the wings, thats fine as only the human carrying areas are pressurised I believe. Maybe lightning struck through the main passenger area and caused a tiny hole, causing a sudden explosive decompression.

Fly by wire is useless if the wires get severed in some way, and explosive decompression can cause that easily.

Maybe it was a side effect of a lightning strike, rather than being caused by it as almost all modern planes are "lighning proof".

Best wishes to all those involved directly or indirectly and hopefully they will find some people alive when they find the wreckage.

reply to post by PGRacer


I don't buy the lightning theories, especially after seeing these videos:



And this one:

www.metacafe.com...

You can see in both videos huge lightning hits both large aircraft in flight with no problems resulting.

With this now missing plane something happened, and it was so bad that the crew didn't have time to send a radio message or any transmission out.

It will be interesting to see what they find in the wreckage and especially what is on the flight recorders.

Until then it is all speculation and conjecture.

reply to post by Mindsmog


It's a game when people start talking about Atlantic Anomoly. Another person started talking about a psychic vision that it had landed on an Island in the Caribbean. Others talked about passengers texting as the plane was going down.

That's just cruel trivialising.

If you think trivialising the loss, hurt and pain to get some entertainment value from this thread is acceptable then your opinion doesn't impress me much.





[edit on 2-6-2009 by sy.gunson]

Originally posted by sy.gunson
Aircraft skins are bonded so that lightning travels around them, not through them. It's called a Faraday's cage. Lightning is not the cause.

Not with positive lightning. Sorry to keep beating this drum, but it needs to be repeated because people just aren't getting it. Aircraft have been designed to withstand most strikes by negative lightning. Positive lightning is far too powerful to defend against. As it is relatively rare, most airlines don't even bother with the costly upgrade attempts and play the odds against a strike.

[edit on 6/2/09 by larphillips]

Wreckage Spotted' In Hunt For Airliner

The Brazilian jets searching for an Air France airliner that vanished over the Atlantic Ocean have reportedly spotted plane wreckage.

The South American country's air force found debris 390 or 1,000 miles off its coast, depending on reports.

The wreckage included airplane seats that were floating in the sea along the path that a missing Air France jet was flying.

Air Force spokesman Jorge Amaral said authorities cannot immediately confirm the seats were from the missing plane.

Also spotted were small white pieces of material that may be metallic and signs of oil and kerosene, which is used as jet fuel.

The debris was found north east of the Brazilian archipelago of Fernando de Noronha.

The plane disappeared with 228 people aboard.

Sky News

Mikey

[edit on 2/6/2009 by Mikey84]

I don't buy the lightning theories, especially after seeing these videos:

I agree its increadibly unlikely, and if it is lightning then its is probably a combination of lightning and something else, but at this stage it seems to be the strongest piece of evidence available.

All signs point to a sudden decompression whether caused by lightning, a bomb, mechanical failure, or some other way I am not aware of (like I said Im not entirely au fait with avionics).

Bomb doesnt seem to fit, especially as no media have jumped on the idea as yet, who would be first to sensationalize the whole affair to sell papers.

Mechanical failure is possible but with the number of redundancies an A330 has, again this is unlikely. Just leaving the lightning.

Of course there is the possibility that it was taken down by a UFO, or hit a wormhole, or a weird electromagnetic effect from earth or sun. But To be honest, I think those possibilities are a bit mad. Not saying I dont belive in UFO's, but I think that linking this crash with UFO's only serves to belittle conspiracy theories and theorists to the wider audience.

Show me a picture or video of it being taken down by a UFO and I'll gladly change my mind. Until then I think we'll leave UFO as a last resort.

Facts
Aviation safety statistics indicate that each large passenger jet — such as the Airbus A330 — is struck by lightning about once every three years on average. Regional aircraft however, which fly at lower altitudes, are hit more frequently — about once a year.

Although lightning may have been a contributing factor in a handful of accidents since World War II, only one major crash was attributed directly to a strike. In 1963, a Pan American World Airways Boeing 707 exploded in midair when its fuel tank fumes were ignited by lightning.

To avoid structural damage, both military and civilian pilots use standard onboard radar to maneuver around the thunderheads, which are characterized by electrical discharges, hail and high winds.

The mid-Atlantic region is where most hurricanes that hit the Western Hemisphere originate, and this is the beginning of the storm season. Thunderheads in the area can tower up to 60,000 feet, making it impossible for airliners to fly over them and forcing them to make long diversions

Air France reported that the aircraft's ACARS (Aircraft Communications and Addressing System) — a digital datalink that automatically transmits service messages from the aircraft to ground stations — messaged the company's headquarters regarding a problem with the aircraft's electrical and pressurization systems.

With only these facts in hand we can assume they probably were not on their posted flight path as the pilots of the Air France Airbus reported that they had encountered an area of intense cumulonimbus activity. How far off course they were depends on how big the storm was...
anything more is anyone's best guess? heck maybe the "Island" took then and they hanging out with Locke and Jack right now?

that is a picture of positive lightning - man MANY times more destructive (and many timea rarer) than negative lightning.

BBC are reporting Debris found in the Atlantic 650km NE of Fernando de noronha island. On the world news channel.

news.bbc.co.uk...

Brazilian aircraft searching for an Air France jet which went missing with 228 people aboard in an Atlantic storm have spotted debris on the ocean.

Plane seats and other items were sighted 650km (400 miles) north-east of Brazil's Fernando do Noronha island, the Brazilian air force said.

Notice how the media never even came up with terrorism, so i think you guys should leave that be, and forget about stupid shows like lost or bermuda triangle on this.

Stuff happens.

Here's a (some) nice PDF file on lightning strikes...

FAA Lightning

PROTECTIO N OF AIRCRAFT FUEL SYSTEMS AGAINST FUEL VAPOR IGNITION CAUSED BY LIGHTNING

I find the lightning hypothesis extremely unlikely.



[edit on 2/6/2009 by C0bzz]

BBC report that at 0200GMT the Captain used the ACARS system to text notification that he was amongst CB, towering thunderclouds. Last automated transmission was at 0214GMT.

New information provided by sources within Air France suggests, that the ACARS messages of system failures started to arrive at 02:10GMT indicating, that the autopilot had disengaged and the fly by wire system had changed to alternate law.

Between 02:11GMT and 02:13GMT a flurry of messages regarding ADIRU and ISIS faults arrived. (failures of the autopilot guidance system)

At 02:13GMT PRIM 1 and SEC 1 faults were indicated (electrical failures)

At 02:14GMT the last message received was an advisory regarding cabin vertical speed.


Incidentally it just occurs to me that there is a CB in my avatar photo to the right background of the plane.



[edit on 2-6-2009 by sy.gunson]

reply to post by sy.gunson


Can you advise what Cabin Vertical Speed means in Layman's terms please?

As in bucking bronco... mad roller coaster ride... rough as guts... shake out your false teeth etc