Lightening Strike
 

I totally agree, it is nearly impossible that this aircraft has been downed by a lightnening strike although I will not rule out that the aircraft entered a CB. Since the incident happened close to the equator and ITCZ the tropopause is higher and thus CB tops can be recorded at very high altitudes were as normally airlines flying in mid latitudes will fly above any weather. Although I cannot understand how the crew could have flown directly into CB with AWB onboard indicating severe turbulance and weather.

Kinda hard to float when you're buried under a few tons of fuselage.

Come on people. Enough with the stupid questions already.

The A330 ATSU needs AC1 BUS as its power source so if they got an ACARS downlink it would seem to indicate that at least AC1 was powered hence it could mean that at the time the message was downlinked, the electrical system was not as degraded as it would be, for e.g., in an EMER ELEC CONFIG.

Jotape, have a look here:

Airline accident ratings

The reason I don't wish to speculate is because in the bigger picture, we know nothing. With respect to our fellow aviators the gadgets we get to play with are pretty impressive. Especially for en-route weather.

Which is why I'm not going to just agree with some ill-thought theory that the plane happened to fly into a CB. As with ALL flight accidents, there is a chain of events. What we will find out is that many things went wrong in order for this unfortunate event to occur, not just one thing.

Lightning grounding testing for composite aircraft?
 

A lightning strike on a North Sea helicopter a number of years ago brought down the aircraft. Luckily the crew and oil workers were rescued. These North Sea helicopters had been hit regularly by lightning over a number of years with no major damage or problems. But it was not until after the manufacturer added composite tail rotor blades that a theory developed that composite materials could be exploded by rare and extremely powerful lightning bolts. The A330 as I understand is made of 12-15% composite material. Nowhere near what the A350 or 787 Dreamliner will be, but what I read on the net suggests lightning protection is difficult to incorporate into a composite aircraft compared to conventional aluminium ones. Composite airframes also give less electromagnetic shielding compared to aluminium, making it more difficult to protect avionic systems.

Lightening Strike
 

To F117A:

Just suppose that they continue after an ELEC failure. Would they still have WX Radar indications?

It's all speculations, at this time all we sadly can hope for is to find the FDR and get clues from it.

WHBM, the crew have the authority to do whatever they need to do to keep the aircraft safe. I am sure they will have been picking their way through the weather without fear of a reprimand following a tech stop (if required) for extra fuel. Although after reading the weather I am sure they took plenty of gas and could have meandered around all day avoiding stuff without eating into reserves!

Brazilian Air Force press release
 

(Exact translation of text received via a news site; the Air Force site seems to have buckled under the traffic.)

The Brazilian Air Force Command informs that it has begun search operations for AIR FRANCE FLIGHT 447, which disappeared when flying from Rio de Janeiro, Brazil to Paris, France, with an estimated arrival time of 6:10 AM (Brasilia time).

The AIR FRANCE aircraft took off from Galeão Airport in Rio at 7:30 PM local time. At 10:30 PM, Flight AFR 447 made its last contact via radio with the Atlantic Area Control Center (CINDACTA III) at position INTOL (565 kilometers from the city of Natal, RN), informing that it was entering the airspace of DAKAR - Senegal (position TASIL – 1,228 km from Natal), at 11:20 PM (Brasilia time). At 10:48 PM, when the aircraft left CINDACTA III's radar coverage, at the island of Fernando de Noronha, information indicated that the aircraft was flying normally at an altitude of 35,000 feet (11 km) and at a velocity of 453 knots (840 km/h).

At the time estimated for position TASIL (11:20 PM), the AIR FRANCE aircraft did not make the expected radio contact with CINDACTA III, of which DAKAR Control was informed.

AIR FRANCE informed CINDACTA III, at 8:30 AM, Brasilia time, that at approximately 100 km from position TASIL, flight AFR 447 sent a message informing the company of mechanical problems on the aircraft (loss of pressurization and a failure in the electrical system).

At 2:30 AM local time, SALVAERO Recife activated search teams of the Brazilian Air Force - FAB, with one C-130 Hercules aircraft, one sea patrol P-95 Bandeirante and the Air-Land Rescue Squadron (PARASAR).

Once airborne, the crew have complete authority to do anything they consider necessary for the safe conduct of the flight - including returning to the point of origin. They may need to justify their actions later, but fear of reprimand would be very far from their minds when making a safe flight decision.

The amount of composites in the A330 fuselage structure is negligable.

With regards to recovery, a typical N Sea spec WROV can operate down to approx 2500m and is capable of tasks such as recovering a FDR. There are a number of vessels operating on construction projects in W Africa at the moment equipped with such ROV's, any deeper than that however is getting very specialist.

Even so, recovering a whole aircraft from that depth is one heck of a feet and I would suggest extremely unlikely due to the massive costs involved. A hi-res multibean mapping of the debris field along with a visual ROV inspection of key areas and recovery of the FDR would be more likely.
Fingers crossed it doesnt happen like that and by the grace of god they find the kite merrily floating on the surface with all the pax and crew safe and well.

It depends what type of electrical failure. But for sure to have a total blackout is really something rare. The A330 is equiped with quadriplex elec systems all independent of each other. On rare occasions a total black out can occur if all engines fail. At this point a RAT is deployed to give limited elec to hydraulics and minimum avionics.

We can assume that at the time of the accident there was other traffic in the area going northbound. The three parallel South Atlantic ATS routes are not heavily but frequently flown. Any distress calls on 121.5 would have been certainly heard by someone else. VHF is extended range up to 400 or 500 NM from the receivers in the area and Recife and Sal can listen far out. Also other traffic would have experienced the CB area yesterday night on the same airway, most likely also at the same flight level 350.

Of course all we can do is speculate and make educated guesses at this stage, but having read many of the previous postings on this subject, I am suprised that the "T" word (terrorism) hasn't been mentioned more often as a theory today?

As much as we would like to brush this aside, I am sure that "radical groups", especially AQ etc are not considered a threat in south america, and perhaps the terrorists have realised this too and have managed to breach security in Rio?

Let's hope not!

CDG1
 

You raise a good point but....
Think back to Lockerbie. A sudden, disastrous in-flight break-up. There was no time for a radio message before the flight crew were incapacitated. There have been many similar incidents.
Here we have a bad weather system up to 41,000 feet (look at the previous posts herein) - a lot higher than this aircraft was probably at. It was night so there would be no visual indication of Cu Nim (CB). The dangers of CAT are already well known. Then the aircraft runs into the equivalent of Mother Natures sledge hammer including (perhaps) a major lightning strike that severely effects the electrical systems including the weather radar and, more crucially, the auto-pilot - something you really do not want at FL350 or higher.
Aircraft out of control, at high speed (Mach .83+?) no means of communication, little means of regaining manual control. The airframe begins to rapidly break up.
It's a minus situation for even the best of pilots.
Conjecture? Sure it's conjecture. But what else are we likely to have here unless, by some miracle, the 'boxes' are recovered.

To be honest, I'm glad it hasn't been. A tiny fraction of aviation incidents are terrorism related, and to go along that train of thought in a case like this is completely unfounded.
Also, it's hardly a terrorist coup to have a plane crash into the middle of the Atlantic Ocean - just devastating to those who have family and friends unaccounted for.

For me, personally who has sat at my laptop in the garden on my day off and reading copious amounts of news, things simply do not add up. Which is why speculation must be kept to a minimum.

The reasons could go from Terrorism (which someone alluded to has not been mentioned much) to the Bermuda Triangle (which hasn't been mentioned if you believe in that sort of BS.

People have mentioned about the weather at the time and any weather that can bring down an airliner will be seen on any en-route weather information system so I don't buy that as one single or most important cause.

Was it on a busy route? Was BA/KLM/Iberia also flying to europe last night. I wonder what conditions they encountered?

:ugh:
Why are you surprised?
There has been NOTHING to suggest that this was a terrorist act. No terroist organizations have claimed responsibility. The airline was not advised of any threats to their aircraft.

Why try to stir up speculation that NONE of the (limited) available information can support? Fear-mongering is all you're doing.

Do we know if any other traffic was in the area at around that time, to confirm weather conditions?

Is it really possible for weather to bring down a big jet like this? How extreme would the conditions have to be?

Here on the telly in BKK, Richard Quest of CNN International is reporting a statement from the Brazilian Air Force indicating a report of "loss of pressure" from the "automated system" aboard the plane (presumably ACARS).

This is said to be in addition to the reports of turbulence and a short circuit in the electrics. The implication of the story is loss of cabin pressure, though I know how the media can get things wrong, especially when translating technical material from other languages is involved.

No fan of RQ here, and I have to consider the source. I mention it only because it's something I haven't heard reported thus far. (I am only reporting, and not speculating.)

1) did any of the other aircraft on the route of flight report severe turbulence? (there would have been a string of aircraft from Brazil to Europe that night).

2) WX Radar only shows precipitation and not turbulence.

3) No crew in their right mind would fly into severe turbulence if they knew it was there.

4) I was booked onto that plane a week from now. When I found out I was booked Air France a few days ago, I changed my ticket to another airline due to past experiences with flying Air France from CDG to Rio. Once it took 48 hrs to get to Rio due to technical problems.....(complete blackout as the aeroplane taxied out onto the runway late one foggy night - 5 "tries" later the passengers rebelled and refused to fly on the aeroplane - was a different aeroplane make and model so unconnected with this incident).

There is lots of discussions about weather maps a speculation about the conditions in the vicinity of the last known postion, although does anyone know if there were any other aircraft following the same or parallel routes that experienced turbulence, CBs or other.

If this was the second AF flight from Rio to CDG, what routing did the first flight take and what en-route weather was experienced?

I am not speculating (famous last words before I get flamed ;) ) I just feel that putting a map up and saying "ooo looks bad" and getting a confirmed report from another aircraft in the same bit of sky are two completely different things in understanding what weather the aircraft experienced.

Pyro

Air France's statement says it was a lightning strike, you would expect them to know wouldn't you?

I find the reports of electrical and pressurization problems reported to maintenance (at the same time??) to be interesting. Can anyone see a VERY strong and well aimed bolt holing the skin? Purely a hypothetical question only, but if I wonder it, others must also.

To clarify the post above from Xeque, hand flying an Airbus fly by wire at high altitude is very easy in normal law, the loss of an autopilot is of no concern.

is what I read, correct me if I'm wrong, but how is a spokesperson supposed to point out facts from where he/she is located at the moment?
"may" does not mean it is fact.

I didn't come onto this thread to argue about technicalities in what I'm saying.

French Sources Say Lightning Was the Probable Cause
 

From 20Minutes:
Disparition d'un avion Air France: «aucun espoir», le PDG évoque l'hypothèse de la foudre sur 20minutes.fr

Selon Air France, la foudre pourrait être à l'origine de l'accident...

En milieu de journée, le directeur de la communication d’Air France a déclaré que l’hypothèse la plus vraisemblable était que l’avion ait été «foudroyé». L'avion avait subi un contrôle technique sans problème le 7 avril.

According to Air France, lightning could be at the root of the accident.

The communications director of Air France declared that the most likely cause of the crash was that the plane had been "blasted" (by lightning) in the middle of the flight.

electrical failure
 

Disclaimer: Not an expert nor pilot

If there were a fatal and total electrical failure - than the system certainly would not have been able to send out a message about it, at least not at that time, would it? As this requires some sort of amps/voltage...?

I will not speculate on this accident. What I will say to those who comment about, or ask about, the "black boxes"is this: The recorders will be found and retrieved, and it will not be by "a miracle". The cause will most likely eventually be established, reported on, and accepted by most experts.

Loss of AP is one thing, but what of loss of electrics altogether? I've heard A320 pilots refer to it as "Sparky" because if electrics are lost, it becomes a lawn dart. I'm interested to know, how might the A330 compare in this occurrence?

There's some pretty deep water out there so I'm not so confident. Also, the wreckage could be scattered over a huge area if it did break up at altitude. It will also take several days for the search teams to reach the area.

Very distressing incident and one that I am sure will be hard to pin down the causes of any time soon.
As to the recovery of Data and Voice recorders and parts of airframe and engines then in addition to the oil industry vessels there are ships that maintain/repair undersea communications cables that carry the internet around the world.These vessels have remote controlled submersible vehicles and can lift modest weights from very great depths as the cables lie on the ocean floor. They are also pretty good at locating objects on the sea bed as the cables are only an inch or so thick but of course they would need a reasonable prediction of location so as to limit the searc area to practical dimensions. Unfortuneately even if there is aposition report in the last ACARS message if thatwas sent at cruising level then the radius of probaility as to where the aircraft hit the water is pretty large and compounded by currents and water densities which mean that something entering the seas surface does not sink verticaly downwards very often so it will be a real challnge to locate any wreckage but not impossible.

Location and salvage/recovery will be a very expensive and time consuming exercise but I would hope and indeed expect that it will be seen as a critical activity in order to avoid future incidents, maintain confidence in what seems a very sound design as well as to learn as much as possible from whatever specific causal factors are associated with this accident

it doesnt.

ELT
 

It seems odd that no ELT transmission has been received from the missing jet. Unless of course it's at the bottom of the ocean.

Surely some control surfaces are locked out during the cruise to prevent excessive movement at high speed?

The Air France statement about a lightning strike was at best speculation only. Poorly formulated and very misleading speculation.

The facts are that the aircraft's automatic ACARS (Aircraft Communication Addressing and Reporting System) simply sent out a random message giving some basic information on the status of some of the systems on board. It does this automatically.

Supposedly the electrical system and pressurization systems were suspect due to the ACARS message received. The fact that some "spokesman" is saying it was lightning based on this tiny shred of information leads me to discount any information given thus far.

Until we get more definitive information, that ACARS message could mean almost anything.

The Americans were lifting Russian submarines from the Atlantic in 1974.
Glomar Explorer

Recovery efforts began on June 20, 1974. The 63,000-ton Glomar Explorer located the wreckage on the seabed at a depth of 17,000 feet (5,200 m).

It may take a lot of time but it will happen.

Atlantic radar coverage (in reply to post#9, stallpusher)
 

I have wondered this sort of thing myself. Perhaps I shall do some investigation and start a new thread on the tech forum. One would think with some of the newer technologies (spy sats, weather sats, ocean ship radar data, etc.) and information processing technologies available some data could be extracted, albeit perhaps retrospectively. :hmm:

SA295 went down off Mauritius in 1987 in waters up to 5,000m deep. There was a catastrophic fire on board resulting in severe break-up of the wreckage. Still, they managed to find the cockpit voice recorder. I suspect in this day and age they'll have no problem finding the recorders.