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-   -   Air France A330-200 missing (https://www.pprune.org/rumours-news/375937-air-france-a330-200-missing.html)

pattern_is_full 1st Jun 2009 17:52

At this time of year it is easy to encounter thunderstorms that can only be "flown over" by a U-2 or SR-71. I doubt any current airliner can top a 60,000-ft (12 Km) CB. My wife was SLF on a flight Sat. that was "dodging" thunderstorms, not flying over them. And that was over dry land in daylight, not a big swath of solar-heated ocean in the black.

The ITCZ is the birthplace of Atlantic hurricanes. We Yanks tend to be aware of it, since we are at the receiving end of the output. It's a rough place, and this is the beginning of its most active season. It can form a "wall" of storms that would require a 400 NM (or more) diversion to go around.

I'd put money on a weather-induced in-flight breakup. But the exact sequence of events and contributing causes (WX radar failure? Airframe failure caused directly by extreme turbulence? Airframe failure due to overspeed caused by loss of control?...etc.) may never be clear.

Which doesn't rule out something different - that's just the way I'd bet now.

I'm not sanguine about finding the FDR in a random part of the Atlantic that may span 100 square miles of water 2 Km deep. But maybe someone will get lucky...

Quintilian 1st Jun 2009 17:54

Pattern_is_full: Not that it matters, but according to charts the tropopause kicked in at FL510 over the TS-area earlier today, so no CBs over FL510.

barrymung 1st Jun 2009 17:56

In reply to #183, yes, you would have thought that positional data would be transmitted under these sort of circumstances.

However, I'm not sure when the system was developed, maybe it was designed in pre GPS days?

As the system allegedly reported an electrical failure, it's entirely possible the part responsible for providing positional data had failed.

khorton 1st Jun 2009 17:58


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?
If all electrics are lost the pilot still has pitch trim for pitch control, and the rudder for lateral-directional control. The pitch trim wheel in the cockpit is connected by cables to the control of the hydraulically powered pitch trim actuator. The rudder system is conventional hydro-mechanical control, with cables going from the cockpit to the rudder actuators.

Airbus did an approach and landing using pitch trim and rudder control only on an A320 during flight testing as a company test, in very good weather conditions (this is mentioned in "Cowboys d'Airbus", Bernard Ziegler). But they are very careful not to claim that it would be practical to count on this being possible in service, in real world conditions.

But, even though pitch trim and rudder do provide very limited control without any electrical power, it could get ugly pretty quickly if you combined this with the turbulence from a CB.

Note: none of the above is intended as speculation about what occurred on this flight. It was simply intended to answer the question posed earlier.

Aerospace101 1st Jun 2009 17:59

Can PAX still use sat phones etc if fitted? during emergency / loss of press etc.

CDN_ATC 1st Jun 2009 17:59

It depends where they went down....

Here is the chart of the area with the known info at this time:

http://i74.photobucket.com/albums/i2...47Crash1-1.jpg

wilyflier 1st Jun 2009 18:00

tropopause
 
thpaulsen,
Doesnt a really big CB punch up through the tropopause? Tops above cruising height anyway

grimmrad 1st Jun 2009 18:00

ACARS messages
 
Can the ACARS message be triangulated for the approximate location? Other stations receiving it? Also, is there any possibility to include the current location with it (and should it maybe required to send exactly that information every 10 minutes or so to comapny for cases like these...?)

Disclaimer: Not working in avaition industry.

cws 1st Jun 2009 18:01

no ELT
 
for what its worth, I followed the AF Flight by 5hours from Brasil to Europe unaware of what happend, but did not hear any ELT on the whole flight on 121.5.

jotape 1st Jun 2009 18:02

Wake up and smell le cafe...

If you thought the full story concerning the tech reasons behind BA38 was a little bit managed: "still not too sure about how this whole fuel/pump/ice thing happens but hey let's not ground all the 777s because its way too much money to lose and in any case - thanks to the BA pilot skills - nobody died..." - then you ain't seen nothing yet !

There is a complete convergence of interests at AF and Airbus to make sure once the black box is discovered the full story is totally managed so that we don't even think that maybe the A330 family (and for that matter the A340 family with which it shares so much) should be grounded until the mystery is solved...
Remember its one big statist monopoly all-been-to-the-same-school group of people that run industry in France...

P.S. Not anti-French nor anti-AF nor anti-Airbus - just providing a reality check !

eagle21 1st Jun 2009 18:02

http://3.bp.*************/_Xnchn6B0Z...h-Atlantic.JPG

http://student.britannica.com/eb/image?id=6004

Is the aircraft went down shortly after sending the failure messges to the AF MCC, ( 50NM after TASIL) , then the FDR and CVR shouldn't be deeper than 4000 meters, with some luck not even more than 3000 meters.

B777FD 1st Jun 2009 18:03

FDR & CVR transmitter range.....
 
It has been mentioned in this thread that the CVR and FDR locator signal has a range of 2 miles. Just ran an online conversion, that's 10560 feet (for statute mile at least). Is it possible the ocean is deeper than this?

Maybe tough to find within 30 days. :(

barrymung 1st Jun 2009 18:05

Assuming that reports are true and there was also cabin depressurisation, it appears as though there was a fairly catastrophic structural failure of some sort.

The A330/A340 differs from a lot of other airliners in that it has a horizontal tail section made from carbon fibre. Other sections of wing etc are also made from CF These sections contains a rather sizeable fuel tank.

When a metal section of aeroplane is hit by lightning, generally the charge is dissipated throughout the whole fuselage and damage is minimised. Carbon fibre, however doesn't dissipate a charge in the same way. Lightning hitting a carbon fibre panel usually results in sparking within that body cavity..

Whilst aircraft manufacturers go to great lengths to minimise the effects of lightning striking carbon fibre panels it's possible that such a strike could thus cause sparking inside the fuel tanks.

On the B787 there is a "fuel tank inerting" system that fills the "air" space of the fuel tanks with nitrogen in order to minimise the risk of ignition.

Does anyone know if the A330/340 is fitted with a similar system?

alexmcfire 1st Jun 2009 18:07

Any tracking record for the ships in the area?

Re-Heat 1st Jun 2009 18:11

To point out some deep inaccuracies about the depth of the Atlantic - read Atlantic Ocean - Wikipedia, the free encyclopedia (always a good bulwark against BS).


The principal feature of the bathymetry (bottom topography) of the Atlantic Ocean is a submarine mountain range called the Mid-Atlantic Ridge. It extends from Iceland in the north to approximately 58 South latitude, reaching a maximum width of about 1,600 kilometres (1,000 mi). A great rift valley also extends along the ridge over most of its length. The depth of water over the ridge is less than 2,700 m (8,900 ft) in most places, and several mountain peaks rise above the water and form islands. The South Atlantic Ocean has an additional submarine ridge, the Walvis Ridge.

The Mid-Atlantic Ridge separates the Atlantic Ocean into two large troughs with depths averaging between 3,700 and 5,500 metres (12,000 and 18,000 ft). Transverse ridges running between the continents and the Mid-Atlantic Ridge divide the ocean floor into numerous basins. Some of the larger basins are the Blake, Guiana, North American, Cape Verde, and Canaries basins in the North Atlantic. The largest South Atlantic basins are the Angola, Cape, Argentina, and Brazil basins.

The deep ocean floor is thought to be fairly flat, although numerous seamounts and some guyots exist. Several deeps or trenches are also found on the ocean floor. The Puerto Rico Trench, in the North Atlantic, is the deepest at 8,605 meters (28,232 ft). The Laurentian Abyss is found off the eastern coast of Canada. In the South Atlantic, the South Sandwich Trench reaches a depth of 8,428 metres (27,651 ft). A third major trench, the Romanche Trench, is located near the equator and reaches a depth of about 7,454 metres (24,455 ft). The shelves along the margins of the continents constitute about 11% of the bottom topography. Several deep channels cut across the continental rise.

pax britanica 1st Jun 2009 18:14

Jotape , just to add to your Francophobia the French have one of the largest fleets of submarine cable repair ships in the world and these are the optimim vessels for black box recovery in a situation like this.

Yes France is a pretty 'integrated' country but no more so than the US when it comes to self interest and if we Brits had any interests left to manage after we bankrupted them or sold them to foreign entities we would behave in exactly the same way.
I think you will find coffee smells the same the world over

BigHitDH 1st Jun 2009 18:15

Trainee (non-commercial) pilot question. So, you get hit by lightning during the cruise, have some electical issues (maybe loss of HF coms) and pressureisation problems. Do you descend into CB's?

vapilot2004 1st Jun 2009 18:17

@ Grimmrad:

ACARS triangulation would be possible if receiving stations commonly used directional antennas. Unfortunately, they do not.

Sparelung 1st Jun 2009 18:18

BigHitDH

From a physiology point of view, with loss of cabin pressurisation, you don't really have a choice about descent. Supplementary oxygen only lasts for a short while.

22 Degree Halo 1st Jun 2009 18:21

Here is the ship tracker: Ship locations


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