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Old 7th Jul 2009, 05:56
  #3160 (permalink)  
takata
 
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JD-EE:
At 420 knots the plane is going 7 miles a minute.
At 468 knots (Mach 0.82) and FL350, the plane is going 7.8 miles a minute, and this was F-GZCP configuration at 0210.

At 0210 we have a position. Presuming the plane was still aimed "roughly" along the planned flightpath and presuming perhaps some pushes by storm winds where could the plane have gotten to by 0214 plus maybe a little Kentucky Windage for surviving a bit past 0214?
Why would the plane be only "roughly" aimed along the planned flight path at 0210? By all calculations possible about her position, she was maybe slightly deviating 3 NM to the West, but not much. The "pushes from storm wind" is something you know for sure or is it your imagination?

This hard flying condition are not documented anywhere and all we can verify by sattelite IR imagery is that she was pretty close to the coldest part of the convective CB cells around her, but we are left without a single clue about how bad or good the real situation was. LH507 crossed 20 mn before with a 10 NM deviation West and reported only moderate turbulences. There is a strong evidence by F-GZCP thrust setting that she was not in severe turbulences at 0210. Please, give a little credit to the pilots and consider first that they will do what they were supposed to do, weather avoidance and turbulence procedures, until we got something like a hard proof that they failed to do so. The next Air France flight, 37 mn later, deviated 80 NM as it is not in the company policy to fly strait into bad weather for saving fuel. If they picked this way, it would have been painted safe (right or wrong) on their radar and they are supposed to have been trained well enough to use it, or we need evidence they were not.

"Where could the plane possibly be?" might be a better search criterion than "where do the currents extrapolate backwards to at the time of the crash?"
And, of course, I am fastened on to the apparent fact that the plane was either deceased or was no longer even approximately horizontal after 0214.
Again, it is mostly your imagination: what clue do we have for considering the aircraft 'deceased' at 0214? Unreliable air speed indications? Is it enough without adding a little bit more imagination: updraft, downdraft, storms, lightnings, stall, spin, spiral, dive, upsets, tailfin wiped out, computer glitches... crash?
All the facts we know for sure about the real weather situation is resumed in one word: ice. How we know it? The ACARS are telling us that the probes are freezing, that's all and we should stick with it as the primary weather issue encountered.

Aiming of the satellite antenna is somewhere between a TV yagi on a rotator and a pair of rabbit ears in a high signal area for reference. You can be a whole lot off and it still works. Plus or minus maybe 60 degrees of vertical for a 3dB (half power) loss. Within about 35 degrees you'd have trouble picking the optimum direction without automation.

This is why "what is the region it could have reached in 5 minutes or less is my search criterion. Then match that with the currents to try to refine it all. And I have an untutored hunch that turning an A330 or anything else at FL350 is not "sharp" by any stretch of the imagination unless you are purposely entering a dive as for a bombing run.
Then, all your 'search criterion' are mostly based on... imagination, but not on verified facts. Here is a relevant example where, if this incident would have ended in catastrophe a few miles before the runaway, without any communications and radar coverage, your imagination would have placed the crash site 85 nautical miles off the coast. This flight would have ceased to transmit any ACARS at 0626 @ FL345, after sending an engine failure at 0613 and when flying at FL390:

Air Transat Flight TS236, was en route at FL390 when at 05:36 UTC, the crew became aware of a fuel imbalance between the left and right-wing main fuel tanks. Five minutes later the crew concerned about the lower-that-expected fuel quantity indication, decided to divert to Lajes Airport in the Azores. At 05:48 UTC, when the crew ascertained that a fuel leak could be the reason for the possible fuel loss, an emergency was declared to Santa Maria Oceanic Control. At 06:13, at a calculated distance of 135 miles from Lajes, the right engine (Rolls-Royce Trent 772B) flamed out. At 06:26, when the aircraft was about 85 nm from Lajes and at an altitude of about FL345, the left engine flamed out. At 06:39 the aircraft was at 13,000 feet and 8 miles from the threshold of runway 33. An engines-out visual approach was carried out and the aircraft landed on runway 33. Eight of the plane's ten tyres burst during the landing.
Investigation has determined that a low-pressure fuel line on the right engine, had failed probably as the result of its coming into contact with an adjacent hydraulic line.

S~
Olivier

Last edited by takata; 7th Jul 2009 at 06:10.
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