The Fuel
With a fully open mind, the Fuel will attract attention, however.
Reading a release of information can be subject to premature conclusions, especially when very little further data is supplied. Nothing of what has been said by AAIB totally eliminates its consideration, obviously, since AAIB have Not provided a causal chain.
"Exceeding" the appropriate specification is a troubling statement. In what way? A Spec is a range of points that contain a compliant sample in all respects. Is a freezing point of -57 "better" than -49? Perhaps, but in what way; what about the Asian Fuel causes the odd (Though lower) temp? What about its composition makes it "different"?
BA038 flew at much higher altitude than other A/C in a similar profile. The 777 has but one Fuel Temp sensor, and it is located in the Port wing, which basked in the sun for much of the flight. Was 38C an accurate reading? Was the Sensor tested for performance? What of the Temp. elsewhere?
Was there some attribute of the Chinese Fuel related to its lower FP that ennabled it to contain water in solution as well as in emulsion?
In Soem Dood's defense (not that it is necessary), Fuel (Lack) is the proximate cause of loss of Thrust; Saying the Fuel played no part in a result that has remained publicly unexamined (completely) is very premature, very. Fuel temperature is a Fuel attribute. To be blunt, the Fuel on Board BA038 came from a supply that is not widely used in similar flights elsewhere, drawing attention simply by virtue of its "rarity".
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