On 17 Jan, 14:40, "Jack )"
wrote:
At 1250 (the accident was at 1242)

EGLL 171250Z 20013KT 9999 BKN008 10/08 Q0996 BECMG 24018G28KT SCT012
BKN020

so clearly the weather wasn't a factor.

Jack

On another thread, a knowledgeable jet pilot has surmised :

I suspect that the first point of investigation will be fuel waxing,
caused by exceptionally low temperatures en-route from China. The
temperature at FL380 was around -70C for much of the last two or three
hours of flight. The fuel regularly uploaded in China is Jet A1, which
has a freezing point of -47C. With skin heating, the Total Air
Temperature (TAT) (the ambient air temperature as modified by skin
heating) would have been around -50C. The B777 tanks are a little
better insulated than ours, but the fuel temperature would have been
below -40C, I suspect.

Whether this would cause a problem would depend on the rapidity of the
descent and how much opportunity the fuel had to warm up as the TAT
rose. The tendency to wax would also depend how much water was present
in the fuel (there's always some). Water drain checks would have been
carried out in Beijing, but it wouldn't be the first time they hadn't
been carried out correctly, or that insufficient water was drained.
The effect of fuel waxing is pretty instant when it happens: a friend
of mine lost all four engines on a Hercules from this, back in 1982.
Luckily for him, he was in the tropics and the fuel was able to heat
up sufficiently in the descent for a disaster to be averted - but not
by much. They decended from FL270 to 5000' in the process of
recovering the engines.

The point would obviously be raised, 'why did this not affect anyone
else?'. The answer may be one or more of many things, including
technical factors within the aircraft, as well as its individual
flight profile in the descent.

So perhaps the weather in a different place may have had an effect ??
What would usual temps at that flight level be ?
And what variation may be expected ?

Anyone know ?