Originally posted by JD-EE ...
(Re: Tim Vasquez's WX analysis) It'll be interesting to see if anybody sees anything more in it that would bear on this accident.
I haven't gone back and re-read it, but far as I remember he didn't see anything out of the normal in the data he had at hand. The OAT was forecast around -46°C, and the actual data will be available from the FDR, including a complete temperature sampling all the way from FL380 to FL0 provided the probes could keep up with the rate of change.
The following pilot comment is probably pertinent,
"... we’re in the cloud layer unfortunately we can’t climb much for the moment because the temperature is falling more slowly than forecast". I note from Tim Vasquez's profile chart that he has indicated the FL350 temp as -43°C.
The crew knowing the OAT was on the high side and they were level FL350 at 205 tonnes, had already formed the opinion that climbing to FL370 per the FP wasn't an option. So, why a few minutes later when the AP/ATHR disconnected did they engage in this "zoom" climb?
It would seem that they were in the anvil cloud out-flowing from the prime Cb's, and this cloud was carrying a lot of moisture just ready to turn into ice crystals as it struck the pitots etc.. Did they at any time get on a thermal elevator?? I don't think so ... the only elevators in use were the ones attached to the airframe.
For the record, Tim has stated that thermal updrafts can reach speeds of 4 ~ 5,000 ft/min, but as far as I am aware that didn't occur that night .. daytime, maybe.
There is much more to what happened than has been revealed, and I suspect the real meat will be in the detail.