Hi ross_M,
Originally Posted by ross_M
Did the pitots stop working because of the snow or being away from envelope?
At first, because of ice crystals. This issue #1 lasted a bit less than 1 minute and it was cleared before they were actually stalled (but stall warnings were not affected by this fault).
Later in the sequence, alpha went so high (above 35°) that both pitot and alpha probes were out of boundaries (hence, Stall warnings stopped). issue #2 happened 40-50 seconds after the full stall developed.
The main confusion is due to #2 starting too closely after #1, the crew being not able to deal with any of them (neither UAS nor Stall).