The pilot flying, Bonin, had only 2,936 flight hours, of which only 807 hours were on the Airbus A330.
As soon as they got into trouble the more experienced left seat pilot (Robert, 6,547 flying hours, of which 4,479 hours were on the Airbus A330) should have said "MY plane!" and took over.
The icing event that caused the speed error/alternate law only lasted for just over a minute.
The issue was that he stalled it so slow (52k) the stall warning would stop, (all airspeed indications were now considered invalid by the aircraft's computer because of the high angle of attack) and as he pushed the nose down the speed would increase to where the alarm would start again and he would pull the nose up till it went off again. While that may have been confusing there is no stall recovery training that makes you pull up.
When the left seater figured out what was going on he put his side stick fwd but Bonin was still pulling up on his, so the inputs cancelled each other out. From there until the end of the flight, the angle of attack never dropped below 35°, so they fell from 38,000 ft and pancaked into the ocean.
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