He does reference the case of Helios Airways Flight 522[0], where a similar situation happened as a result of human error (leaving the pressurisation system set

He does reference the case of Helios Airways Flight 522[0], where a similar situation happened as a result of human error (leaving the pressurisation system set to manual). Plus, it's possible that the pilots had too much faith in the "9 sigma" system, hence misinterpreting the numerous warnings the aircraft gave them. Numbers prove us wrong every day.