According to the findings of a group tasked with investigating the mysterious disappearance of Malaysian s Flight MH370 in March 2014, the pilot flew the jet plane to an altitude of 40,000 ft, thereby depressurising the cabin's oxygen supply - killing the crew and all 238 passengers on board - before plunging into the depths of the Indian Ocean, where the Boeing 777 smashed in smithereens on impact.

https://www.thesun.co.uk/news/931896...-oxygen-crash/ ...

Why, indeed?

question remains unanswered.