Originally Posted by
what next
...
Many of these aircraft still carry an emergency oxygen bottle in the cabin though (intended to be used for passengers with health issues). If the pilot of this flight had an issue with his oxygen system he might have tried to get to that emergency bottle. That might explain why he could not be seen in the cockpit.
That is a very good point, that is. In our old 500, the theraputic oxy bottle was at the back of the cabin. 550s didn't have one.