Originally Posted by
givemewings
... it surprises me that a portable bottle isn't standard equipment for any pressurised aircraft with a stand up pax cabin (CC background here)
This series of Citations do not have a stand up pax cabin. Space inside the cabin is a little tight, especially when all seats are occupied. The usage of the portable therapeutic oxygen bottle is very difficult in such a confined space, especially for persons not properly trained for it (e.g. paramedics). The company I fly for had them removed many years ago.
Originally Posted by
B2N2
Anything else what the pilot may or may not have done is conjecture.
There are quite a few things that can be deducted from the state of the wreckage like: Was the pilot's seat belt buckled-up or open? Was his quick donning mask connected to the oxygen outlet? What was the setting of the pressurisation controls - they are mechanical in this aircraft, whatever values were set should still be visible. What position were the switches in that control the pressurisation system? There is a bleed-air selector, an automatic/manual switch and an emergency dump switch. Did the masks in the cabin drop?