[justlurking]

As a resident of Colorado, I can tell you that a LOT of low landers (anything below 2,000 ft) come out here and get disoriented at 9,000 to 10,000 ft.

As a "low lander" that has never smoked, I've noticed minor hypoxia effects after an extended time at 11,000 feet. I immediately asked for a lower altitude and have never been above 10,000 feet (aircraft cabin altitude) since then.

I've made trips to 14,000 feet (on Pike's Peak), but never stayed long enough to feel any effects.

[PilotDave]

“I’ve noticed minor hypoxia effects after an extended time at 11,000 feet. I immediately asked for a lower altitude and have never been above 10,000 feet (aircraft cabin altitude) since then.”
Umm- the difference in atmospheric ox levels between 10,000 and 11,000 is barely measurable, let alone detectable by the human body. Further, if you were fine at 14,000 ft on pikes peak, I’d surmise the symptoms you experienced in the plane were not hypoxia at all. More likely you are either afraid of flying or heights! What exactly were your symptoma anyway?