Ken Rice wrote some very good words regarding problems when the body lacks
sufficient Oxygen.

In particular, you very quickly get stupid but don't realize it, and that
leads to
disaster.

Years ago I worked for Gen. Curt LeMay after he retired from the AF. He
liked to tell war stories at lunch and one in particular bears on the
subject.

In the thirty's, the US sent a flight of their latest bombers (B- something
or others - maybe B-13's) on a "Good Will" tour of South America and LeMay
was the group navigator. They went down the west coast of SA and had to
cross the Andes. The general said that in those days, little was known about
the effects of oxygen deprivation and the altitudes where it became a
problem.

During their crossing of the Andes, the whole group went up to about 13 -
15,000 ft. and flew there for a couple of hours before descending. As the
lead navigator, LeMay kept a detailed log of the trip, entering times,
leg-lengths, turn points, altitudes and any other observations or comments
that seemed pertinent.

When the flight returned to Washington at the conclusion of the tour, LeMay
reviewed his log-book to put the data into a formal report and came upon the
following notation (written while crossing the Andes): "Remember to pay my
dues to the Chesapeake Bay Rod and gun Club". What was interesting about
this entry was the fact that, as he relates it, "I didn't belong to the damn
Chesapeake Bay Rod and gun Club"!

Bottom line: Flying a while even in the mid-altitudes of 13 - 15K without
oxygen can make you get stupid and/or do something bizarre and you'll not
even recognize it's happening. The higher you go, the quicker it can happen
and the more profound the effects. A perfect recipe for disaster,
particularly when you need all your wits on tap.

Fly safe and keep your emergency oxygen supply handy!

Dan Schaefer