"C J Campbell" wrote in message ...
I am thinking of getting a portable oxygen system to use on the 206 and
other aircraft that I fly. These hot summer days with high density altitudes
in Idaho and Wyoming leave me gasping. Maybe it is just age.

Pressure altitude is all that matters by the way. It's the partial pressure
of O2 that controls the diffusion.

Nelson seems to make nicely portable systems. My mechanic had me
pick her up a 6.3 cu ft. system for her RV-4. It's really light. Of course
a tank that small only lasts a few hours on a charge... They have larger
ones.