<<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>>
          <<  Lancair Builders' Mail List  >>
          <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>>
>>
I have a VERY strong recommendation.

I have used the mountain high units extensively at altitude.  Frankly those
units will keep your SO2 up in the high 87-92 range, EVEN at 23000 to
25000'.  They have a feature where they will turn on automatically if the
local pressure drops below a preset altitude (say, 12,000').  

Thus, if the PIC wears that simple canula when up above 20,000',  and you
suddenly loose pressure,  you will never face a crisis, as the O2 will come
on automatically and keep your SO2 up in a range you can work with
indefinitely.  

THAT is what I would do, routinely, if it were my aircraft.

Regards,  George Braly


>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
LML website:   http://www.olsusa.com/mkaye/maillist.html
LML Builders' Bookstore:   http://www.buildersbooks.com/lancair

Please send your photos and drawings to marvkaye@olsusa.com.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>