Narrative:

I was conducting a flight training cross country flight from hln to bzn. Clouds were scattered at about 11000 ft MSL. I found a large hole in the clouds to climb through, VFR, and wanted to show student what it's like to be above clouds. While climbing, we experienced several updrafts and decided to climb as high as possible. At the time, I was consciously thinking we could not be above 12500 ft for more than 30 mins. However, the oxygen requirement above 14000 ft evaded my memory, most likely because I had never considered that we could get to such a ht in a piper tomahawk. At 14200 ft, I realized my mistake and immediately conducted a high rate of descent descending turn to an appropriate altitude for our flight back. I am sorry for this lapse of memory and am now much more aware of our altitude and the concerning oxygen requirements.

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Original NASA ASRS Text

Title: A PA38 CFI REALIZED THAT HE WAS VIOLATING THE OXYGEN REQUIREMENTS DURING A TRAINING FLT IN ZLC'S AIRSPACE.

Narrative: I WAS CONDUCTING A FLT TRAINING XCOUNTRY FLT FROM HLN TO BZN. CLOUDS WERE SCATTERED AT ABOUT 11000 FT MSL. I FOUND A LARGE HOLE IN THE CLOUDS TO CLB THROUGH, VFR, AND WANTED TO SHOW STUDENT WHAT IT'S LIKE TO BE ABOVE CLOUDS. WHILE CLBING, WE EXPERIENCED SEVERAL UPDRAFTS AND DECIDED TO CLB AS HIGH AS POSSIBLE. AT THE TIME, I WAS CONSCIOUSLY THINKING WE COULD NOT BE ABOVE 12500 FT FOR MORE THAN 30 MINS. HOWEVER, THE OXYGEN REQUIREMENT ABOVE 14000 FT EVADED MY MEMORY, MOST LIKELY BECAUSE I HAD NEVER CONSIDERED THAT WE COULD GET TO SUCH A HT IN A PIPER TOMAHAWK. AT 14200 FT, I REALIZED MY MISTAKE AND IMMEDIATELY CONDUCTED A HIGH RATE OF DSCNT DSNDING TURN TO AN APPROPRIATE ALT FOR OUR FLT BACK. I AM SORRY FOR THIS LAPSE OF MEMORY AND AM NOW MUCH MORE AWARE OF OUR ALT AND THE CONCERNING OXYGEN REQUIREMENTS.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.