The cloud were building beautifully over the California coast range. I was back from college for the weekend and itching to fly, so I grabbed my camera and hopped into one of the Fresno Sky Riders Club Cessna 150s. It was a 1963 model with the standard Continental O-200 engine, producing 100 galloping horsepower — no modifications, full fuel, calm day over the San Joaquin Valley with no updrafts. The fun weather was 60 miles to the west over the mountains. I was a skinny college kid, and 62Z took off smartly.
At the time, another young club member and I had a running competition (though not terribly serious) over who could take a 150 higher. The record was mine at that time — about 12,000 feet — because my friend was a little girthier than I. But an altitude record was not on my mind this beautiful fall 1971 day. I figured the cumulus would top out at about 8,000 or 10,000 feet, and my photo flight would be over.
Half a roll of Kodachrome slides later, the little airplane and I were at 12,000 feet, and both the clouds and Cessna’s finest trainer were still climbing nicely. I wondered if we could make it another thousand or two feet higher and seal the deal for the club altitude record. I kept climbing. By 14,000 feet I started to wonder how much higher the little airplane could go. I kept climbing: 16,000 feet, still climbing, 17,000 feet, still climbing and eking out a little more than 100 feet per minute.
At 18,000 feet, I took out my camera and set up for a shot of the panel to prove I actually made it to this altitude. I knew no one would believe me otherwise. Still ascending at 100 fpm, I steadied the camera and snapped off a shot with the altimeter now showing 18,300 feet. I was euphoric.
As I set the camera down and looked out the windscreen, I noticed something I had never seen before from the vantage point of my airplane — a Hughes Airwest DC-9 in its banana-yellow livery cruising straight and level only a few thousand feet above. I can only imagine the conversation between the captain and the first officer, if they even saw the little speck of blue-and-white Cessna below them.
The sight of that airliner nudged enough rational thought back into my brain to make me decide that mixing it up with airliners was not a wise idea, and I set up a gentle descent for Chandler Field. Not, however, before pulling out the chart to write down the date, time and location where this record flight took place. I was a history major, and this flight needed to be commemorated.
There were two problems with this. First, I could not figure out where I was. The world looks a lot different at 18,000 feet than it does at a few thousand feet, and this was long before GPS took the sport out of figuring out where you are. But with an educated situational guess, I picked up my pen, which brings me to the second and bigger problem. I could not make the pen do what I wanted it to.
Hypoxia! For the first time it dawned on me that I was experiencing a lack of oxygen due to the thin air at this altitude. My poor judgment (or, more accurately, the utter lack of it) that was evident in my continuing to climb into the high teens without oxygen, the euphoria, the inability to write — it all made sense now.
I had to get down to an oxygen-rich environment, and I had to get down now. I dropped the nose to begin a descent — not fast enough. I dropped the nose a little more but kept some power to avoid shock-cooling the engine — still not fast enough. I dropped the nose a little more, speed now increasing through the yellow caution band — still dead calm over the big San Joaquin Valley and now just brushing up against the 162 mph redline. And I was still not descending fast enough. I'd better do the opposite: slow it down, ease off power, full barn door flaps down. There we go: altimeter unwinding faster, now we are at 5,000 feet and all is well. Wait! That's 15,000 feet, not 5,000 feet!
It seemed like forever, but I finally got down low enough to get some oxygen into the carburetor and my lungs. I landed, and as I got out I found my legs were shaky from the hypoxia.
Although it may seem hard to believe, I was not a big risk-taker back then. I was all about safety when it came to flying. I went to every FAA pilot safety seminar I could find, aced the written exam and read every flying magazine I could afford to buy.
So how did I end up going way beyond a safe altitude when it was something I never would have planned to do on the ground?
Hypoxia is insidious. By the time I was moving through 12,000 to 15,000 feet, it had already begun to take hold, altering my judgment and making me careless about the risks of flying that high. When I was ascending above 15,000 feet, I was not even thinking about the need for supplemental oxygen. All I was thinking about was how high this little thing could go.
The flight took place shortly before the FAA adopted an oxygen rule, so the only FAR I busted was the last 300 feet climbing into what was then referred to as Positive Control Airspace (now Class A). Up until I reached 18,000 feet, I was perfectly legal, albeit foolish.
Now the rules are clear, and they make sense. For the pilot, you need supplemental oxygen when you are between 12,500 and 14,000 feet for more than 30 minutes and above 14,000 feet at all times. Passengers must get oxygen at 15,000 feet. This is a good rule. It would have kept me from climbing through 14,000 feet, maybe even 12,500, since I had no oxygen supplies on board. And with oxygen in my veins at a lower altitude, I would never have intentionally violated an FAR.
Sometimes, we pilots have to climb to get over mountains or buildups or Class B airspace. If this happens to you, and you are into that 12,500- to 14,000-foot gray area without oxygen, remember my flight to 18,000 feet before you stay there very long. For older pilots, smokers or people with poorer circulation, even 25 or 30 minutes may be too long. Stay below 12,500 and survive.
A few weeks after the flight, my photos came back from the drugstore. I looked carefully at the photo of the panel. It clearly showed 18,300 feet on the altimeter, the normal climb speed still being maintained and the rate of climb still at 100 fpm. And there was something else I hadn’t noticed when I was up there. The photo showed my left hand on the control wheel — and my thumb, which was blue.
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