by Dave Weiman
I have always followed the FAA requirement to use oxygen for any flight over 30 minutes at 12,500 feet MSL and above, but seldom go that high, so this has not been an issue. But what I did not realize is that oxygen depletion actually begins at 5,000 feet MSL.
For years, when my wife, Peggy, and I would take a cross-country flight, she would ask me not to go above 5,000 feet because she would feel light-headed and sometimes get a headache. I have tried to accommodate her as much as possible, but as most instrument-rated pilots know, one’s altitude depends on the weather, winds aloft, and cloud cover. So in the end, Peggy would usually give in and suffered the consequences, until a friend showed us his portable oxygen system. Our friend told us the same thing…above 5,000 feet MSL, he uses oxygen and feels great all day long.
“Hypoxia,” or oxygen deficiency, is a progressive condition, and is undetectable by pilots and their passengers, which makes it even more dangerous.
Without supplemental oxygen at a sufficient flow, occupants will gradually and progressively lapse into incompetence while maintaining an absolutely euphoric faith in their own ability. The less oxygen in one’s body, the greater the chance the pilot may make the wrong decision and could become unconscious.
While noticeable at 14,500 feet MSL due to the blood’s inability to carry oxygen, there is dramatic drop in oxygen saturation, which will be approximately 80% or fully hypoxic. A person left at this altitude may experience vertigo, nausea, weakness, increased breathing, decreased eye-hand coordination, slowed decision-making ability and compromised vision.
So come Oshkosh time, I went shopping and stopped by the “Precise Flight” booth where I met account executives Kenny Hill and Joe Wanko, and engineer Rob Norris.
Kenny, Joe and Rob demonstrated how their oxygen system works, and why people should have oxygen above 5,000 feet MSL, and while flying at night. They also knew their competition, and had a display of the “flow meters” for each manufacturer. The quality and ease of operation of the Precise Flight oxygen system made it clear as to whose equipment I wanted to buy.
Another great feature of the Precise Flight oxygen system is the “regulator.” You have your choice between a two-outlet and a four-outlet regulator. Since our Cessna 182 Skylane has four seats, I chose the four-outlet regulator, even though we seldom travel with four people. Also in the event an outlet would malfunction, we have two other outlets to use.
You have your choice of aluminum oxygen cylinders: 6.3, 15 and 22 cubic ft. capacity. Of course, the larger the cylinder, the more oxygen you have and the less likely you are going to run out on a long cross-country flight. Also when you go to refill the cylinder, there’s usually a flat rate, regardless of the size of the cylinder. On the other hand, the larger the cylinder, the more it weighs and it will consume more space inside your cabin. That’s where a built-in oxygen system which Precise Flight also manufactures, is nice, but it would not be practical for a 39-year-old airplane like ours.
We selected the 22 cubic ft. cylinder, which fits nicely behind the pilot or copilot seat, using Precise Flight’s well-constructed canvas case and harness system. The canvas case also has several compartments for storing the oxymizer cannulas or nose-only breathing devices, and face masks.
The way the system works is you set the flow meter to the altitude you expect to be flying at, and the regulator will automatically provide you with the amount of oxygen you need and no more. The only time you get oxygen is when you breathe in through your nose using the oxymizer nasal cannula, or through your mouth when using the face mask.
Another product offered by Precise Flight worth considering is “The Aviator’s Rescue Ruck,” which is a ready-to-go and lightweight aviation-specific emergency backpack, and bright red in color for easy recognition in an emergency. Included in the ruck is food, water, shelter, weather protection, first aid, cooking utensils, matches, communication devices and tools.
To learn about Precise Flight oxygen systems and other products, go to www.preciseflight.com or call 541-382-8684 and ask for Kenny, Joe or Rob.