Q: Hi Steve,
I’m a 56-year-old man. I had a good job and retired a couple of years ago. I was approached by a fella at my local airport who wanted to sell me his Piper PA-22 Tri-Pacer.
I didn’t know much about Tri-Pacers so I asked my flight instructor what he thought, and I got a mechanic to check it out.
My instructor described the Tri-Pacer as a good, if somewhat unusual airplane. He said it performs as well as a Cessna 172 and sells for a lot less.
Well, I bought it and have been flying it around Oklahoma and Texas for the last six months.
Now I’m considering a flight from my home in Oklahoma to southern Oregon next month. I’ve been taking my PA-22 to a local airport on hot days (90 degrees F or hotter) with a real long runway and making takeoffs with 60 and 70 percent power to get a feel for the loss of performance I’ll experience when flying in the mountains. It’s pretty dramatic.
I’ve read lots of magazine articles with lists such as “Top 10 Mountain Flying Tips,” and “Density Altitude for Dummies,” so I have a pretty good idea about how altitude and temperature will affect my flight.
My plan is to fly early in the day and give myself plenty of time.
My question, though, is about oxygen. Do you think I should get a small portable oxygen setup?
A; Dear Tom,
The Tri-Pacer won’t quite provide the same performance (or carry as much, or go as far when the fuel tanks are full) as pre-1967 Cessna 172s, but it’s not far behind. But a PA-22 is much less expensive.
There’s no denying Tri-Pacers are quirky: manual flaps; smallish fuel capacity (36 gallons); typical Piper overhead trim handle; bungee-cushioned main landing gear; a brake handle that applies braking to both mains simultaneously; and last but not least, a master switch that’s located under the pilot’s seat.
In spite of these quirks, most Tri-Pacer owners smile smugly when they hear others bad-mouth their airplanes.
If you take what’s called the Southern Route from Oklahoma (El Paso, Tex.– Phoenix–Twentynine Palms, Calif.–Apple Valley, Calif.–Palmdale, Calif.) into the California Central Valley, you’ll never have to fly higher than 7,500 feet.
I recommend that most pilots keep a small oxygen setup in their airplane just to be on the safe side. This is especially true if you aren’t physically active or are over age 50.
It will never hurt to take a few hits of oxygen if you spend more than a couple of hours flying above 6,000 to 7000 feet MSL or if you are flying at night. The restorative effects of oxygen will amaze you.
It’s a rule of thumb that blood oxygen levels should be kept above 90 percent during day flights and above 95 percent during night flights.
The only way to measure your blood saturation levels is by using a pulse oximeter. All you do is stick the end of one finger in an oximeter, and in a few seconds the unit displays your percent of blood oxygen saturation and pulse rate. Good units are available at many pilot supply stores.
Piper Flyer Association supporter MH Oxygen Systems provides a wide range of supplemental oxygen systems. One of the simplest is its Co-pilot System. This $215 system consists of three non-refillable bottles full of oxygen, a mask and a regulator that is adjusted to deliver flow rates of 33 percent, 66 percent and 100 percent.
At first glance it’s hard to imagine that these small bottles (they are approximately the size of a can of shaving gel) are capable of providing much protection—especially after reading on the MH website that one bottle provides a 100 percent oxygen flow (two liters/minute at sea level) for only nine to 10 minutes.
However, according to MH most users choose to extend the useful oxygen delivery time by taking regular “hits” of oxygen. One example cited was taking three breaths during a 10-second period every 15 minutes at the 100 percent setting. (The regulator is turned off between hits.) At this rate, the bottle/mask combination will last 12 hours.
The advantages of the Co-pilot include portability, light weight and affordability. And once you have the system, replacement bottles only cost $25. The duration can be extended substantially by using a $29 Oxymizer nasal cannula instead of the mask. Another advantage is that the bottles never have to be re-tested in accordance with Department of Transportation (DOT) regulations.
Larger kits from MH Oxygen Systems can be categorized as constant flow or pulsed flow systems. All constant flow systems include a storage bottle in a wide range of capacities, a regulator with up to six stations, and an adjustable flow meter and a normal cannula for each station. Each system is housed in a tough carry bag that’s fitted with straps and buckles intended to secure it to the back of the copilot’s seat.
Portable pulsed demand systems use MH Electronic Delivery System (EDS) O2 D1 or O2 D2 modules to monitor the users’ breathing cycles to deliver oxygen at the most beneficial period in each inhalation cycle.
According to MH, this innovation increases available oxygen per fill by up to 30 percent over constant flow systems. This means that the bottle size and weight needed is much smaller than the bottles used with constant flow systems to deliver the same blood oxygen saturation levels.
To put this in some kind of perspective, an individual pilot tapping oxygen from an AL-113—the smallest bottle MH sells—would be get 1.6 hours of oxygen when using what MH calls its MH4 adjustable flow meter and a normal cannula. He would get 4.7 hours of oxygen when using a MH3 flowmeter and an Oxymizer cannula and 6.9 hours of oxygen when equipped with an EDS O2D1 and an Oxymizer cannula.
I think I would start with the purchase of a pulse oximeter. If your saturation level goes below 90 percent at 7,000 feet MSL, I’d get the supplemental oxygen system and equipment that best fits your needs.
Know your FAR/AIM and check with your mechanic before starting any work.
Steve Ells has been an A&P/IA for 43 years and is a commercial pilot with instrument and multi-engine ratings. Ells also loves utility and bush-style airplanes and operations. He’s a former tech rep and editor for Cessna Pilots Association and served as associate editor for AOPA Pilot until 2008. Ells is the owner of Ells Aviation (EllsAviation.com) and the proud owner of a 1960 Piper Comanche. He lives in Templeton, Calif. with his wife Audrey. Send questions and comments to .