It’s hot. Africa hot. Shirt-soaked-in-sweat hot. And bumpy. Pothole bumpy. Two-fisted-shots-to-the-gut bumpy. I thought we had muscular summer thermals in South Florida, but these southern Texas bumps could teach ours a thing or two about how to throw punches.
We’re inbound to Austin-Bergstrom International, and these last few hot, bumpy, miserable miles are threatening to undo the excellent time we’ve had thus far. Four of us had left Fort Myers, Florida, early in the morning on a trip that would be a repeat of one I flew last year—up the west side of the Florida peninsula, turn the corner at Tallahassee, and fly west along the southern tier of the country to Texas. From there head northwesterly to Las Vegas, with a couple of off-course sightseeing vectors along the way.
The big difference between the two trips was the time of year. The first was flown at the official beginning of winter. This time we were heading out at the official beginning of summer. A very hot summer.
The news in Austin when we arrive in midafternoon is the heat—104 degrees Fahrenheit. Heat will be the constant for the next few days. Heat and height. Leaving Austin westbound, we rise with the land. After a bonus fuel stop in little Levelland, Texas, west of Lubbock—elevation 3,514 feet msl—we motor on to lunch at Sante Fe, New Mexico—6,348 feet msl—and then finish the day’s flying at 6,609-foot-high Grand Canyon Airport.
Leaving Florida we were within spitting distance of the Aztec’s 5,200-pound gross weight—four guys, six days worth of stuff, and full fuel. As we made our way west and it got hotter and higher, I kept reducing the takeoff weight the only way I could—by reducing the fuel upload.
Fuel strategy was a major issue on the trip. The goal at each stop was to strike a compromise between takeoff weight and endurance. On the one hand, I wanted the least amount of fuel possible to achieve the lowest possible takeoff weight and the best climb rate. On the other hand, I wanted as much fuel as possible to get where we were going plus have enough reserve to safely deviate around thunderstorms. Long legs were the norm from Austin westward because of the relative scarcity of airports with both avgas and a long runway.
It’s easy to plan long legs when the tanks are topped because you know exactly how much gas you start with. It’s a lot more difficult when you take on partial fuel because you’re not quite sure how much is in there. That’s why the Aztec’s J.P. Instruments FS-450 digital fuel computer proves to be one of the most valuable pieces of equipment on the panel. Along with accurately displaying fuel flow, fuel used, and fuel remaining, I could tell it exactly how much fuel we took on at each stop so I had an accurate reading of what was in the tanks when we taxied away from the ramp.
Leaving Sante Fe headed northwest, we had to jink around cumulonimbi gathering strength over the mountains. Coming into Grand Canyon Airport, the canyon itself was hidden by a wall of water cascading from a dark gray mass sitting directly overhead the deep gash in the Earth. We sat out the better part of an afternoon at a lonely airport in southeast New Mexico waiting for a surrounding army of storms to surrender. On the final leg home the entire midsection of Florida was girdled with angry weather. Negotiating all of that nastiness was made a lot less stressful thanks to the Aztec’s potent arsenal of Stormscope, airborne weather radar, and datalink Nexrad weather radar displayed on a Garmin 496.
We had fuel strategy and storm-avoidance covered. That left the heat. I don’t think there is anything that can drain a man of fluids, energy, and will faster than preparing an airplane for a flight when the ambient temperature is 90-plus degrees F and the humidity is even higher. Then, completely wilted, you get in the cabin, close the door, and try to get the big fans up front turning before everyone suffocates. At times like that I’d trade a type rating for some conditioned air.
That’s the only real complaint we have with the Aztec—lack of air conditioning.
A few laps around the EAA AirVenture exhibits last year turned up a couple of electric air conditioners under development, but we were hesitant about being an early adopter. The only solution appeared to be the Arctic Air, an Igloo cooler that has been modified with a bilge pump, heat exchanger, and a couple of electric fans. The idea is to stock the cooler with a shallow layer of water, then fill it with ice; block ice works best. The pump sucks water up from the bottom of the tank, circulates it through the heat exchanger, and then squirts it back over the ice where the bilge pump picks it up again in a continuous cycle. The fans pull ambient air through the heat exchanger and exhaust it out a couple of large ducts.
We put the cooler in the rear baggage compartment and, using a dryer-vent hose, connect it to a lightweight, hollow console we had made. The console has louvers to direct the cool air over hot bodies, just like a real air conditioner. Simple and cheap—about $600 for the dual-fan, 24-volt system needed for the Aztec—compared to traditional aircraft air conditioners, and surprisingly effective, too.
Thank goodness for that, because it’s hot. Austin-in-a-June-heat-wave hot.
Mark R. Twombly is the pilot on a Piper Aztec for a private owner. E-mail the author at [email protected].