While number four for takeoff on a 95-degree day, windows and doors open to catch any puff of moving air, every pilot ever minted has wished for air conditioning. With installed units starting at over $4500 and eating up at least 50 pounds of useful load, most owners are willing to sweat a bit and then climb to cooler air.
There is a much lower price alternative—portable aircraft coolers made from modern ice chests/coolers that use a fan to blow air across a heat exchanger full of cold water from ice (never, ever dry ice) to circulate cool air through the cabin.
At prices from $299 to $650, and weights of 30 to 63 pounds when loaded with ice, we wondered whether portable aircraft coolers are a viable option to installed air conditioning.
After using three of the most popular on hot days, we think that if an owner has reasonable expectations all of the units do a good job of cooling—after all, one pound of ice provides only 144 BTUs of cooling versus the 5000 to 10,000 BTUs from installed air conditioners.
The Review
The coolers were placed in the baggage compartment (except for the Arctic Air—the power cord was too short) of our test airplane, a Cessna T210, and flown out of Denver’s Centennial Airport. In each test the airplane was parked in the sun until the cabin exceeded 95 degrees F. Each unit was not turned on until the aircraft engine was started—the units plug into the cigarette lighter.
Our conclusion is that realistic use of a portable cooler is for taxi, takeoff and climbout to more moderate temperatures at altitude. It is then shut off. On descent, the cooler is turned back on and will keep the interior cool through landing and taxi in. Realistic cooling time is on the order of two to three hours—plenty for most flights. All of the units require some water to be added with the ice when the cooler is filled. Each uses a marine bilge pump—which must be mostly submerged—to pump the cold water through a heat exchanger and back into the cooler. A fan pulls in cabin air, blows it across the heat exchanger and the ice and exhausts it through louvers or a duct, into the cabin.