Aircraft tires
When the rubber hits the runway
In 1904, his 20-winged monstrosity lifted (unstably) into the air, flew 50 feet, and returned to terra firma—on wheels. Hardly an impressive flight, but it set the stage for the bulk of all landings over the next century, minus those on water or snow.
The earliest airplane tires were solid rubber glued on spoked wheels, but it wasn’t long before the air-filled airplane tire was introduced, debuted by Traian Vuia in 1906. By 1909 Goodyear Tire and Rubber Co. was making pneumatic airplane-specific tires; and they are still in the business today. The other major players in the now $1.5-billion-a-year airplane tire market are Bridgestone, Dunlop, Michelin, and Specialty Tires of America.
That’s a lot of dough for rubber. Of course, a lot of it is spent in the commercial and military side. Tires for commercial jets can sell for as much as $5,500 each, and bear in mind that a commercial jet needs a lot more than the three tires most of us use. Cha-ching!
In general aviation, the cheapest tire is probably the tiny three-inch-diameter Azusa tailwheel tire. Topping the chart is the Goodyear Flight Radial for the Gulfstream G500 business jet at $3,512 a pop. Pardon the pun. Most GA tires run in the $100 to $300 range. Of course, that price doesn’t include inner tubes, which the lion’s share of general aviation tires still use. But airplane tires are increasingly tubeless. And, yes, it is legal to put a tube in a tubeless tire if you have the wrong kind of wheel. Meanwhile, as in the beginning, there are still solid rubber airplane tires—generally tailwheels where weight is less of an issue because of their small size.
Speaking of size, what’s the largest tire for the airplanes we fly? That would be the Bushwheel tundra tire, which has a 35-inch diameter.
Most airplane tires have a ribbed tread pattern for paved runways, but you can still get a diamond pattern for unpaved strips, a combo ribbed with diamond-edge for all weather, and classic smooth (think old Piper Cub). There’s also a special jet tire that has a funky ridge of rubber called a chine that deflects water on wet runways away from the engine intakes.
Why no spare
One of the items on the short list of maintenance that pilots can do on their own airplanes without the A&P certificate is changing a tire. But unlike cars, airplanes don’t generally come equipped with a spare in the trunk. Why not? While weight and space come to mind as limitations, that’s just the start of the trouble. On most GA airplanes, the main tires are a different size than the nose or the tailwheel tire. So, you’d need two spares. Plus, airplane wheels aren’t like car wheels with a few lug nuts holding them on. They’re a lot more complex, and getting one off usually includes brake disassembly. Plus, have you ever seen an airplane jack?
For, say, a high-wing? Think what that would do to your useful load! And let’s be honest, on properly maintained airplane tires, a flat is a rarity. Not to say it doesn’t happen, which could be why some pilots—especially those whose airplanes use unusually sized tires—do carry spare tubes, tires, or both, for faster field service if they have trouble away from home. Some flight schools (which go through a lot of tires) do the same. —WED
