I’m guessing no one has given any thought whatsoever about the tires that go on airplanes. And really, why should we? They’re only needed for about 2 minutes out of every flight right?
But think about the tremendous pressure those tires are under, especially when landing. It’s quite amazing to think you simply don’t hear about any tire issues on planes. Whether you’re talking about a flat tire, tire blowing out, or any other issues. It’s also crazy to consider the drastic temperatures the tires see too! Think about flying in the summer. Take off with an air temperature of 90 degrees with the tarmac well over 100. Then a few minutes later, the air temp may be below zero for a few hours. Then smacking down onto hot tarmac again. Quite an engineering feat to be sure. If one of these were to blow out, this isn’t your average semi tire repair job!
So, I was curious and did some reading.
I never thought about it this way, but an aircraft tire is a high performance tire. So like, Ferrari, Aston Martin, Lamborghini tires? Nope…. Way more high performance!
Typical passenger tires are pressurized to between 30 and 50 psig. The aircraft tire is inflated to about 200 psig. A fighter jet? 300 psig. The space shuttle (when they were flying)? 600 psig!!! It’s nearly impossible to over inflate aircraft tires, and it’s precisely that high degree of tire pressure that makes the tires themselves so strong.
Another element that makes these tires so much different than the tires we’re used to is the material they’re made out of. Our tires can expand as much as 10% depending on the temperature and speed. This is a lot and causes a lot of residual stress, but passenger tires can handle it as their internal pressures are low. Now, aircraft tires only expand between 1 and 2 percent. Consider why this is important, especially as it relates to air pressure (and the importance of air pressure in aircraft tires). If you fill a tire to 200 psig and that vessel expands 10%, the pressure in that vessel will reduce because that air must fill 10% more space…. Thus reducing the air pressure.
If there’s one thing I’ve learned, the more air pressure the better when it comes to airplane tires!
Ever thought about why the tires have straight grooves in them instead of the block designs of typical passenger tires? If you think about the first few seconds after a plane lands, the tires aren’t spinning. They basically skid until they’re able to catch up to the speed the aircraft is traveling. That skidding would rip those blocks right off the tire. It is that reason alone why you see the straight line patterns on the airplane tires and not the typical patterns on passenger tires.
Pretty cool eh?