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The tires on airplane wheels seem to be a lot thicker than automobile tires. Next to that many airplane tires also seem to have much less tread pattern compared to car tires.

Why do the wheels on modern airplanes look so different to car wheels and why? When the airplane was first invented the wheels on it looked very similar to those of a car. But now-a-days airplane tires have a completely different design.

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    $\begingroup$ There is a very wide range of types of airplane wheels! (And even wider if we say aircraft!) $\endgroup$ Feb 1 at 1:58
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    $\begingroup$ I have a vague recollection that aircraft tyres are often still crossply designs, rather than steel-belted radials as a modern car would have, but can't find anything either way. Remember the tyres aren't in use for most of a flight, so the wear is from two runway taxis, a landing and a takeoff. The total mileage travelled is irrelevant :) Commenting cos no evidence. Related aviation.stackexchange.com/questions/73668 $\endgroup$
    – Criggie
    Feb 1 at 21:39
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    $\begingroup$ Aviation people are all "FAA this, FAA that"... they have no appreciation for how a fine set of rims will make your ride look nicer. And handle better in turns with low-profile tires! $\endgroup$ Feb 2 at 19:35
  • $\begingroup$ You'll like this: youtube.com/watch?v=RhwDlFamB20 $\endgroup$ Feb 2 at 21:30

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Let's start with tire pressure. A car tire has somewhere between 2 and 3.5 bars (that's 29 to 51 psi) while airplane tires go up to 24 bars (350 psi). Next, they must withstand extremely heavy loads for a short time. The spinup and impact load of a standard airliner landing would let any car tire burst in the same circumstances.

In order to be retractable, and even more when not retractable, airplane tires must be as small as possible. An extreme example is the Tu-144, where each main gear had 8 wheels to keep individual tire size down.

The tread on an aircraft tire does not have to transmit torque continuously, only during spinup and when braking. It must give good directional stability in crosswind and avoid hydroplaning as much as possible. This is best achieved with circumferential grooves.

The number of plies of an aircraft tire are more numerous and the rubber thickness is much higher than those of a car tire, proportional to the tire pressure and the spinup and braking loads.

An important addition comes from JohnK: An important design factor unique to aircraft wheels, even GA wheels, is that the tire must be unable to come off the rim under extreme lateral load with underinflation, which means much more rim/bead overlap, which in turn means the tire can't be stretched over the rim to install it, and the rim is instead made in two halves bolted together.

The tires also need to be able to withstand far more heat than a normal car tire. One of the requirements for a jet aircraft to be certified by the FAA is that a plane with minimum specification brakes must be able to fully reject a takeoff using only the brakes. The plane must then still be able to taxi for five minutes (worst-case assumption for an airport with no on-premises fire/rescue), which means the tires need to be able to withstand that extreme environment for a short time.

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    $\begingroup$ Another important design factor unique to aircraft wheels, even GA wheels, is the tire must be unable to come off the rim under extreme lateral load with underinflation, which means much more rim/bead overlap, which means the tire can't be stretched over the rim to install it, and the rim is instead made in two halves bolted together. $\endgroup$
    – John K
    Jan 31 at 19:52
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    $\begingroup$ @JohnK Right, thanks! If you don't mind, I add this to the answer $\endgroup$ Jan 31 at 21:45
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    $\begingroup$ In addition, because of the thick structure of an airplane tire, its rate of flexural heating will be much greater than for example that of a car tire especially if it is underinflated. This means if you try driving an airplane tire around all day on the freeway, it will get hot enough to self-destruct- which it will not do on a takeoff or landing because the running time is much shorter in those cases. $\endgroup$ Jan 31 at 23:01
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    $\begingroup$ @James In your 4x4 you are right, but my front wheel drive has exactly the same free-spinning wheels on its rear wheel suspension. The front wheel suspension of the Piaggio Vespa was even inspired by airplane landing gears. $\endgroup$ Feb 1 at 14:17
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    $\begingroup$ @PeterKämpf: Good point about some car wheels not being drive wheels! Of course most car wheels are still bolted onto a flange regardless. Most aircraft wheels are not bolted on because they either have no braking (nose/tail wheels) or they interact directly with the brake through keys and slots. $\endgroup$
    – James
    Feb 1 at 14:58

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