Why don't aircraft tires explode when landing?

Thanks to such extraordinary durable tires, each flight becomes safer.

One thing almost never seen when a plane landed, it was a tire explosion. Think about that. From time to time, the tires collided with the surface of the runway at speeds of more than 270km / h and had to bear the burden of a normal office building on it, but they still did. At all times.

Aircraft tires are indeed one of the great things when you think about it. A typical aircraft tire can withstand 38 tons of load. It can land on the ground 500 times before it needs to be reworked. An airplane tire can re-groove 7 times during its lifetime.

A Boeing 777 uses 14 aircraft tires, the Airbus A380 uses 22 tires, and the Antonov An-225 giant needs 32 tires. According to Lee Bartholomew, chief test engineer for Michelin flying tires, the key to their extraordinary durability is by maximizing air pressure.

Picture 1 of Why don't aircraft tires explode when landing?
The key to their extraordinary durability is by maximizing air pressure.

Rubber tires in aircraft tires are often inflated to 200 psi, nearly six times the pressure for a car tire, and the tires on an F-16 fighter even get pumped up to 320 psi."The air pressure in it is really strong." He said.

The tires themselves are not too big - a Boeing 737 rolls on rubber tires 27x7.75 R15. This means that the tires are about 68.58cm in diameter, about 19.68cm wide and cover a 38.1cm diameter wheel. The tires of the tire are not too thick, but Mr. Bartholomew said, the tire's strength lies primarily in the fiber layer, which is placed beneath the tire groove.

They are usually made of nylon fibers, and more recently from a synthetic substance called aramid. Each crust contributes in part to the load capacity and the ability to withstand high air pressure in the tire. Of course, this tire can also explode, especially when it is too young or too much pumped. The groove of the tire may break and the outer shell may explode.

In the first moments after the plane hit the runway, the tires would slip and not roll. The plane essentially drags them on the surface of the runway until their rotation speed is equal to the speed of the aircraft.

That's why, they often smoke every time they land, and why Michelin uses even-straight grooves instead of the usual cubic patterns on cars' rubber tires - cubes that will simply break out of such pressure. (Most wear and tear of tires comes at times when landing - when rubber contacts the runway). The most durable tires can withstand speeds up to more than 460km / h.

Picture 2 of Why don't aircraft tires explode when landing?
The strength of the tire lies mainly in the fiber layer, which is placed underneath the tire groove.

To develop a new tire, or test an improvement point, Michelin begins with computer simulation, followed by modeling. Then, they will check to see how the tire will be when they are overloaded or pushed up to the limit on the simulation models when taking off, landing and running normally on the ground. Like everything in the aviation industry, aircraft tires must meet specific requirements and requirements, for example, an aircraft tire must withstand four times the rated pressure for at least 3 seconds.

"A tire is almost impossible to explode because the pump is too tight . " Mr. Bartholomew said. "In fact, in many cases when the tires are too inflated, the wheel will fail before the tires."