The air-filled or pneumatic tire is composed of a core filled with airtight sealed pressurized air. Normally, a tread made with reinforced steel belting or other materials, provides the contact part with the road and seals this inner core.
Because the pressure of the air within the tire is more than atmospheric air pressure, the tire remains inflated even with a vehicles' weight resting on it. The pressure of the air in the tire gives resistance against forces that try to deform the tire. This gives the tire a slight degree of a cushioning effect when the tire hits bumps in the road. If you have ever taken a ride in an old-fashioned carriage that had wooden wheels, you understand how big of a difference a set of pneumatic tires can make.
Pneumatic tires also come with disadvantages. Highly dangerous applications or high-performance situations for example, these tires could suffer a puncture and this will result in a total failure. The consequence of a blowout at high speeds could result in a serious car accident. Military planners should take into consideration tires getting blown out by gunfire or explosion shrapnel. A vehicle crew's worst nightmare is becoming trapped in a fire zone due to all of their tires becoming flat. Airless tires evidently don't suffer from these type of issues and thus, in certain applications, might be more suitable.
Pneumatic tires have one more problem involving variations in tire performance and air pressure. Lower tire pressure could create improved traction and increased comfort. This is due to the fact that tires flatten a little and more tread is touching the road. The air pressure in the tire works to maintain the "up and down" stiffness as well as maintain the lateral stiffness of the tire. Hence, less air pressure allows the sidewalls of the tires to flex. Unfortunately, this results in poor handling. In an airless tire, the stiffness in those two dimensions is independent.
There are other problems with air pressure. Consumers are notoriously unreliable when it comes to maintaining correct air pressure. Tires that have incorrect air pressure can result in unsafe situations. It is very important to keep in mind that pneumatic tires are prone to temperature changes too, that can be responsible for changing the internal pressure of the tire. It is important to take into consideration the kind of settings you will be needing your machinery to operate in so that you can check the tires on a regular basis and keep the machine as safe as possible.