An air-filled or pneumatic tire consists of an inner core which is filled with pressurized air and sealed airtight. Normally, a tread made with reinforced steel belting or other kind of materials, provides the contact part with the road and seals this inner core.
The tire would remain inflated with all the vehicle's weight resting on it, as the pressure of the air inside the tire is greater than atmospheric air pressure. The pressure of the air in the tire gives resistance against forces which try to deform the tire. When the tire hits bumps in the road, this gives the tire a slight degree of a cushioning effect. If you have ever taken a ride in an old-fashioned carriage that had wooden wheels, you know how big of a difference a set of pneumatic tires makes.
Of course, there are some drawbacks to pneumatic tires. Like for instance in highly dangerous applications or high-performance situations, these tires can suffer a puncture and this will result in a complete failure. The consequence of a blowout at high speeds can result in a serious car accident. Military planners must consider tires getting blown out by firing of guns or explosion shrapnel. The worst nightmare of a vehicle crew is becoming trapped in a fire zone because of all of their tires becoming flat. Airless tires evidently don't suffer from these kind of issues and thus, in some applications, might be more suitable.
Pneumatic tires have another issue involving variations in air pressure and tire performance. 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. Therefore, less air pressure allows the tires' sidewalls to flex. This results in poor handling unfortunately. Within an airless tire, the stiffness in those two dimensions is independent.
There are other issues with air pressure. Customers are notoriously undependable when it comes to maintaining proper air pressure. Tires which have wrong air pressure could result in unsafe situations. It is very vital to keep in mind that pneumatic tires are also susceptible to temperature changes, that can be responsible for changing the internal pressure of the tire. It is important to take into account the kind of environments you will be requiring your machine to function in so that you can check the tires on a regular basis and keep the equipment as safe as possible.