An air-filled or pneumatic tire is composed on an inner core which is sealed airtight and filled with pressurized air. Typically, a reinforced steel belted tread or other type of materials, provides the contact part with the road and seals this inner core.
The tire would remain inflated with all the weight of the vehicle resting on it, since the pressure of the air within the tire is more than atmospheric air pressure. The air pressure in the tire provides resistance against forces which attempt to deform the tire. This gives the tire a slight degree of a cushioning effect as the tire hits bumps in the road. If you have experienced taking a ride in an old-fashioned carriage which had wooden wheels, you understand how big of a difference a set of pneumatic tires makes.
Of course, there are several disadvantages to pneumatic tires. Like for example in high-performance situations or highly dangerous applications, these tires can suffer a puncture and this would lead to a complete failure. The consequence of a blowout at high speeds could lead to a serious car accident. Military planners must consider tires getting blown out by firing of guns or explosion shrapnel. A vehicle crew's worst nightmare is becoming trapped in a fire zone because of all of their tires becoming flat. Airless tires obviously don't suffer from these problems and thus, in some applications, could be more suitable.
Pneumatic tires have one more issue involving variations in tire performance and air pressure. Lower tire pressure can create improved traction and increased comfort. This is due to the fact that tires flatten slightly and more tread is placed in contact with the road. The air pressure in the tire works to maintain the lateral stiffness of the tire as well as maintain the "up and down" stiffness. Thus, reduced air pressure enables 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.
Air pressure factors into other issues also. With regards to to maintaining correct air pressure, customers are notoriously undependable. Wrong air pressure inside tires could lead to really dangerous situations. It is essential to keep in mind that pneumatic tires are prone to temperature changes also, that could be responsible for changing the internal pressure of the tire. It is important to take into consideration the type of settings you would be needing your machine to function in so that you can inspect the tires on a regular basis and keep the equipment as safe as possible.