A pneumatic or air-filled tire is composed on an inner core which is filled with pressurized air and sealed airtight. Normally, a tread made with reinforced steel belting or other materials, seals this inner core and provides the contact part with the road.
Since the pressure of the air inside the tire is greater than atmospheric air pressure, the tire remains inflated even with a vehicles' weight resting on it. The air pressure in the tire provides 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 experienced taking 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 several disadvantages to pneumatic tires. For instance in high-performance situations or highly dangerous applications, these tires could suffer a puncture and this would lead to a total failure. The consequence of a blowout at high speeds could result in a dangerous car crash. Military planners should consider tires getting blown out by explosion shrapnel or gunfire. A vehicle crew's worst nightmare is becoming trapped in a fire zone due to all of their tires becoming flat. Airless tires obviously don't suffer from these problems and hence, in some applications, may be more suitable.
Pneumatic tires have another issue involving variations in tire performance and air pressure. Lower tire pressure can create increased comfort and improved traction. This is due to the fact that tires flatten a little and more tread is touching the road. The air pressure inside of 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. Unfortunately, this leads to 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, consumers are notoriously undependable. Incorrect air pressure within tires can lead to really dangerous situations. It is really essential to bear in mind that pneumatic tires are susceptible to temperature changes too, that can be responsible for changing the internal tire pressure. It is really vital to consider the type of settings you will be needing your machine to operate in so that you can regularly inspect the tires and keep the machinery as safe as possible.