The air-filled or pneumatic tire is composed of a core filled with airtight sealed pressurized air. Typically, a tread made with reinforced steel belting or other materials, seals this inner core and provides the contact area with the road.
As the pressure of the air in 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 provides resistance against forces that try 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 ever taken a ride in an old-fashioned carriage that had wooden wheels, you know how huge 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 can suffer a puncture and this will lead to a complete 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 explosion shrapnel or firing of guns. The worst nightmare of a vehicle crew 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 certain applications, may 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 because of the fact that tires flatten slightly and more tread is touching 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, less air pressure allows the tires' sidewalls to flex. This results in poor handling unfortunately. In an airless tire, the stiffness in those two dimensions is independent.
There are other problems with air pressure. Customers are notoriously undependable when it comes to maintaining proper air pressure. Tires that have wrong air pressure could result in unsafe situations. It is essential to keep in mind that pneumatic tires are also prone to temperature changes, which could be responsible for changing the internal pressure of the tire. It is vital to consider the kind of environments you would be needing your equipment to function in so that you could regularly inspect the tires and keep the machinery as safe as possible.