A pneumatic or air-filled tire consists of an inner core that is filled with pressurized air and sealed airtight. Typically, a reinforced steel belted tread or other type of 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 pressure of the air inside 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 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 makes.
Of course, there are some drawbacks to pneumatic tires. Like for example in highly dangerous applications or high-performance situations, these tires can suffer a puncture and this will lead to a total failure. The consequence of a blowout at high speeds could lead to a serious car crash. Military planners should take into consideration tires getting blown out by shooting 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 issues and therefore, in certain applications, might be more suitable.
Pneumatic tires have one more problem involving variations in air pressure and tire performance. 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 pressure of the air in the tire works to maintain the lateral stiffness of the tire as well as maintain the "up and down" stiffness. Therefore, less air pressure enables the sidewalls of the tires 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. Consumers are notoriously undependable when it comes to maintaining proper air pressure. Tires which have incorrect air pressure could lead to dangerous situations. It is really vital to note that pneumatic tires are also susceptible to temperature changes, that could be responsible for changing the internal tire pressure. It is really essential to take into consideration the type of environments you will be requiring your equipment to operate in so that you can frequently check the tires and keep the equipment as safe as possible.