The rebuilding of aircraft tires has been practiced for many years. A rebuilt tire is one that has a new

Figure 11-11.Sectional view of two aircraft tires showing different construction details.

tread section attached to a carcass or worn tire. Each rebuilt tire saves aircraft operators approximately 75 percent of the cost of a new tire. Data shows that a rebuilt tire gives service comparable to a new tire. The General Accounting Office (GAO) and the Department of Defense (DOD) policy mandates "aircraft tires will be rebuilt in all cases where economics can be realized without affecting safety of personnel and/or equipment." The Navy has established rebuilding criteria consistent with tire technology and service experience. By using this approach, functionally sound tire carcasses are returned to qualified contractors for rebuilding. In conjunction with these procedures, Navy laboratories monitor rebuilt tires to ensure the fleet receives a satisfactory product. The military rebuilt tire is as safe as, or safer than, a new tire because it is built on a service-tested tire carcass, whereas a new tire has had no service use to establish its construction reliability and performance suitability. Rebuilt tires are subjected to quality control procedures that are far more stringent than those imposed on a new tire. Unlike a new tire, each rebuilt tire receives a final nondestructive inspection with laser beam optical holographic methods. This procedure detects separa-tions, voids, and multiple cord fractures within the carcass, which are cause for tire rejection.

Figure 11-12 shows the points of measurement used to designate the size of a tire. For example, a tire with a size designation of 26 X 6.6 would have an outside diameter (measurement A) of 26 inches and a cross-sectional width (measurement B) of 6.6 inches. The letter X merely separates the two measurements. If the tires size designation were 26 X 6.6-10, then the tire would have a rim diameter (measurement C) of 10 inches. If only one numerical designation is used for a tire, you should assume that it is the outside diameter (measurement A).