280-250 McCreary Tailwheel Inner Tube, Bent Valve

Distributed by Specialty Tire of America aircraft tailwheel tubes are made of butyl rubber and are made slightly undersize, so they fill fit easily into a new tire. Aircraft-tire plies are made of nylon, and tires will "grow" slightly, in service. The tube will also grow, and will eventually take a permanent set to the (now) larger inside-tire dimension.

If this now-larger tube is later put into a new tire, it may be too large for the inside-tire cavity, with the result that the tube may have folds in it. In service, these folds may eventually wear through and destroy the tube's ability to hold air.

A slow wearing through will result in a slow leakage of air, and the pilot will be alerted to the problem before it becomes too serious. However, if the tube is torn in a particular takeoff, the tire will probably go flat in mid-air, without the pilot having realized what is wrong. Considering the risks in reinstalling a used inner tube, it is recommended that a new tube be installed in a new tire.