Aircraft retreads... Michelin has a “cure” ! A worn car tyre, can be replaced; a worn aircraft tyre, however, is effectively renewed several times using the technique of retreading. The principle is simple; the outer portion of the worn tyre tread is removed and replaced by a new one... A worn car tyre can be replaced, a worn aircraft tyre, however, is effectively renewed several times using the technique of retreading. Experts in the subject are to be found at a Michelin plant in Bourges ( central France ).The principle is simple; the outer portion of the worn tyre tread is removed and replaced by a new one. "In fact we buff the tyre in order to remove the residual rubber and then we apply a new tread strip to the circumference of the tyre, using the same type of rubber as that on the original, giving us a new tread that we then cure in a press, after which the tyre is like new.” In using this method, 60-70 % of raw material in the spent tyre is saved. Regarding safety, nothing is left to chance. A tyre that requires retreading is subjected to a strict and lengthy process, including being tested and verified to see if the carcass, that is to say the basic part of the tyre, is not damaged too much, because if this is the case, retreading is not possible. In the best cases however, this can be redone up to six or seven times. Regarding price, it’s hard to say, because airlines do not buy retreads directly. "In marketing terms, we do not sell a retread, in fact we sell new tyres together with a certain number of landings, and therefore the cost of the landings will include a number of retreads and so being able to retread tyres, such as for a conventional A-320 for example, takes us from 600 landings, up to several thousand thanks to retreading.” Airlines have a sort of “all encompassing contract” with the tyre manufacturer. This contract will include : new tyres, retreading, and guarantee a certain number of landings - a sort of “all inclusive" package; however the cost of this "package" is difficult to ascertain; in fact manufacturers are not very talkative about the subject. One last detail, the retreading technique concerns tyres for commercial aircraft with a diameter greater than 15 inches because this industrial process requires expensive specific investments, therefore, retreading smaller tyres, like those for small ‘planes for example, would not be cost effective.