Abstract: A method of fabricating a flexible fuel tank by firstly injecting an elastomer into a mold formed in the shape of a half-shell with a peripheral edge, cooling the peripheral edge of the injected elastomer, vulcanizing in-situ the entire half-shell except for the cooled peripheral edge, increasing the mold volume, halting the cooling of the peripheral edge, secondly injecting additional elastomer into the mold, and vulcanizing in situ the secondly injected elastomer, in addition to the peripheral edge of the firstly injected elastomer, such that the peripheral edges of the firstly and secondly injected elastomer half-shells unite, and the safety tank is formed of the thusly united half-shells.