Self-sealing fuel tank

A self-sealing fuel tank is a type of fuel tank, typically used in aircraft fuel tanks or fuel bladders, that prevents them from leaking fuel and igniting after being damaged.

Typical self-sealing tanks have layers of rubber and reinforcing fabric, one of vulcanized rubber and one of untreated natural rubber, which can absorb fuel when it comes into contact with it. When a fuel tank is punctured the fuel seeps into these layers, causing the untreated layer to swell, closing and thus sealing the puncture. A similar concept is also employed for making self-sealing run-flat tires.