Tokyo tanks were internally mounted self-sealing fuel tanks used in the Boeing B-17 Flying Fortress and Consolidated B-24 Liberator bombers during World War II. Although nicknamed "Tokyo" tanks to dramatically illustrate the significant range they added to the B-17 (approximately 40% greater with combat weights), it was also an exaggeration in that no B-17 ever had the range to bomb Japan from any base in World War II.