Tallboy was an earthquake bomb developed by the British aeronautical engineer Barnes Wallis. At 5 long tons, it could only be carried by a modified model of the Avro Lancaster heavy bomber. It proved to be effective against large, fortified structures against which conventional bombing had proved ineffective.
About Tallboy (bomb) in brief
Tallboy was an earthquake bomb developed by the British aeronautical engineer Barnes Wallis and used by the Royal Air Force during the Second World War. At 5 long tons, it could only be carried by a modified model of the Avro Lancaster heavy bomber. It proved to be effective against large, fortified structures against which conventional bombing had proved ineffective. Accomplishments of the Tallboy included the 24 June 1944 Operation Crossbow attack on La Coupole and a Tallboy attack on the Saumur tunnel on 8–9 June 1944. The last of the Kriegsmarine’s Bismarck-class battleships, the Tirpitz, was sunk by an air attack using Tallboys in Operation Catechism. At least 2 Tallboys failed to explode, one during the second attack on SorpejŚcie, Poland in 1960. While being defused in 2020, a second Tallboy was found during repairs in late 1958 and a second was found in late 1960s when the reservoir was emptied in Świnowiec, Poland. It was later used in the Battle of the Bulge in 1991 and the Second Lebanon War in 1991. The Tallboy can be found in the National Museum of the British Air Force and the Museum of World War II, London, on display for the first time in more than 50 years.
It is also on display at the British Museum in London, where it is on display alongside other WW2 memorabilia, including the original Tallboy bomb casing and a replica of the German V-2 bomber. The bomb was designed to be dropped from an optimal altitude of 18,000 ft at a forward speed of 170 mph, hitting at 750 mph. It made a crater 80 ft deep and 100 ft across and could go through 16 ft of concrete. To guarantee reliability, three fuzes were fitted inside the rear of the bomb casing to delay its detonation by up to 30 seconds. For use on underground targets, the bomb was fitted with three separate inertia-set detonation triggers, which gave it sufficient time after a pre-set delay to penetrate the target. The bombs were cast in one piece of high-tensile steel that would enable it to survive the impact before detonation. To achieve the penetration required, Wallis designed the bomb to be very aerodynamically clean so that, when dropped from a great height, it would reach a much higher terminal velocity than traditional bomb designs.