further 25,000 were used. 8,000-lb HC Mk I Mk II Actual weight with charge to weight ratio of 68%. Filling was 'Amatex 9' or 'Torpex 2'. Bombs were produced from 1942 to 1945. 12,000-lb HC Mk I Mk II Charge weight ratio of 80%. Filling was Amatex or Torpex. 170 were produced in the last two years of the war. Other uses Air mines During The Blitz the Germans used naval mines dropped with parachutes as improvised blockbusters. Their fuse was triggered by the shock of landing, with the bomb exploding after a 17-second delay. As the bomb was not in a crater, the force of the blast would disperse laterally, causing extensive damage. The large raid on Coventry on 14–15 November 1940 included the use of 50 parachute naval mines, which caused extensive blast damage. The British called these devices air-mines, a calque of the German term Luftmine. These types were used also during air raids on Malta, especially on its harbour areas. See also Tallboy bomb Grand Slam bomb Firebombing Firestorm Pumpkin bomb, test Fat Man atom bomb casings filled with nearly of Composition B explosive SC 1800 Satan, the rough German equivalent of the American AN-M56 general purpose "blockbuster". BLU-82 MOAB References Citations Bibliography External links A 12,000lb HC blockbuster pictured in the factory minus-tail unit A 12,000lb HC blockbuster being dropped An 8,000lb HC blockbuster about to be loaded aboard a Lancaster World War II aerial bombs of the United Kingdom Weapons and ammunition introduced in 1941