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The "Tall Boy" and "Grand Slam" Bombs
"Tall Boy"
Type Deep Penetration Bomb
Length 6,35 meter (21 feet)
Diameter 0,95 meter (38 inches)
Weight 5.443 kg (12.000 lb)
Warhead 2.358 kg (5.200 lb) Torpex explosive *
Number used 854
These massive bombs designed by Dr. Barnes Wallis reached the speed of sound during descent being streamlined and equipped with angled fins that produced a rapid spin. Penetrating the ground before exploding they worked by setting off shock waves that would bring down nearby structures. The 5.443 kg (12.000 lb) "Tall Boy" dropped from 6.096m (20.000 feet) made a 24 meter (80 feet) deep crater 30 meter (100 feet) across and could go through 4,88 meter 16 feet of concrete. On 8-9 June, 1944 eight Lancaster bombers of No. 617 Squadron used the deep penetration "Tall Boy" bomb in an attack against the Saumur Rail Tunnel. The new weapon proved its worth, but at the cost of losing 5 of the 8 bombers on this mission. Eventually 854 Tallboy bombs were used, the most note-worthy mission resulting in the destruction of the battleship Tirpitz (77 were dropped in three attacks).
The "Tall Boy" bomb was the second biggest bomb used in WWII.
* "Torpex" means Torpedo Explosive. It was originally used for torpedoes and therefore got this name.
"Grand Slam"
Type Deep Penetration Bomb
Length 7,7 meter (26 feet 6 inches)
Diameter 1,17 meter (3 feet, 10 inches)
Tail Section length 4,11 meter (13 feet, 6 inches)
Weight 9.979 kg (22.000 lb)
Warhead 4.144 kg (9.135 lb) Torpex explosive *
Number used 41
The "Grand Slam" (Earthquake) bomb was of the same design as the Tallboy but larger and heavier weighing 9.979 kg (22.000 lb). The Grand Slam was first used on 14 March, 1945 when a force of Lancaster bombers led by Royal Air Force Squadron Leader C.C. Calder attacked the Bielefeld railway viaduct destroying two spans. In another attack against submarine pens, (Bunker Valentin) near Bremen, two Grand Slams pentrated 4,5 meters of reinforced concrete. 41 Grand Slam Bombs were dropped by the end of the war mainly against bridges and viaducts.
The "Grand Slam" bomb was the biggest bomb used in WWII at all.
* "Torpex" means Torpedo Explosive. It was originally used for torpedoes and therefore got this name.
http://www.bismarck-class.dk/tirpitz/mi ... llboy.htmlThe weight of the Tallboy and the high altitude required of the bombing aircraft meant that the Lancaster bombers used had to be specially adapted. Armour plating and even defensive armament were removed to reduce weight and the bomb-bay doors had to be adapted. Even then the Lancaster was not capable of reaching the bomb's intended dropping height of 40,000 ft (12,200 m) but only around 25,000 (7,700 m)
http://en.wikipedia.org/wiki/Tallboy_bombVariants
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B.I
The original Lancasters were produced with Rolls Royce Merlin XX engines. Minor details were changed throughout the production series - for example the pitot head design was changed from being on a long mast at the front of the nose to a short fairing mounted on the side of the fuselage under the cockpit. Later production Lancasters had Merlin 22s and later Merlin 24s. No designation change was made to denote this change.
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B.I Special
Adapted to take first the super-heavy Tallboy and then Grand Slam bombs. Uprated engines with broad bladed propellers gave more power; the removal of gun turrets reduced weight and gave smoother lines. For the Tallboy the bomb bay doors were bulged — for the Grand Slam they were removed completely and the area faired over.
http://en.wikipedia.org/wiki/Avro_Lancaster
http://www.kotfsc.com/aviation/lanc-v.h ... %20SpecialHope this helps.