The raid was on April 16 1945 against the "Pocket Battle Ship" Lutzow by the specialty Squadron 617. One Lancaster was lost on the operation and flak was very heavy. The Lutzow was "holed" by a near miss. 617 was known for their precision work with specialty bombs, including, the bomb that destroyed the Mohne Damn on May 23, 1943. Tallboy bombs were used on U-Boat Pens, and other reinforce concrete structures. It was the Tallboy that sank the Tirpitz. The Bielefied Viaduct was destroyed by the 22,000 lb Grandslam dropped by 617 Squadron on March 14, 1945, a larger version of the same design. The Grandslam remains the largest conventional bomb ever used. These weapons were dropped from 18-20,000' and they took advantage of the camouflet effect developed from an explosion deep in the ground. They basically shook land structures apart. They were very expensive bombs to make. The Wikipedia article is a reasonable source of information.
https://en.wikipedia.org/wiki/Tallboy_(bomb)
The MOAB bomb is very slightly smaller but carries more explosive material:
"During World War II, Royal Air Force Bomber Command used the Grand Slam, officially known as the "Bomb, Medium Capacity, 22,000 lb" 42 times. At 22,000 lb (10,000 kg) total weight, these earthquake bombs were technically larger than the MOAB. However, half their weight was due to the cast high tensile steel casing necessary for penetrating the ground - up to 40 m (130 ft) - before exploding. The MOAB, in contrast, has a light 2,900 lb (1,300 kg) aluminum casing surrounding 18,700 lb (8,500 kg) of explosive Composition H-6 material.[22]"
https://en.wikipedia.org/wiki/GBU-43/B_MOAB
This is some good video of the event:
https://www.nordkurier.de/ueckermue...zitterten-die-fensterscheiben-1341028510.html
Note that the bomb was not to be detonated. Apparently they were going to "burn" out the explosive somehow. I guess that didn't work very well.
My father flew Lancasters during the war however he never carried this ordinance and the maximum bomb load he carried was only 13,000 Lbs. A note of interest. Dad bombed the U-Boat Pens in Bergen Norway on October 4, 1944. His 1,000 lb Armour piercing bombs bounced off the3.5 metre roof. On January 12, 1945 Bomber Command returned with 617 and 9 Squadrons carrying tallboys. Three of these bombs pierced the roof and put the pens out of commission. The Pens survive to this day and are used by the Norwegian Navy as shelters.
