Expanding a bit:
Bombs were classified by their CWR (Charge-to-Weigh-Ratio) the percentage of explosive compared to the gross weight of the weapon. GP (General Purpose) bombs had a CWR of 30-35% meaning that most of the weight of these bombs consisted of metal casing not explosive. When it was realized that the weight of the bomb casing is a necessary evil, something to be reduced as much as possible this led to the development of new weapons such as the 4,000 HC ('Block Buster') which greatly increased the offensive power of RAF's bombers.
MC (Medium Capacity) bombs had a CWR of 40-50% while HC (High Capacity) weapons had a CWR of 75-80%, the latter being essentially explosive packed metal drums. Extensive aerodynamic streamlining was dispensed with since these bombs were carried internally. As already mentioned the 4,000 lb 'Block Buster' or 'Cookie' was a very effective weapon in this class and after its introduction rapidly became a mainstay of Bomber Command.
Note: the were MC versions of both the 500 and 1000lb bomb.
SD = SPRENGBOMBE DICKWANDIG - Medium cased steel weapons and, being either anti-personnel or semi-armour piercing, had a charge-to-weight ratio of 35 per cent explosive; 50, 250, 500 and 1700 kg versions
However:
SC = SPRENGBOMBE CYLINDRICH - designed for maximum blast effect having a high charge-to-weight ratio of 55 per cent explosive SC bombs were used primarily for general demolition. Approximately 8 out of 10 of German high explosive bombs dropped on the U.K. were of the SC type. Sizes included 50 kg, 250 kg, 500 kg, 1000 kg "Hermann", and the 1800 kg "Satan". There was even a 2500 kg type although rarely used.
Maybe we've got the SD German bombs modelled? I dunno. Thoughts?
Gatso
