The SD 250 (Sprengbombe Dickwandig 250) or ''thick walled explosive bomb'' in English was a

fragmentation bomb Fragmentation is the process by which the casing, shot, or other components of an anti-personnel weapon, bomb, barrel bomb, land mine, IED, artillery, mortar, tank gun, or autocannon shell, rocket, missile, grenade, etc. are dispersed and ...

used by the

Luftwaffe The ''Luftwaffe'' () was the aerial-warfare branch of the German ''Wehrmacht'' before and during World War II. Germany's military air arms during World War I, the ''Luftstreitkräfte'' of the Imperial Army and the '' Marine-Fliegerabtei ...

during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

History

The second most used category of bombs was the SD series which were high-explosive bombs but with thicker casings which meant their charge to weight ratio was only 30 to 40% of their total weight. At first glance, they were difficult to distinguish from the SC series of bombs, but the two series were color-coded the SC series having yellow tail stripes, while the SD series had red tail stripes. Bombs in this series were the SD 1, SD 1 FRZ, SD 2, SD 10 A, SD 10 FRZ, SD 10 C, SD 15, SD 50, SD 70, SD 250, SD 500, SD 1400, and SD 1700. The number in the bombs designation corresponded to the approximate weight of the bomb. The SD series was used primarily in two roles that were determined by the type of fuze and accessories fitted to the bomb. The first was as a fragmentation bomb with instantaneous fuze and when the bombs exploded above ground the case created large fragments which would kill enemy personnel and destroy unarmored vehicles. The second role was as a general-purpose or

armor-piercing Armour-piercing ammunition (AP) is a type of projectile designed to penetrate either body armour or vehicle armour. From the 1860s to 1950s, a major application of armour-piercing projectiles was to defeat the thick armour carried on many wars ...

role. In this role, the bombs were fitted with a time delay fuze which detonated the bomb after it had pierced a target destroying it with a combination of its blast and fragments.

Design

The body of the SD 250 was of three-piece welded construction with a nose piece, center section, and tail sections. The tail cone was of sheet steel construction with four braced tail fins. The SD 250 had a transverse fuze pocket in the nose section, a dummy fuze pocket near the tail, and there was a central exploder tube which ran through 2/3 of the Amatol or

TNT Trinitrotoluene (), more commonly known as TNT, more specifically 2,4,6-trinitrotoluene, and by its preferred IUPAC name 2-methyl-1,3,5-trinitrobenzene, is a chemical compound with the formula C6H2(NO2)3CH3. TNT is occasionally used as a reagen ...

filling. The SD 250 was filled through the base and was fitted with a welded sheet steel tail cone with ribbed tail fins. A ''dinort rod'' could be added to obtain pre-penetration detonation for anti-personnel use. The SD 250 could also be fitted with a ''Hohlladung''

shaped charge A shaped charge is an explosive charge shaped to form an explosively formed penetrator (EFP) to focus the effect of the explosive's energy. Different types of shaped charges are used for various purposes such as cutting and forming metal, ini ...

that could be added to the nose of the bomb to increase its armor piercing capabilities. This attachment weighed and was detonated by its own nose fuze. To prevent damage to the bomb a cap made from cement and sawdust separated the explosive charge from the nose of the bomb. When fitted with this attachment the bomb used a delay fuze to explode the bomb after it had penetrated the target. The SD 250 could be vertically or horizontally suspended in a

bomb bay The bomb bay or weapons bay on some military aircraft is a compartment to carry bombs, usually in the aircraft's fuselage, with "bomb bay doors" which open at the bottom. The bomb bay doors are opened and the bombs are dropped when over t ...

or horizontally mounted on a wing or fuselage hardpoint. The SD 250 was painted dark green, sky blue, or aluminum. The tail cone was striped with red and blue.

History

Design

See also

Gallery

References

External links