SD and Hollow Charge Bombs/Hollow Charge Nose Device
GERMAN EXPLOSIVE ORDNANCE - BOMBS, BOMB FUZES, ROCKET, LAND MINES, GRENADES AND IGNITER
Chapter 1
GERMAN BOMBS
INTRODUCTION

The following list gives the abbreviated designations used for the identification of German bombs, the full German designation and the English equivalent.

German Designation English

SC

Sprengcylindrisch

H.E. cylindrical general purpose.

SB

Sprengbombe

High capacity bomb.

SA

High capacity bomb.

SD

Spreng Dickwand

H.E. thick walled, semiarmor piercing, fragmentation.

SD (small)

Spreng Dickwand

Anti-personel.

SBe

Splitter Beton

Concrete fragmentation bomb.

PC

Panzerdurchschlag cylindrisch

Cylindrical armor-piercing bomb.

PD

Panzer Dickwand

Armor-piercing.

BT

Bomben Torpedo

Torpedo bomb.

SP

Splitter

Fragmentation (anti-personnel).

ZC

Zementcylindrisch

Cement cylindrical.

BLC

Blitzlichtcylindrisch

Photoflash.

KC

Kampfstoffcylindrisch

Chemical cylindrical.

NC

Nebelcylindrisch

Smoke cylindrical.

General

The three principal types of German demolition bombs are: "Spreng Cylindrisch"  (SC) or General Purpose bombs, "Spreng Dickwand" (SD) or splitter bombs (SAP) and "Panzer Cy-lindrisch" (PC) or armor piercing bombs. In addition to these three general types there are: SB and SA types of bombs for maximum blast, SBe concrete bombs, PD armor pier-cing bomb and the BT (Bomben torpedo) bomb. (See figs. 1 and 2.)

Figure 1 – Bomb Component Positions

Figure 2 – Paint Markings and Stampings

The SC or general purpose bombs are used primarily for general demolition work. The SC 250 and SC 500 may be fitted with two athwartships fuze pockets instead of the usual one. These two bombs are usually associated with time and protective fuzing. The other SC bombs are fuzed either instantaneously or with a short delay. SC bombs have thin parallel walls with a comparatively heavy nose. Usually they are of three pieces wel-ded construction. SC bombs have a loading factor of approximately 55 percent and are filled in most cases with cast TNT, powdered amatol or trialen. Bomb identification for the SC type is made easy by the presence of yellow paint on the tail cone.

The SB type of bomb is designed to give maximum blast effect. It has very thin walls and loading factor run as high as 80 percent. Fuzing is instantaneous.

The SD "splitter" or fragmentation bombs are used primarily against personnel, tanks, all types or armored and unarmored vehicles, and against other surface targets which are vulnerable to fragmentation damage. They are usually fuzed instantaneously and may have extension rods from the nose to actuate the fuze above the ground. The walls are thick, the thickness being uniform throughout the sides with a slightly heavier nose. They are usually forged in one piece. They have a loading factor of approximately 35 percent and are filled with TNT, amatol or trialen. Bombs may be identified by the presence of red paint on the tail cone. (This should not be confused with the base coat of red lead which is used on all German bombs.)

SD (small antipersonnel bombs). A special grouping of these is desired, for they are a very distinctive group and not just a miniature model of the larger type. Bombs have thick walls and a low loading factor. A mechanical instead of electric fuze is used in most of these bombs and bombs are usually carried in containers. SC bombs of this type are so designated, but it seems they might more correctly be called SD to keep classification uniform.

SBe or concrete bombs are used for the same purpose as SD's. They have thick con-crete walls reinforced with steel. Loading factor is around 20 percent and a low power percent and a low power explosive is normally used.

The PC or armor-piercing bombs are using primarily against ships and fortifications. They are fuzed with a short delay for penetration. PC bombs are slightly streamlined with a heavy hose and thick walls. The thickness of the walls decreases toward the base of the bomb. They are made of cast steel and the nose is specially hardened. PC bombs have a loading factor of approximately 20 percent and are filled with a TNT wax mixture. PC bombs may be identified by the presence of dark blue paint on the tail cone. PC bombs have been used as SD's for fragmentation and fuzed instantaneously; if so, the dark blue may be over painted with red.

The PD is even more exclusively armor piercing. Bombs are thinner, longer, have thicker case and a lower loading factor.

BT. The BT (bomben torpedo) was put into production during the last 2 months of the war, but was never used operationally. It is designed along the lines similar to a torpedo except for the after section where there are three large tail fins. The missile has no pro-pulsion except that induced be gravity and the forward motion of the mother aircarft.

SA 4000 (Experimental) is a very large high capacity bomb. The loading factor is about 80 percent. It was never used operationally against the allies.

Misc. Plane Destroying Bombs. The aircraft towed paravane bomb is small 2-kg bomb tow-ed by a plane. The plane destroying bomb is a small charge with a pull type igniter and safety fuze.

Coloring

Bombs which are carried in internal bomb racks (up through 500 kg) are usually colored dark green. Bombs which are carried in external bomb racks (1,000 kg and over) are usually colored dark sky blue. Color may also be controlled by the conditions of the bomb stowage. Aluminum, tan, buff, etc., are colors that may be used.

Typical Bomb Explosive Train

The fuze is located in an athwartship fuze pocket extending the full internal diameter of the bomb. (See fig. 3.) The fuze is usually held in the top of the fuze pocket by a locking ring and a locating ring. Threading into the bottom of the fuze is a steel case called the gaine. The gaine is filled with a P.E.T.N.-wax mixture. A small pellet of lead azide and lead styphnate mixture is positioned in the top of this gaine. These pellets may be of granular TNT. In bombs with powdered fillings, a column of granular TNT pellets is placed longitudinally in the bomb adjacent to the fuze pocket.

Figure 3 – Fuze Pocket in Bomb

Tail Construction

Two tail types are used. The first type, a sheet steel tail, is usually made in four piece to form a cone with four fins. The fins may be unbraced, braced with tubular struts, or bra-ced with a cylindrical strut (ring). The second type is of magnesium alloy. The cone and four fins are cast in one piece. The fins may be braced with a cylindrical strut of the same material.

Suspension

Bomb up to and including some of the 500 kg types can be suspended either horizontally or vertically. (See fig. 4.) The remaining 500's and all larger types are suspended hori-zontally. All vertical suspension is by an eyebolt threaded into the nos of the bomb. Hori-zontal suspension is by an exebolt for the 50 kg series, either an eyebolt or a threaded T- Type lug for the 250 kg and 500 kg series, and by means of an H-type lug for the lar-ger series bombs. The H lug is secured either to a carrying band or directly to the bomb body. The SC 1000 and SC 1200 type bombs have been using a U bolt secured to the carrying band on the latest model.

Figure 4 – Suspension

Kopfring

Kopfrings (nose rings) are sometimes fitted to the nose of SC bombs to prevent exces-sive penetration against land targets and to prevent ricochet against sea targets. (See figures 5A and 5B.) Kopfrings may also be found on the SD 70 and SD 1700 bombs when they are used against abovementioned targets.

Antiricochet Plates

The antiricochet plates are used for the same general purpose as the kopfring but are entirely different in construction. Type I, which is used only on the SC 250 kg bombs, is constructed of a conical cup and a dished plate welded to it. (See fig. 6.) The conical cup is of 3/16 inch steel and designed to fits as a sheath over the nose of the bomb. A dished plate, 10 inches in diameter, fits over the cup and is welded to it. Eight stiffening ribs, also of 3/16 inch steel, are welded between the plate and the cup. The entire as-sembly is attached to the nose of the bomb by means of a threaded bolt which passes through a hole in the apex of the cone.

Type II is used on the SC 50 kg bombs. A circular plate, 5 3/4 inches in diameter and 15/16 inch thick, is machined conically to fit over the nose of the bomb. Welded to this plate is a circular cup, 2 11/16 inches in diameter and drilled centrally to take a bolt for securing the entire assembly to the bomb.

Figure 6 – Antiricochet Plates

Dinort Rods

Dinort rods are secured to the nose of the SD type bomb and used to obtain a "daisy cutter" effect on impact. There are two types: steel rods and wood rods. (See fig. 7.)

Steel Rods. The rod consists of a drawn steel tube with a circular steel plate welded to the base and a steel cup welded to the top. A threaded lug is welded to the upper end of the tube and passes through a hole in the cup. This lug screws into the suspension lug socket at the nose of the bomb.

 

Steel Rods

 
  SD 50 SD 70 SD 250 SD 500  
  Length of Rod

23.6"

23.6"

14.8"

14.8"

 
  Diameter of Rod

1.75"

1.75"

2.75"

2.75"

 
  Diameter of Plate (base)

4.7"

4.7"

9.45"

12.6"

 
  Diameter of cup (top)

3.6"

5.5"

 

Wooden Rod. The rod consists of the square, center stick with two square pieces of wood nailed to the base. Two U-shaped steel plates welded together, are secured to the upper end of the main member by light woodscrews. A bolt, welded to the plates, is threaded to screw into the nose suspension lug socket at the nose of the bomb.

 

Wooden Rods

 
  Over-all length

22.6"

 

 
  Width of center setction

2.25" (square)

 

 
  Widt of base

Smaller piece 4" (square)

Larger piece 4.25"

 

Figure 7 – Dinort Rods

SD and Hollow Charge Bombs/Hollow Charge Nose Device