Over-all Length: 3.5 in.

Figure 39A – SD 2-kg "Butterfly" Bomb

CONSTRUCTION. The body of the bomb is a cylindrical cast iron casing. A fuze pocket is situated transversely in the side of the body. The SD 2A and SD 2B differ only in the method in which the fuze is secured in the bomb. The fuze is threaded into the SD 2A while it is secured in the SD 2B by a bayonet joint and two U-shaped safety clips.

The bomb body is encased in a thin sheet steel container made in four pieces – two end flaps and two pieces covering the sides of the bomb. (See figs 39A and 39B.) These parts are hinged together, the hinges being mounted with torsion springs tending to force the parts of the wings away from the body, but are prevented from opening until a safety pin is pulled when container opens. After release, the wings because of their air drag, rise to the upper end of the 6-inch wire cable connected to the fuze. The rotation of the wings relative to the bomb body arms the fuze. When fuze (41) A is employed in the bomb, the wings consist of two triangular shaped flaps.

SUSPENSION. 23 bombs in the AB 23 SD 2 container; 108 bombs in the AB 250-3 con-tainer; 6 bombs in the Mark 500 Roden container; 24 bombs in the AB 24 container.

COLOR. Body of bomb may be painted either black, lead-grey, red, yellow, or field grey. If the bomb is painted field grey it may have a 3/4-inch yellow band on the body, the wing assembly will be painted field grey with a yellow stripe on the inside and outside of the wings and may have a 3/4-inch red stripe at right angles to the yellow stripe on the wings. If the bomb body is painted yellow, the wings will be painted yellow with a 3/4-inch strip of red on the wings. In addition to the specific color combination given, the wings may be field grey or unpainted.

Figure 39B – SD 2-kg "Butterfly" Bomb