Practice 8.5-lb. Mks I, II, and III (Service)

Body Construction: The Bombs Mk I and Mk III have a molded plastic body, which is made in three parts: a nose section housing the striker, a center section housing the de-tonator burster and filling plug, and a rear section which is hollow and closed at the after end. A perforated disc inside the rear section supports the end of  the detonator burster holder. The center part of the body is filled with lead-antimony balls, with the interstices between them, and all but a 10% air space in the rear section cone, filled with titanium tetrachloride, or gunpowder and magnesium turnings.

The striker head is retained in handling by a cotter pin, and shear wire. An annular groove inside the nose portion is filled with lead shot secured by wax.

The Bomb Mk II nose is fitted for an extension rod.

Tail Construction: The tail assembly consists of a tube molded into the rear section of the body, with a cylindrical strut attached to the tube by four fins.

Suspension: The bomb is suspended by a single suspension lug on a band, which fits in a groove in the body, and is secured in place by a securing screw.

Explosvie Components

Detonator burster – No. 28 Mk I consists of 10 grains fulminate of mercury and 7 C.E. pellets.

Main filling – Bombs Mk I and Mk II contain titanium tetrachloride, which, when expo-sed to the atmosphere, forms a cloud of white smoke, marking the point of impact. The Bomb Mk III has a flash filling consisting of gun-powder, and magnesium turnings.

Remarks: This bomb is designed for use against certain targets where a bomb is re-quired to break on impact without causing damage to the target. Because of its low ter-minal velocity, the bomb is only suitable for low-altitude bombing.

The Bombs Mk I and Mk II have smoke charges for day use, while the Mk III has a flash filling for night use.

Figure 55 - Practice 8-lb. Bomb Mk I