The 14 kg No 2 Mks 1, 2 and 3 practice bombs are for
use in practising those delivery techniques adopted for
1000 Ib ballistic bombs. The Mks 1 and 2 produce white
smoke and flash on impact and the Mk 3 is used when
there is no requirement for smoke and flash. The Mk 1
and 2 differ only in the material used to manufacture
the tail. The Mk 3 is an inert bomb with an aluminium tail. The bombs are released from a No 122 series ERU.
The body is machined to a profile and the nose is
cupped internally to assist in the retardation of the
bomb on impact and to shield the striker against impact
if the bomb is accidentally dropped on to a hard surface.
A frangible nose cap is fitted to the nose end of the
body. The body is machined internally throughout its
length to house a steel striker shaft in two guide
bushes.
The bomb has a hollow, cast aluminium alloy tail unit
with four fins. The forward end is drilled to house a
safety pin and allow for inspection. It is machined
internally to receive the cartridge container. A
dimensionally and visually similar tail unit is fitted to
the No 2 Mk 2 bomb; this unit being constructed of
moulded plastic material.
On impact the frangible nose cap shatters. The cupped
steel nose retards forward movement of the bomb and
inertia, acting on the cartridge container compresses a
three legged leaf spring and drives the cartridge
container on to the striker, igniting the charge. On soft
targets, i.e. mud and water, the striker shaft is forced
backwards, compressing the leaf spring and so firing the
percussion cap. The resulting flash and smoke escape
from the open end of the tail unit.