Recently received information permits supplementation of the brief description
in Tactical and Technical Trends, No. 29, p. 2 of
the German SD* 2-kilogram "butterfly" bombs.
Three types of fuzes are found in these bombs:
(1) 41 Fuze
Selector screw can be set for bomb to explode in the air Zeit (time) 3 seconds delay
after being armed, or on AZ (impact). The bomb is not armed unless 4 threads of the arming
spindle are visible. The fuze is screwed into place. The bomb is very sensitive if
selector switch is set at Zeit.
(2) 67 Fuze
Clockwork device which can be set for time delay up to 30 minutes. This fuze can be set for impact ignition also.
(3) 70 (A) and 70 (B) Fuzes
These are designed to function if the bomb is disturbed or vibrated
after falling, hence they are essentially anti-handling fuzes, if these
fuzes are armed, 3 threads of the arming spindle must be visible.
Fuzes 67 and 70 are pushed into the bomb and secured in position by two
projections which fit into slots in the casing.
All these fuzes should be treated cautiously. If there is uncertainty regarding
the type of fuze, do not approach for 30 minutes. To dispose of an unexploded
bomb, build a small sandbag wall around it and destroy in place. The bomb
may be detonated by placing a small charge beside it, or a rope may be used. If
the latter method is adopted, pull the rope from behind cover.
"Butterfly" bombs are dropped from a container holding 23 bombs. If the container
falls to the ground unopened or partly opened, with bombs still intact, the container
and contents should be detonated in place. If this is not feasible the container should
be carried to a trench or other convenient place and detonated therein. Lay the charge
on top of the container and tamp with earth. If the charge has not been well laid some
bombs may be blown clear. As a precaution, 30 minutes after detonating the container, search
the area for bombs and if any are found, detonate in place.
*SD designates a bomb which has a thick casing and achieves its effect chiefly by fragmentation.