MIL-HDBK-1027/3B
b) Trench. Provide a narrow trench of sufficient depth for proper
cover; for cannon detachments, the trench shall be perpendicular to the line
of fire and to the rear of the cannon.
c) Concrete Walls. Make walls at least one foot thick (0.3 m) and
of sufficient height to provide cover for personnel standing erect.
d) Tractors.
Group tractors to afford proper protection
(temporary).
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