You should describe or specify entanglement depths in terms of comparative effectiveness. Use tactical-wire entanglements with an equivalent in effectiveness to three belts of 4- and 2-pace double-apron fence whenever possible. Use protective wire in any type of entanglement provided its effectiveness is at least the equivalent of the 4- and 2-pace double-apron fence. Use supplementary wire with an effectiveness equivalent to that of the type of wire it supplements. It should be equivalent to tactical wire or equivalent to the type of protective wire being used if it connects the outer perimeters of protective wire at the flanks and rear.

Portability

By definition, fixed entanglements are erected in place and they cannot be moved unless completely disassembled.

Conversely, you can move portable, entanglements without complete disassembly. Portable entanglements have been developed for one of the following reasons:

l To permit assembly in rear areas with ease of transportation and rapid installation in forward positions

l For the temporary closing of gaps or lanes that can be reopened quickly for patrols or counterattacking forces

Figure 8-3.-Concertina roadblock.

Lanes and Gaps

Provide lanes and gaps for the passage of patrols, working parties, and attacking or counterattacking forces. When they are not in use, keep them closed with portable obstacles covered by fire. In barbed-wire zones, stagger lanes and gaps in a zigzag pattern.