Previous: H-7: Land Mines
H-8. Units create constructed obstacles with manpower or equipment without the use of explosives. Examples of constructed obstacles include:
- Ditches. Ditches across roads and trails are obstacles. Large ditches in open areas require engineer equipment.
- Log hurdles. Log hurdles act as “speed bumps” on roads. They are installed easily and are most effective when used in conjunction with other obstacles.
- Log cribs. A log crib is constructed of logs, dirt, and rocks. The logs are used to make rectangular or triangular cribs filled with dirt and rock.
- These are used to block narrow roads and defiles. Unless substantially built, log cribs will not stop tanks.
- Log posts. Log posts embedded in the road and employed in-depth can stop tracked vehicles. If they are not high enough to be pushed out of the way, posts can cause a tracked vehicle to throw a track if it tries to climb over. If employed with wire and mines, they also can slow enemy Infantry.
- Wire entanglements. Wire entanglements impede the movement of dismounted enemy Infantry, and in some cases, tracked and wheeled vehicles.
- Triple standard concertina is a common wire obstacle. However, there are other types, such as double apron, tanglefoot, and general-purpose barbed-tape obstacles.
- Figures H-2a through H-2c (pages H-5 through H-6) illustrate examples of wire and log obstacles. The materials used in constructing wire entanglements are relatively lightweight (compared to other obstacles) and inexpensive, considering the protection they afford.