When operating in the jungle, mecha-nized infantry units may be given missions which they would not normally perform in other types of terrain. Such missions require special planning and coordination before and during the conduct of the mission.
ROUTE CLEARANCE AND SECURITY These operations are conducted when a route has been closed or unused. They are usually conducted so that supply activities may occur, but should not be confused with convoy escort operations, which require different tactics and techniques. Route security and clearance operations are oriented on a specific route and the surrounding areas, to insure that vehicular operations are not interrupted along that route.
Route clearance operations are con-ducted to eliminate the enemy along the road and to remove any explosives which may have been placed there. Whenever possible, route clearance is a combined arms effort involving as a minimum the use of armor, infantry, engineers, artillery, and Army aviation. Route clearance involves deliberate, detailed, and coordinated actions which are slow. The route must often be walked by mine-sweep teams, and the areas adjoining the route must be cleared by 6-12
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dismounted infantry. During route clearance operations, the mechanized infantry elements normally provide security forces for the combat engineer mine-sweep teams. The infantry is also used to clear the areas on either side of the road.
Route security missions are charac-terized by continuous activity to prevent the enemy from cutting the route or ambushing elements using it.
Patrolling is the key to route security, day and night. Patrols should be dispatched so there is no pattern. Patrols are usually squad-sized and are assigned specific areas of responsibility. They may at times move mounted but dismount where appropriate.
These areas of responsibility should extend to 1 kilometer each side of a route, for the mission is to prevent enemy mining or ambushes. A reserve force should be centrally located to be able to react in any direction.
Bridges or large culverts along roads are prime locations for enemy demolitions and ambushes. They must be kept clear and intact. A good way to do this is to ambush near them at night, and patrol from them during the day. Night observation devices should be used in ambush operations.
CONVOY MOVEMENTS
Coordination must take place before and during a convoy movement. Each patrol must know the time of entry and time of exit of each convoy, the numbers and types of vehicles, and whether the convoy has an armed escort. Just prior to the convoy’s approach, the security patrols intensify patrolling the areas immediately next to the road, and assume security positions along the known or suspected enemy avenues of approach. The convoy commander should have each patrol leader’s callsign and frequency, and notify him when he is entering and leaving the area.
The elimination of the enemy is the re-sponsibility of the unit through which the convoy is passing. If the convoy makes contact with the enemy, it should get out of the contact area as quickly as possible. The convoy commander will call the appropriate patrol leader or area commander and inform him of the contact. It is the area commander’s responsibility to relieve the convoy, reinforce friendly elements, and coordinate indirect fire or air support. The convoy, or its escort, fires on ambush locations until they can get out of the kill zone.
Convoy Escort. The purpose of a mechanized infantry convoy escort is to move with and secure a convoy. The convoy commander establishes the route, check-points, fire coordination, and communica-tions. He supervises rehearsal of actions on contact. He also identifies critical loads in the convoy and priorities for cross-loading. The convoy commander and escort should operate on a common radio frequency. Cross-loading spreads critical cargo in more than one vehicle. Convoys can use aerial reconnaissance aircraft as a part of the escort.
The mechanized infantry in their M113s and tanks, if available, both lead and follow the convoy. Wherever possible, the M113s will travel in pairs. If tanks are present, they normally lead the M113s. Communications among all convoy elements are essential. The convoy will travel according to the rate of the slowest vehicle.
The suppression and elimination of hostile fire is the responsibility of the escort commander. His first priority is to preserve the convoy and its contents. Upon being engaged by the enemy, the convoy will speed up to get out of the kill zone. Accompanying mechanized infantry and armor will assault by fire first, and maneuver as necessary. Any activity other than in the immediate area must be coordinated with the commander in whose area the ambush occurs, particularly 6-13
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if indirect fires or pursuit becomes neces-sary.
TANK-INFANTRY TEAMS Tanks and mechanized infantry are often restricted by jungle terrain, but where they can be employed, they complement each other well. For this reason, mechanized infantry and armored units are often teamed.
The two most common uses of tank-infantry teams in the jungle are for movements to contact and for convoy escorts.
Each must know how the other operates and the characteristics of all weapons systems. The tankers must always know where dismounted infantrymen are and the infantry must protect the tanks from close-in enemy attack.
VEHICLE RECOVERY
Mechanized infantry’s primary advan-tage is its ability to move rapidly as com-pared to nonmechanized infantry. This often will be curtailed by jungle terrain.
Every effort must be made to prevent M113s from becoming stuck or sustaining mechanical malfunctions that render them inoperative. The two most common occurrences are throwing a track and getting stuck in mud. The easiest way to prevent either is to precede each M 113 with a ground guide.
If an M113 becomes stuck, the primary recovery vehicle is the M578 vehicle track retriever (VTR). One is assigned to each company. It is equipped with a crane and boom, chains, and various other equipment, and it is usually located in the company trains. It should be escorted to and from a recovery site as it is not a combat vehicle.
Every effort should be made to recover vehicles by using another M113 before the M578 is used, unless an M578 is immediately available. The M578 should be moved only when needed because it has less traffic-ability than the M113, weighs more, and is
wider, which make movement in the jungle difficult for the M578.
Thrown Tracks. An M113 usually throws a track when the track is broken or detached from the drive sprockets. Repair time depends on a number of variables but usually varies from 45 minutes to 4 hours. The best preventive for thrown tracks is maintenance and good driving techniques. These involve keeping the track in good repair and under proper tension, the drive sprockets turned or changed, and supervising the drivers.
Mired M113s. Despite the M113s ability to move over most terrain, getting stuck in mud is not uncommon, especially when operating near rice fields or in areas of high rainfall. In these circumstances, ground guides are of little help. Infantry squads must develop expertise in expedient recovery methods.
Each M113 should carry tow cables and also chains. Since M578s will not always be available, the squad must know how to recover the vehicle without VTR support. In such instances, other M113s pulling in tandem may be necessary. A tank is even better because it is much heavier than an M113, is more powerful, and generally has greater traction, except in mud.
LOAD PLANS FOR THE M113 Load plans are designed to standardize loading of equipment and supplies and evacuation of priority items if the M113 is rendered inoperable. The plans further serve to standardize operations within a unit. Load planning requires a reverse sequence—that is, items that are used infrequently and are less critical to the mission than others are loaded first. Items that are used on a daily basis and are essential to mission accomplishment must be readily available.
When planning loads, consideration must also be given to maintenance. For example, radios should be easy to get to, and the engine compartment should not be blocked. The load plan diagram should also establish a 6-14
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numerical or alphabetical priority of equipment and supplies.