Military

PASSAGE
OF LINES

        A passage of lines is an operation in which one unit moves either forward or rearward through positions held by another friendly unit. During a passage of lines, both units are temporarily concentrated in a small area and are extremely vulnerable. For such passage to occur with the least disruption of either unit's tactical mission, the commanders must thoroughly coordinate troop movement, troop positions, combat support, and combat service support.

        Planning. Upon receipt of an order to conduct a passage of lines, the company commander of the passing company initiates his troop leading procedure (chap 2). He must contact the stationary company commander and arrange for a specific time and place for coordinating the passage. If possible, the company commanders, platoon leaders, and fire support team (FIST) chiefs of the two companies should attend the coordination meeting. In some situations (in a delay, for example), the company commander of the passing company may have his executive officer (XO) and a quartering party conduct the coordination.

        The commanders of the two companies must plan for and coordinate:

• Exchange of enemy information.

• Reconnaissance of the area.

• Passing company's scheme of maneuver.

• Exchange of communications information:

• Recognition signals to be used.

• Use of guides and traffic control.

• Security measures to be used during the passage.

• Control measures to be used during the passage.

• Fire support.

• Transfer of responsibility/actions on enemy contact.

• Combat service support.

        After the coordination meeting, the commanders and platoon leaders should conduct a reconnaissance of the area, return to their units, complete their plans, and issue orders as appropriate.

        Control Measures. The control measures used during a passage of lines normally include:

• Contact point. The stationary company commander designates contact points where the two companies will make initial contact. There will normally be a primary and an alternate contact point. However, he may decide to use multiple contact points (one per platoon).

• Passage lanes. The stationary company commander normally assigns the passing company a primary and an alternate passage lane. In some situations, he may assign the passing company multiple passage lanes (one per platoon). The passing unit(s) must move within its assigned passage lane when passing through the stationary company. The lanes should pass through unoccupied areas between elements of the stationary company or to the company's flank.

• Passage points. The stationary company commander designates a passage point in each passage lane to increase control. Each passing unit must pass through its assigned passage point. This allows the stationary company to monitor movements of friendly elements more closely and helps reduce the possibility of enemy infiltration.

• Release points. The stationary company commander designates a release point at the end of each passage lane. At each release point, the guide from the stationary company releases control of the passing unit to its respective leader.

• Assembly area (rearward passage). The stationary company commander designates an assembly area (for the passing company to use) to the rear of his company. This is especially useful when there are multiple passage lanes.

        Reconnaissance. After the coordination meeting, the commanders and leaders should conduct a reconnaissance of the area. They must determine:

• Passage lanes.

• Locations of the passage points.

• Locations of any obstacles.

• Locations of the release points.

• Location of the assembly area (for a rearward passage).

• Disposition and actions of the stationary company.

• Locations of contact points.

• Locations of the combat support and combat service support elements (command post, observation posts, trains, aid stations, mortars, tube-launched, optically tracked, wire-guided [TOW] missiles, and tanks).

        Communications. The commanders should exchange callsigns, frequencies, codewords, pyrotechnic signals, and challenge and passwords. They must also plan for recognition signals that will be used to help identify the two units. This is especially important during limited visibility operations.

        Guides and Traffic Control. The stationary company should provide guides to link up with the passing company at the contact point(s) and guide it through the passage lane(s). The passing company commander must tell the stationary company commander how many units, personnel, and vehicles will be passing through. If multiple lanes are used, this information should be broken down by lanes. This helps the stationary commander determine the number of guides and other traffic control measures needed. The passing company should have a representative at

each passage point to identify and account for the personnel and vehicles passing through each point, and to notify the passing company commander when all personnel and vehicles have passed each point.

        Security. The commanders must insure that their reconnaissance and other preparation activities do not reveal their plans to the enemy. They should select covered and concealed locations for the contact points, passage points, release points, and assembly areas. The passage lanes should also provide cover and concealment. When possible, the passage should be conducted during periods of limited visibility. The stationary company's security activities (patrols and observation posts) should continue to operate as normal.

        Passing Company's Scheme of Maneuver. The passing company commander should explain his company's scheme of maneuver to the stationary company commander. This may help the stationary company commander determine how he can best support the passing company.

        Fire Support. The company commanders must coordinate their plans for fire support. The stationary company should support the passing company with direct and indirect fire until they are masked by the passing company. The FIST chiefs of both companies should exchange target lists and, if possible, collocate during the passage.

        Transfer of Responsibility/Actions on Enemy Contact. The responsibility for the area forward of the stationary company should be transferred at an agreed upon time. Normally, in a forward passage, the commander of the passing company assumes responsibility for the area at, or prior to, the time of passage or time of attack. This allows him to control all fire and maneuver in the area. If the responsibility for the area is transferred prior to the passage, the

commander of the passing company normally assumes operational control of the security elements forward of the forward edge of the battle area (FEBA) belonging to the company being passed through. In the rearward passage, the responsibility for the area forward of the stationary company changes from the passing company commander to the stationary company commander when the passing company passes a specific location (designated phase line) or at a specified time. Coordination and control are facilitated if the boundaries of the two units coincide. In either a forward or a rearward passage, both commanders must coordinate their plans for reacting to enemy contact during the passage.

        Combat Service Support. In a forward passage, the stationary company should provide combat service support to the passing company. This normally includes evacuating casualties, handling prisoners of war, recovery and evacuation of vehicles, and resupply of fuel and ammunition. In a rearward passage, and when feasible, the passing company should provide combat service support to the stationary company.

        Conduct of the Passage. At the scheduled time, the passing company approaches the contact point(s) and exchanges recognition signals with the guide(s) from the stationary company. After the necessary information is exchanged, the guide(s) takes the passing company through the passage lane(s) and releases it at the release point(s). As the passing company reaches its passage point(s), its representative(s) contacts the representative(s) from the stationary company and exchanges the necessary information. Even though leaders are coordinating, movement should be continuous. Both company commanders and both FIST chiefs should be collocated at a point from which they can observe critical areas, make timely decisions, and issue necessary instructions.

RELIEF
IN PLACE

        A relief in place is an operation in which one unit (relieving unit) relieves another unit (relieved unit) and assumes the relieved unit's responsibilities. A relief in place may be conducted to--

• give a unit a break from combat when it has taken heavy losses,

• relieve the stress of prolonged operations in adverse weather or terrain, or

• allow the relieved unit to move to another location in order to conduct another operation.

        The relief is normally conducted while the relieved unit is in a defensive posture. The commander of the relieving unit should insure that his task organization conforms as closely as possible to that of the relieved unit. He should make changes to the defense only after the relief has been completed. This reduces the confusion and insures that the defense is not unnecessarily weakened by any changes during the relief.

        Planning. Upon receipt of an order to conduct a relief in place, the company commander of the relieving company initiates his troop leading procedure (chap 2). He must contact the relieved company commander and arrange for a specific time and place for coordinating the relief. If possible, the company commanders, XOs, platoon leaders, and FIST chiefs of the companies should attend the coordination meeting. The company commanders may have the platoon forward observers (FO) attend the meeting.

        The commanders and leaders of the two companies must plan for and coordinate:

• Exchange of enemy information.

• Reconnaissance of the area.

• Exchange of communications information.

• Use of guides and liaison personnel.

• Security measures to be used.

• Control measures to be used. o Fire support.

• Sequence of relief.

• Traffic control.

• Transfer of responsibility.

• Transfer/exchange of equipment, supplies, ammunition, and minefields.

        After the coordination meeting, the commanders and leaders should conduct a reconnaissance of the area, return to their units, complete their plans, and issue orders as appropriate.

        Control Measures. The control measures used during a relief in place normally include:

• Assembly areas. The relieved company commander designates a company assembly area for his company and a platoon assembly area for each of his platoons. The relieved platoon leaders designate squad assembly areas for their squads.

• Contact point. The relieved company commander designates a contact point where the two companies will make initial contact. This is where the company guide (provided by the relieved company) links up with the relieving company. There should be a primary and an alternate contact point.

• Release points (RP). The relieved company commander designates the release points to be used by the relieving company. He designates a platoon RP for the company and also a squad RP for each of the relieving platoons.

• Routes. The relieved company commander selects the relieving company's route from the contact point to the platoon RP. He also selects a route for each relieving platoon to use when moving from the platoon RP to its respective squad RP. Each relieved platoon leader then selects a route for each relieving squad to use from its platoon's squad RP to its defensive position.

        Each relieved squad leader selects his squad's route to its squad assembly area.

        Each relieved platoon leader selects a route for each of his squads to use when moving from its squad assembly area to his platoon's assembly area. The relieved company commander selects a route for each of his platoons to use when moving from its platoon assembly area to the company assembly area.

        The relieved company commander must insure that all routes are coordinated between the two companies, and that troop movement in the area is controlled.

        Reconnaissance. After the coordination meeting, the commanders and leaders of both companies should conduct a reconnaissance of the area. They must determine:

• How the relieved company is disposed on the defensive position.

• Locations of the assembly areas. o Locations of the release points. o Location of the contact point.

• Routes to be used.

• Locations of any obstacles.

• Locations of the combat support and combat service support elements (command post, observation posts, trains, aid stations, mortars, TOWs, and tanks).

        Communications. The commanders must exchange call signs, frequencies, codewords, pyrotechnic signals, and challenge and passwords. During the relief, both companies should be on the relieved company's radio net. The relieved company should maintain its normal level of radio traffic; the relieving company should maintain radio listening silence. The companies should use wire nets as much as possible. When the relief is complete, and on a predetermined signal, the relieving company switches to its assigned frequency.

        Guides and Liaison Personnel. The relieved company should provide guides to link up with the relieving company and guide its subelements through the relief. In addition to the company guide, guides are normally provided for the platoons, squads, mortar section, TOW section, tanks (when present), and headquarters elements. The

relieved company may also provide liaison personnel to remain with the relieving company until the relief is complete and its personnel are familiar with the area.

        Security. Normal activities should be continued to deny the enemy knowledge of the relief. Local security (observation posts [OP] and patrols) should be maintained by the relieved company. These should be the last troops to be relieved. The relief must not be mentioned in the clear on field phones or radios. The relief must be executed in the shortest possible time to reduce troop massing. The company commanders and their subordinate leaders must maintain adequate dispersion between units, enforce light and noise discipline, and control movement. The relieved company should leave its surveillance and radar teams in position until the relief is complete. If the relieving company is mechanized infantry, it should dismount to the rear so as not to jeopardize secrecy. It then moves forward on foot. Its carriers should not move forward until the relief of all dismounted troops is complete.

        If the relieved company is mechanized infantry, it should leave its vehicles in position until the relief of all the dismounted soldiers is complete. It then moves the vehicles to link up with its soldiers. Infantry companies should also complete the relief of all dismounted soldiers prior to moving vehicles into or out of the area.

        Fire Support. The company commanders must coordinate their plans for fire. The relieving company should use the relieved company's TOW positions initially. The relieved company commander may have his TOW section and mortar section remain in position until the relief is complete, and then move to the rear. The FIST chief of the relieved company should pass all of his fire support information, to include his target list, to the FIST chief of the relieving company. The commanders should collocate their FIST chiefs during the relief.