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21st Century Operations Using 21st Century Technologies

Coordinating Military Deployments on Roads and Highways:
A Guide for State and Local Agencies

This publication is an archived publication and may contain dated technical, contact, and link information.


Appendix B. Military Convoy Movement Facts

The following information and terminology will assist State and local agency representatives who support military convoy operations in understanding the movement of convoys.

Organizational Elements

To facilitate command and control, vehicles in a convoy are organized into groups. A convoy may be as small as a six-vehicle march unit or as large as a 300-vehicle column. A convoy commander can better control a convoy if it is broken into smaller, more manageable groups. Whenever possible, convoys are grouped along organizational lines, such as platoon, company, and battalion.

The three organizational elements of a convoy are a march column, a serial, and a march unit (Figure B-1):

  • A march column is approximately a battalion-to-brigade-size element. Each column has a commander. A march column consists of two to five serials.
  • A serial consists of elements of a march column (convoy) moving from one area over the same route at the same time. All the elements move to the same area and are grouped under a serial commander. The serial commander is directly responsible to the convoy commander. A serial may be divided into two or more march units.
  • A march unit is the smallest organized subgroup of the convoy; it usually does not exceed 20 vehicles. It falls under the direct control of the march unit commander.
drawing showing the organization of a convoy: a march column composed of two serials, each composed of two march units, shown by drawings of several convoy vehicles

Figure B-1. Organizational Elements of a Convoy

All columns, serials, and march units, regardless of size, have three parts: a head, a main body, and a trail (Figure B-2). Each of these parts has a specific function.

drawing showing the elements of a march column: a main body, shown by drawings of several convoy vehicles, a convoy vehicle designated as "head" in front of the main body, and two vehicles designated as "trail" following the main body

Figure B-2. Elements of a March Column

The head is the first vehicle of each column, serial, or march unit. Each head should have its own pacesetter. The pacesetter rides in this vehicle and sets the pace needed to meet the scheduled itinerary. The officer or noncommissioned officer at the head ensures that the column follows the proper route.

The main body follows immediately after the head and consists of the majority of vehicles moving as part of the convoy.

The trail is the last sector of each march column, serial, or march unit. The trail officer is responsible for recovery, maintenance, and medical support. The recovery vehicle, maintenance vehicles, and medical support vehicles/teams are in the trail. The trail officer is responsible for march discipline, breakdowns, straggling vehicles, and control at the scene of any accident or incident involving his march unit until the arrival of civilian authorities.

Convoy Formations

The convoy must be organized to meet the deployment mission requirements and provide organizational control. The convoy commander decides how the convoy will be formed for movement, taking into consideration such factors as the planned route, distance to the destination, types of vehicles/equipment, and travel conditions (weather, time of day, etc.). The three basic types of formations are close column, open column, and infiltration. They are as follows:

  • Close column. This formation provides the greatest degree of convoy control. It is characterized by vehicle intervals of 25 to 50 meters and speeds under 25 mph. Close column is normally used during limited visibility or on poorly marked or congested roads.
  • Open column. This is the preferred formation during movement. It is characterized by vehicle intervals of 300 feet or more and speeds in excess of 25 mph. The open column formation is normally used on well-marked open roads with good visibility.
  • Infiltration. This formation has no defined structure. Vehicle intervals and speeds vary. This type of formation is normally not used during movement. Infiltration should be used only as a last resort in extremely congested areas, when the convoy becomes unexpectedly dispersed or when the mission dictates.

Other Terms

Distance. Distance factors, listed below, are expressed in kilometers or miles:

  • Length is the length of the roadway the convoy occupies, measured from the front bumper of the lead vehicle to the rear bumper of the trail vehicle.
  • Road space is the length of a convoy plus any additional space needed to avoid conflict with leading and following traffic.
  • Gap is the space between vehicles (vehicle interval) or between elements of a convoy (column gap). It is measured from the rear of one element to the front of the following element.
  • Road clearance distance is the distance that the head of a convoy must travel for the entire convoy to clear a given point along the route. It is the sum of the convoy's length and road distance.

Time. Time factors, listed below, are expressed in hours or minutes:

  • Pass time is the time required for a convoy or a subgroup to pass a given point on the route.
  • Time space is the time required for a convoy or one of its subgroups to pass any point along the route.
  • Time gap is the time between vehicles or elements as they pass a given point. It is measured from the trail vehicle of one element to the lead vehicle of the following element.
  • Time lead (headway) is the time between individual vehicles or elements of a convoy, measured from head to head, as they pass a given point.
  • Time distance is the time required for the head of a convoy or any single vehicle to move from one point to another at a given rate of march.
  • Road clearance time is the total time a convoy or an element needs to travel over and clear a section of road. Road clearance time equals the pass time plus the time distance.

Pacesetter. The convoy commander will designate a pacesetter for the convoy. The pacesetter is in the first vehicle in the march element, normally the slowest, heaviest vehicle, excluding oversize/overweight vehicles. The pacesetter will:

  • Maintain the rate of march established by the convoy commander
  • Meet all established times
  • Inform the convoy commander of any obstacles or hazards, such as construction, detours, or other obstacles, that may cause a deviation from the established route
  • Coordinate with DPS escort officers, as appropriate.

Trail Officer. The trail officer is positioned at the rear of a march element. He checks and observes vehicles and keeps the convoy commander informed on the status of vehicles that fall out of the convoy. He oversees all maintenance, recovery, accident investigation, medical aid, and disposition of disabled equipment.

Convoy Identification

Convoy Control Number. Each convoy is identified by its convoy control number (CCN), which is assigned by the ITO where the convoy originates. The CCN identifies the convoy during its entire movement. It is placed on both sides of each vehicle in the convoy. The CCN is also placed on the top of the hood of the first and last vehicles of each march element.

The CCN has 10 digits. The first two digits identify the location (post or State) from which the convoy originates. The next four digits represent the julian date (e.g., 5180 is the 180th day in 2005 or 30 June 2005). The next three digits are the sequence number, followed by a single digit designating the type of movement.

The movement designators are as follows:

  • Outsize/overweight vehicles—S
  • Explosives—E
  • Hazardous cargo—H
  • All other convoys—C.

Placarding. All convoy vehicles transporting hazardous materials must be appropriately placarded (Figure B-3). Placarded vehicles must also abide by Federal and State laws.

drawing showing the placement of hazardous material placards on the side, front, and rear views of a convoy vehicle

Figure B-3. Placard Placement on Convoy Vehicles

Vehicle Identification. The first vehicle (pacesetter) in each element of the convoy must have on its front a sign with 4-inch black letters on a yellow background reading CONVOY FOLLOWS. The last vehicle of each convoy element will have on the rear a sign reading CONVOY AHEAD. CONVOY AHEAD signs are not on maintenance or medical vehicles unless the vehicle's purpose is to represent the end of the convoy.

Each march element of a convoy must be marked with flags 12 inches high and 18 inches long. The lead vehicle is fitted with a blue flag and the rear vehicle with a green flag. The flag is mounted on the left front of the lead and trail vehicle so that it will not interfere with the driver's vision or with any functional component.

An example is FE 2234 039 C, a convoy leaving from Fort Eustis, VA, on 22 August 2002. It is the 39th convoy of the day and is a regular convoy without any special requirements.

The vehicles of the column, serial, and the march unit commanders must carry on the left front bumper a white and black flag. Trail party vehicles will carry an international orange safety flag. Local police or MP escort vehicles will not display convoy identification flags.

A rotating amber warning light is placed on cranes (wreckers), oversize or overweight vehicles, and the first and last vehicles in a convoy. The lights are on at all times when the convoy is operating outside a military installation.

Vehicle Placement. The placement of the vehicles in an organizational element of a convoy is determined by many factors. A major factor is the danger of rear-end collisions. To reduce the possibility of injury to personnel, vehicles transporting troops should be placed in the first march unit of the main body of the convoy. When empty trucks or trucks loaded with general cargo are available, they should be used as buffer vehicles between those transporting personnel and those loaded with hazardous cargo. Other factors to consider include the following:

  • Vehicles that require the longest unloading time should be near the front of the main body of the convoy. This will shorten turnaround time.
  • If the convoy consists of vehicle-trailer combinations, there should be one prime mover without trailer (bobtail) per 10 vehicle-trailer combinations to support recovery operations.
  • Vehicles transporting hazardous cargo should be in the last serial of the convoy but not in the trail party.

Safety Equipment and Warning Devices. While moving at night or during periods of reduced visibility, lead, trail, and oversize/overweight vehicles will operate four-way flashers. Convoy vehicles will also display reflective L-shaped symbols 12 inches long and 2 inches wide at the lower corners of the vehicle's body.

(Headlights of all vehicles moving in convoy or halted on road shoulders must be on low beam at all times except where prohibited by local ordinances. While halted on shoulders, vehicles equipped with emergency flasher systems must also have these lights operating. The following safety equipment is needed in all vehicles:

  • An approved fire extinguisher
  • An approved first aid kit
  • One set (pair) of tire chains when snow or ice conditions may be encountered
  • An approved highway warning kit.

Road guides must wear high-visibility devices such as a reflective vest. Baton flashlights must also be provided when the convoy operates during darkness or when visibility is reduced to 500 feet or less.

Highway Convoy Operations

Main convoy routes, such as major highways and expressways, are usually characterized by heavy, fast-moving traffic. Entering, driving, and halting on these routes are extremely critical operations that require prior planning and coordination with civilian authorities. Convoy commanders and drivers require special training and field practice to operate specialized equipment on major public highways.

Entering Convoy Routes. The convoy should depart the assembly area at the time given in the movement order. Police support will reduce interference with other traffic and ensure the integrity of the convoy. The "close column formation" should be used when moving from the assembly area to the main convoy route.

This same practice should be followed when the convoy is leaving any staging or assembly area.

Note: Risk can be significantly reduced when civilian police assist by controlling civilian traffic. If a civilian police escort is not available, MPs or other military personnel may need to fill this role. However, coordination with local law enforcement will be needed to confirm jurisdiction and authority on public highways.

Entering Expressways. Most expressways are equipped with entrance and exit ramps and acceleration and deceleration lanes that are designed to allow vehicles to enter and leave without interfering with other traffic. When used properly, these lanes greatly reduce the risk of traffic accidents and help in the movement of the convoy. The following instructions apply both to the initial point of entry to the expressway and the return to it from a rest/halt area:

  • As mentioned previously, civilian police assistance should be obtained to direct convoy vehicles onto the expressway and to control civilian traffic. When civilian police are not present, MPs or other military personnel should be used to signal military vehicles when it is safe to enter the expressway. Military traffic should not interfere with civilian traffic.
  • Before driving onto the entrance ramp, the distance between convoy vehicles should be reduced to a maximum of 20 yards. This reduces the time the entrance ramp is blocked to normal traffic.
  • Upon reaching the acceleration lane, convoy speed should be increased to equal as closely as possible that of other traffic on the expressway. The maximum speed authorized for military vehicles on expressways is 50 mph.
  • Military vehicles moving on controlled access highways should maintain the posted minimum speed or 40 mph if a minimum speed is not posted. Vehicles that cannot maintain the posted minimum speed will be routed over an alternate, noncontrolled access road.
  • Under no circumstances should the posted maximum speed limit be exceeded.
  • When moving into the traffic lane and before merging, the driver must ensure that lanes are clear of oncoming traffic. After entering the traffic lane, drivers should not immediately try to move to the prescribed distance for expressway convoy operations but continue for a distance equal to the road space of the column. Drivers should then gradually attain the distance between vehicles for expressway driving or as given by the operation order and final briefing.

Note: Vehicles must not slow down or close up while in a traffic lane of the expressway.

Driving on Expressways. All vehicles must remain in the right-hand lane once the convoy has entered the expressway. If the right lane is reserved for traffic exiting at the next exit ramp, the convoy should use the next adjacent lane. Drivers are trained to stay alert and to be prepared to slow down or take other evasive action to avoid vehicles entering the expressway from acceleration lanes.

Rest and Meal Halts on Conventional Highways. On conventional highways with adequate off-shoulder parking space, rest and meal halts normally do not present a problem. However, the following precautions should be taken:

  • Do not select rest areas located in urban or heavily populated areas
  • Avoid areas on curves or reverse sides of hills
  • Leave enough room to allow the vehicles to park off the paved portion of the road and return to the road safely
  • Maintain a minimum distance of 3 feet between parked vehicles
  • Place warning kit devices at the head and tail of the column unless the vehicles are completely off the highway and shoulder
  • Leave the flashing warning lights in operation and the headlights on
  • Post a guard behind the trail party with proper warning devices to alert, but not direct, approaching traffic
  • Do not permit convoy personnel, with the exception of guards at the head and tail of each halted march element, on the traffic side of vehicles except to perform prescribed maintenance
  • Make sure drivers and assistant drivers perform prescribed at-halt maintenance and check the security of cargo and report deficiencies that cannot be corrected by the vehicle crew to the serial commander
  • Post guards at least 50 yards behind the last vehicle to warn traffic when departing a rest area. When police support is provided, this step may not be required. Convoy vehicles should return to the highway as rapidly and safely as possible.

Refueling Halts. Most military vehicles can travel 300 miles without refueling. Vehicles with limited range should be refueled during the noon meal halt as well as during regular refueling halts.

Note: In determining when to refuel, the vehicle with the least operating range is used as the baseline. This prevents any vehicle in the convoy from running out of fuel.

Toll Roads, Bridges, and Tunnels. A convoy representative should be assigned to clear the convoy at the initial entrance to toll facilities and any intermediate points where tolls are collected. When possible, toll tickets or electronic passes should be obtained before the convoy departs from its point of origin. When this is not feasible, the convoy representative should arrive at the toll facility entrance well ahead to coordinate passage and arrange for the uninterrupted movement of the convoy through the toll facility.

Certain toll authorities, especially at tunnels, may provide an escort through the toll facility. The DMC should coordinate with the toll authority to facilitate convoy movement, as appropriate.

Halts Due to Mechanical Failure. If a vehicle develops mechanical trouble, the driver should activate the appropriate turn signal to alert the vehicle behind him and move onto the shoulder or into a parking area and wait for the arrival of the trail party. Heavy Equipment Transport System (HETS) vehicles should not use the roadway shoulders due to their size and weight. The remaining convoy vehicles should continue past the halted vehicle, leaving maintenance to be done by the trail party.

A vehicle disabled because of mechanical failure should immediately be moved from the traffic lane to a location where it will not be a hazard to other traffic. If a breakdown occurs while driving on an expressway or highway, the driver should take immediate action appropriate to the time of day and degree of visibility in the area.

Sunset to Sunrise: During the time that lights are required (sunset to sunrise) and when forward visibility is reduced to 500 feet or less, a reflector should be placed either in the obstructed lane or on the shoulder of the road if the vehicle is on or over the shoulder. The reflector should be placed to face the traffic using that lane. This should be done before attempting to repair the vehicle.

Sunrise to Sunset: During the time lights are not required (normally sunrise to sunset), red flags or reflectors with mounted flags should be placed at the distances prescribed for night. Because most warning kits contain only two flags, the reflector placed 10 feet behind the vehicle will not have a flag.

Attention to Public Safety

Commanders should locate disabled vehicles to minimize impact on the traveling public and damage to roadway infrastructure. Certain military vehicles can be safely halted on roadway shoulders; however, oversize/overweight vehicles should never be stopped on shoulders.

Commanders are instructed not to use military personnel to warn drivers by manual flagging except when emergency warning devices do not give adequate warning.

Accident Procedures. If an accident occurs, every effort must be made to reduce its effects and to keep the convoy moving. In the event of an accident, the following steps should be taken:

  • Keep moving. Only the vehicle immediately behind the damaged vehicle should stop and render assistance.
  • The affected vehicle should wait for assistance. The vehicle should not be moved until civilian police have completed an accident investigation. Any accident should be reported to civilian police.
  • Clear the traffic lane. The crew of the affected vehicle should make every effort to clear the traffic lane as soon as possible. In case of injuries, the crew of the assisting vehicle may be required to move the damaged vehicle.
  • Prepare the accident reports (for military and State or local law enforcement).

Vehicle Accidents Causing a Fire or Creating an Electrical or Fire Hazard. Motor convoys travel mostly over highways in rural areas. Fire departments in these areas are widely scattered, and firefighters may have to travel a long distance to respond to an emergency. This means that convoy control personnel will probably be the first to arrive at the scene of the accident and must be prepared to rescue endangered personnel, attempt to control a fire, or take steps to prevent one. If the accident results in a vehicle fire, convoy supervisory personnel should take the following actions:

  • Halt the control vehicle a safe distance from the fire. Direct the driver or other convoy personnel to notify the nearest fire and police departments, using the most expeditious means; for example, roadside emergency, service station, or private residence telephone. If radio communication is available, notify the convoy commander.
  • Remove injured personnel from burning vehicles as quickly as possible, even when it means subjecting a person to further injury. Follow established first aid procedures in caring for the injured before attempting to control fire in unoccupied vehicles.
  • Keep spectators at a safe distance.
  • Attempt to extinguish the fire with the control vehicle extinguisher, extinguishers from other vehicles, or with sand or mud.

Vehicle Accidents Involving a Truck Carrying Explosives or Hazardous Cargo. In the event of an accident involving a truck carrying either explosives or hazardous cargo, supervisory personnel are instructed to take the following actions:

  • Approach cautiously. Resist the urge to rush in; people involved in the accident cannot be helped or rescued until the hazards are known.
  • Use the Emergency Response Guidebook as a guide.
  • Immediately notify all assisting agencies and personnel of the hazards involved.
  • If the accident results in a fire hazard, supervisory personnel should:
    • Halt the control vehicle a safe distance from the accident. Direct the driver or other convoy personnel to notify police and fire departments by the fastest means. When radio communication is available, notify the convoy commander.
    • Turn off the ignition and lights of the vehicles involved. Because of the possibility of sparks, do not remove battery cables unless absolutely necessary.
    • Remove injured personnel as soon as possible.
    • Keep spectators away from areas where flammable liquids have been spilled or toxic fumes have accumulated.
    • Guard against smoking by spectators or cigarettes thrown from passing vehicles. If personnel are available, post guards to warn passing drivers of a fire hazard.
    • Notify nearby residents when spillage may place them in danger.

Vehicle Accidents Involving Power Lines. If the accident involves high-tension power lines, an extremely dangerous situation exists. The danger is even greater when the downed lines are touching a vehicle. Convoy supervisory personnel will take the following steps:

  • Contact police immediately and explain the situation. The police will be able to contact power company personnel for emergency assistance more quickly than convoy personnel.
  • Keep spectators at least 100 feet from downed wires.
  • If wires are touching any of the vehicles involved, direct the occupants to remain in place until power company workers can cut off the electricity and remove the wires.
  • In case of serious injury where death may be imminent unless rescue is effected, attempt to remove the wires, assist the injured from the vehicle, render first aid, and obtain medical assistance.
  • The following procedures are NOT routine. Perform the following only when death may result:
    • Remove the wires from the vehicle by looping a completely dry fiber or cotton rope around them and pulling them free.
    • Lift the wires from the vehicle using a completely dry-seasoned wooden pole.

    Reduce the risk of electrical shock by standing on a rubber vehicle floor mat, dry wooden planking, or other nonconductive material. Rescue personnel must be aware that the ground close to an area touched by a hot wire may be charged and should be avoided.

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