US Army Dictionary of Military Terms

rear echelon — (*) Elements of a force which are not required in the objective area.

rear guard — 1. The rearmost elements of an advancing or a withdrawing force. It has the following functions: to protect the rear of a column from hostile forces; during the withdrawal, to delay the enemy; during the advance, to keep supply routes open. 2. Security detachment that a moving ground force details to the rear to keep it informed and covered. See also guard.

rearming — 1. An operation that replenishes the prescribed stores of ammunition, bombs, and other armament items for an aircraft, naval ship, tank, or armored vehicle (including replacement of defective ordnance equipment) in order to make it ready for combat service. 2. Resetting the fuze on a bomb or on an artillery, mortar, or rocket projectile so that it will detonate at the desired time.

reattack recommendation — An assessment, derived from the results of battle damage assessment and munitions effectiveness assessment, providing the commander systematic advice on reattack of targets and further target selection to achieve objectives. The reattack recommendation considers objective achievement, target, and aimpoint selection, attack timing, tactics, and weapon system and munitions selection. The reattack recommendation is a combined operations and intelligence function. Also called RR.

See also assessment; battle damage assessment; munitions effectiveness assessment; target. (JP 3-60)

rebuild — The restoration of an item to a standard as nearly as possible to its original condition in appearance, performance, and life expectancy. See also overhaul; repair.

receipt — Atransmission made by a receiving station to indicate that a message has been satisfactorily received.

receipt into the supply system — That point in time when the first item or first quantity of the item of the contract has been received at or is en route to point of first delivery after inspection and acceptance. See also procurement lead time.

receiving ship — The ship in a replenishment unit that receives the rig(s).

reception — 1. All ground arrangements connected with the delivery and disposition of air or sea drops. Includes selection and preparation of site, signals for warning and approach, facilitation of secure departure of agents, speedy collection of delivered articles, and their prompt removal to storage places having maximum security. When a group is involved, it may be called a reception committee. 2. Arrangements to welcome and provide secure quarters or transportation for defectors, escapees, evaders, or incoming agents. 3. The process of receiving, offloading, marshalling, and transporting of personnel, equipment, and materiel from the strategic and/or intratheater deployment phase to a sea, air, or surface transportation point of debarkation to the marshalling area. (JP 4-01.8)

receptivity — (*) The vulnerability of a target audience to particular psychological operations media.

reclama — A request to duly constituted authority to reconsider its decision or its proposed action.

recognition — 1. The determination by any means of the individuality of persons, or of

objects such as aircraft, ships, or tanks, or of phenomena such as communicationselectronics patterns. 2. In ground combat operations, the determination that an object is similar within a category of something already known; e.g., tank, truck, man.

recognition signal — Any prearranged signal by which individuals or units may identify each other.

recompression chamber — See hyperbaric chamber.

reconnaissance — (*) A mission undertaken to obtain, by visual observation or other detection methods, information about the activities and resources of an enemy or potential enemy, or to secure data concerning the meteorological, hydrographic, or geographic characteristics of a particular area. Also called RECON.

reconnaissance by fire — (*) A method of reconnaissance in which fire is placed on a suspected enemy position to cause the enemy to disclose a presence by movement or return of fire.

reconnaissance exploitation report — (*)

A standard message format used to report the results of a tactical air reconnaissance mission. Whenever possible the report should include the interpretation of sensor imagery. Also called RECCEXREP.

reconnaissance in force — (*) An offensive operation designed to discover and/or test the enemy’s strength or to obtain other information.

reconnaissance patrol — See patrol.

reconnaissance photography —

Photography taken to obtain information on the results of bombing, or on enemy movements, concentrations, activities, and

forces. The primary purposes do not include making maps, charts, or mosaics.

reconstitution site — A location selected by the surviving command authority as the site at which a damaged or destroyed headquarters can be reformed from survivors of the attack and/or personnel from other sources, predesignated as replacements.

record information — All forms (e.g., narrative, graphic, data, computer memory) of information registered in either temporary or permanent form so that it can be retrieved, reproduced, or preserved.

recoverable item — An item that normally is not consumed in use and is subject to return for repair or disposal. See also reparable item.

recovery — 1. In air (aviation) operations, that phase of a mission which involves the return of an aircraft to a land base or platform afloat. 2. The retrieval of a mine from the location where emplaced. 3. Actions taken to rescue or extract personnel for return to friendly control. 4. Actions taken to extricate damaged or disabled equipment for return to friendly control or repair at another location. See also evader; evasion; evasion and recovery; recovery; recovery force.

recovery activation signal — In evasion and recovery operations, a precoordinated signal from an evader that indicates his or her presence in an area to a receiving or observing source that indicates “I am here, start the recovery planning.” Also called

RAS. See also evader; evasion; evasion and recovery; recovery operations; signal. (JP 3-50.3)

recovery airfield — Any airfield, military or civil, at which aircraft might land

post-H-hour. It is not expected that combat missions would be conducted from a recovery airfield. See also airfield.

recovery and reconstitution — 1. Those actions taken by one nation prior to, during, and following an attack by an enemy nation to minimize the effects of the attack, rehabilitate the national economy, provide for the welfare of the populace, and maximize the combat potential of remaining forces and supporting activities. 2. Those actions taken by a military force during or after operational employment to restore its combat capability to full operational readiness. See also recovery. (JP 3-35)

recovery force — In evasion and recovery operations, an organization consisting of personnel and equipment with a mission of seeking out evaders, contacting them, and returning them to friendly control. See also evader; evasion; evasion and recovery; recovery operations. (JP 3-50.3)

recovery operations — Operations conducted to search for, locate, identify, rescue, and return personnel, sensitive equipment, or items critical to national security. (JP 3-07)

recovery procedures — See explosive ordnance disposal procedures.

recovery site — In evasion and escape usage, an area from which an evader or an escapee can be evacuated. See also escapee; evader; evasion; evasion and escape.

(JP 3-50.3)

recovery vehicle — In combat search and rescue, the vehicle (aircraft, maritime, or land), on which isolated personnel are boarded and transported from the pickup site.

recovery zone — A designated geographic area from which special operations forces can be extracted by air, boat, or other means. Also called RZ. (JP 3-05.5)

rectification — (*) In photogrammetry, the process of projecting a tilted or oblique photograph on to a horizontal reference plane.

recuperation — Not to be used. See recovery and reconstitution.

recurring demand — A request by an authorized requisitioner to satisfy a materiel requirement for consumption or stock replenishment that is anticipated to recur periodically. Demands for which the probability of future occurrence is unknown will be considered as recurring. Recurring demands will be considered by the supporting supply system in order to procure, store, and distribute materiel to meet similar demands in the future.

redeployment — The transfer of forces and materiel to support another joint force commander’s operational requirements, or to return personnel, equipment, and materiel to the home and/or demobilization stations for reintegration and/or out-processing. See also deployment. (JP 3-35)

redeployment airfield — (*) An airfield not occupied in its entirety in peacetime, but available immediately upon outbreak of war for use and occupation by units redeployed from their peacetime locations. It must have substantially the same standard of operational facilities as the main airfield. See also airfield; departure airfield; diversion airfield; main airfield.

RED HORSE — Air Force units wartimestructured to provide a heavy engineer capability. They have a responsibility

across the operational area, are not tied to a specific base, and are not responsible for base operation and maintenance. These units are mobile, rapidly deployable, and largely self-sufficient for limited periods of time. (JP 3-34)

redistribution — The act of effecting transfer in control, utilization, or location of materiel between units or activities within or among the Military Services or between the Military Services and other Federal agencies.

reduced charge — 1. The smaller of the two propelling charges available for naval guns. 2. Charge employing a reduced amount of propellant to fire a gun at short ranges as compared to a normal charge. See also normal charge.

reduced lighting — (*) The reduction in brightness of ground vehicle lights by either reducing power or by screening in such a way that any visible light is limited in output. See also normal lighting.

reduced operational status — Applies to the Military Sealift Command ships withdrawn from full operational status (FOS) because of decreased operational requirements. A ship in reduced operational status is crewed in accordance with shipboard maintenance and possible future operational requirements, with crew size predetermined contractually. The condition of readiness in terms of calendar days required to attain FOS is designated by the numeral following the acronym ROS (i.e., ROS-5). Also called

ROS. See also Military Sealift Command. (JP 3-02.2)

reduction — The creation of lanes through a minefield or obstacle to allow passage of the attacking ground force. (JP 3-15)

reduction (photographic) — The production of a negative, diapositive, or print at a scale smaller than the original.

reefer — 1. A refrigerator. 2. A motor vehicle, railroad freight car, ship, aircraft, or other conveyance, so constructed and insulated as to protect commodities from either heat or cold.

reentry phase — That portion of the trajectory of a ballistic missile or space vehicle where there is a significant interaction of the vehicle and the Earth’s atmosphere. See also boost phase; midcourse phase; terminal phase.

reentry vehicle — (*) That part of a space vehicle designed to re-enter the Earth’s atmosphere in the terminal portion of its trajectory. Also called RV. See also maneuverable reentry vehicle; multiple reentry vehicle.

reference datum — As used in the loading of aircraft, an imaginary vertical plane at or near the nose of the aircraft from which all horizontal distances are measured for balance purposes. Diagrams of each aircraft show this reference datum as “balance station zero.”

reference diversion point — (*) One of a number of positions selected by the routing authority on both sides of the route of a convoy or independent to facilitate diversion at sea.

reference point — (*) A prominent, easily located point in the terrain.

reflected shock wave — When a shock wave traveling in a medium strikes the interface between this medium and a denser medium, part of the energy of the shock wave induces

a shock wave in the denser medium and the remainder of the energy results in the formation of a reflected shock wave that travels back through the less dense medium.

reflex sight — (*) An optical or computing sight that reflects a reticle image (or images) onto a combining glass for superimposition on the target.

refraction — The process by which the direction of a wave is changed when moving into shallow water at an angle to the bathymetric contours. The crest of the wave advancing in shallower water moves more slowly than the crest still advancing in deeper water, causing the wave crest to bend toward alignment with the underwater contours. (JP 4-01.6)

refuge area — (*) A coastal area considered safe from enemy attack to which merchant ships may be ordered to proceed when the shipping movement policy is implemented. See also safe anchorage.

refugee — A person who, by reason of real or imagined danger, has left their home country or country of their nationality and is unwilling or unable to return. See also dislocated civilian; displaced person; evacuee; expellee; stateless person.

(JP 3-07.6)

regimental landing team — A task organization for landing comprised of an infantry regiment reinforced by those elements that are required for initiation of its combat function ashore.

regional satellite communications support center — United States Space Command operational element responsible for providing the operational communications planners with a single all-spectrum (extremely high frequency, super-high frequency, ultrahigh frequency, Ku, and Ka) point of contact for accessing and

managing satellite communications (SATCOM) resources. Specific tasks include: supporting combatant commanders’ (CINCs’) deliberate and crisis planning, assisting CINCs in day-to- day management of apportioned resources and allocating non-apportioned resources, assisting theater spectrum managers, and facilitating SATCOM interface to the defense information infrastructure. Also called RSSC.

register — (*) In cartography, the correct position of one component of a composite map image in relation to the other components, at each stage of production.

registration — The adjustment of fire to determine firing data corrections.

registration fire — (*) Fire delivered to obtain accurate data for subsequent effective engagement of targets. See also fire.

registration point — (*) Terrain feature or other designated point on which fire is adjusted for the purpose of obtaining corrections to firing data.

regrade — To determine that certain classified information requires, in the interests of national defense, a higher or a lower degree of protection against unauthorized disclosure than currently provided, coupled with a changing of the classification designation to reflect such higher or lower degree.

regular drill — See unit training assembly.

regulated item — (*) Any item whose issue to a user is subject to control by an appropriate authority for reasons that may include cost, scarcity, technical or hazardous nature, or operational significance. Also called controlled item.

See also critical supplies and materiel.

regulating point — An anchorage, port, or ocean area to which assault and assault follow-on echelons and follow-up shipping proceed on a schedule, and at which they are normally controlled by the commander, amphibious task force, until needed in the transport area for unloading. See also assault; commander, amphibious task force. (JP 3-02)

regulating station — A command agency established to control all movements of personnel and supplies into or out of a given area.

rehabilitation — (*) 1. The processing, usually in a relatively quiet area, of units or individuals recently withdrawn from combat or arduous duty, during which units recondition equipment and are rested, furnished special facilities, filled up with replacements, issued replacement supplies and equipment, given training, and generally made ready for employment in future operations. 2. The action performed in restoring an installation to authorized design standards.

rehearsal phase — In amphibious operations, the period during which the prospective operation is practiced for the purpose of:

(1) testing adequacy of plans, the timing of detailed operations, and the combat readiness of participating forces; (2) ensuring that all echelons are familiar with plans; and (3) testing communicationsinformation systems. See also amphibious operation. (JP 3-02)

reinforcement training unit — See voluntary training unit.

reinforcing — A support mission in which the supporting unit assists the supported unit to accomplish the supported unit’s mission. Only like units (e.g., artillery to artillery, intelligence to intelligence, armor to armor,

etc) can be given a reinforcing/reinforced mission.

reinforcing obstacles — Those obstacles specifically constructed, emplaced, or detonated through military effort and designed to strengthen existing terrain to disrupt, fix, turn, or block enemy movement. See also obstacle. (JP 3-15)

relateral tell — (*) The relay of information between facilities through the use of a third facility. This type of telling is appropriate between automated facilities in a degraded communications environment. See also track telling.

relative altitude — See vertical separation.

relative bearing — (*) The direction expressed as a horizontal angle normally measured clockwise from the forward point of the longitudinal axis of a vehicle, aircraft, or ship to an object or body. See also bearing; grid bearing.

relative biological effectiveness — The ratio of the number of rads of gamma (or X) radiation of a certain energy that will produce a specified biological effect to the number of rads of another radiation required to produce the same effect measures the “relative biological effectiveness” of the latter radiation.

release — (*) In air armament, the intentional separation of a free-fall aircraft store, from its suspension equipment, for purposes of employment of the store.

release altitude — Altitude of an aircraft above the ground at the time of release of bombs, rockets, missiles, tow targets, etc.

release point (road) — A well-defined point on a route at which the elements composing a column return under the authority of their

respective commanders, each one of these elements continuing its movement towards its own appropriate destination.

releasing commander (nuclear weapons)

— A commander who has been delegated authority to approve the use of nuclear weapons within prescribed limits. See also executing commander (nuclear weapons).

releasing officer — A properly designated individual who may authorize the sending of a message for and in the name of the originator. See also originator.

reliability diagram — (*) In cartography, a diagram showing the dates and quality of the source material from which a map or chart has been compiled. See also information box.

reliability of source — See evaluation.

relief — (*) Inequalities of evaluation and the configuration of land features on the surface of the Earth which may be represented on maps or charts by contours, hypsometric tints, shading, or spot elevations.

relief in place — (*) An operation in which, by direction of higher authority, all or part of a unit is replaced in an area by the incoming unit. The responsibilities of the replaced elements for the mission and the assigned zone of operations are transferred to the incoming unit. The incoming unit continues the operation as ordered.

religious ministry support — The entire spectrum of professional duties, to include providing for or facilitating essential religious needs and practices; pastoral care; family support programs; religious education; volunteer and community activities; and programs performed to enhance morale and moral, ethical, and

personal well being. Enlisted religious support personnel assist the chaplain in providing religious ministry support. See also command chaplain; command chaplain of the combatant command; lay leader or lay reader; religious ministry support plan; religious ministry support team; Service component command chaplain. (JP 1-05)

religious ministry support plan — A plan that describes the way in which religious support personnel will provide religious support to all members of a joint force. When approved by the commander, it may be included as an annex to operation plans. See also command chaplain; command chaplain of the combatant command; lay leader or lay reader; religious ministry support; religious ministry support team; Service component command chaplain. (JP 1-05)

religious ministry support team — A team that is composed of a chaplain and an Army chaplain assistant, Navy religious program specialist, Air Force chaplain service support personnel, and/or Coast Guard yeoman. The team works together in designing, implementing, and executing the command religious program. See also command chaplain; command chaplain of the combatant command; lay leader or lay reader; religious ministry support; religious ministry support plan; Service component command chaplain. (JP 1-05)

relocatable building — A building designed to be readily moved, erected, disassembled, stored, and reused. All types of buildings or building forms designed to provide relocatable capabilities are included in this definition. In classifying buildings as relocatable, the estimated funded and unfunded costs for average building disassembly, repackaging (including normal repair and refurbishment of components), and nonrecoverable building

components, including typical foundations, may not exceed 20 percent of the building acquisition cost. Excluded from this definition are building types and forms that are provided as an integral part of a mobile equipment item and that are incidental portions of such equipment components, such as communications vans or trailers. (JP 4-04)

remain-behind equipment — Unit equipment left by deploying forces at their bases when they deploy. (JP 3-02.2)

remaining forces — The total surviving United States forces at any given stage of combat operations.

remote delivery — (*) In mine warfare, the delivery of mines to a target area by any means other than direct emplacement. The exact position of mines so laid may not be known.

remotely piloted vehicle — (*) An unmanned vehicle capable of being controlled from a distant location through a communication link. It is normally designed to be recoverable. See also drone.

render safe procedures — See explosive ordnance disposal procedures.

rendezvous area — In an amphibious operation, the area in which the landing craft and amphibious vehicles rendezvous to form waves after being loaded, and prior to movement to the line of departure.

reorder cycle — The interval between successive reorder (procurement) actions.

reorder point — 1. That point at which time a stock replenishment requisition would be submitted to maintain the predetermined or calculated stockage objective. 2. The sum of the safety level of supply plus the level

for order and shipping time equals the reorder point. See also level of supply.

repair — The restoration of an item to serviceable condition through correction of a specific failure or unserviceable condition. See also overhaul; rebuild.

repair and restoration — Repair, beyond emergency repair, of war-damaged facilities to restore operational capability in accordance with combatant command standards of construction, including repair and restoration of pavement surfaces. Normally, repairs to facilities will be made using materials similar to those of the original construction. For severely damaged facilities (i.e., essentially destroyed), restoration may require reconstruction. (JP 4-04)

repair cycle — The stages through which a reparable item passes from the time of its removal or replacement until it is reinstalled or placed in stock in a serviceable condition.

repair cycle aircraft — Aircraft in the active inventory that are in or awaiting depot maintenance, including those in transit to or from depot maintenance.

reparable item — An item that can be reconditioned or economically repaired for reuse when it becomes unserviceable. See also recoverable item.

repatriate — A person who returns to his or her country or citizenship, having left said native country either against his or her will, or as one of a group who left for reason of politics, religion, or other pertinent reasons.

repatriation — 1. The procedure whereby American citizens and their families are officially processed back into the United States subsequent to an evacuation. See also evacuation. 2. The release and return of enemy prisoners of war to their own

country in accordance with the 1949 Geneva Convention Relative to the Treatment of Prisoners of War. (JP 1-0)

repeater-jammer — (*) A receiver transmitter device which amplifies, multiplies, and retransmits the signals received, for purposes of deception or jamming.

replacement demand — A demand representing replacement of items consumed or worn out.

replacement factor — (*) The estimated percentage of equipment or repair parts in use that will require replacement during a given period due to wearing out beyond repair, enemy action, abandonment, pilferage, and other causes except catastrophes.

replacements — Personnel required to take the place of others who depart a unit.

replenishment at sea — (*) Those operations required to make a transfer of personnel and/or supplies when at sea.

reported unit — A unit designation that has been mentioned in an agent report, captured document, or interrogation report, but for which available information is insufficient to include the unit in accepted order of battle holdings.

reporting post — (*) An element of the control and reporting system used to extend the radar coverage of the control and reporting center. It does not undertake the control of aircraft.

reporting time interval — 1. In surveillance, the time interval between the detection of an event and the receipt of a report by the user. 2. In communications, the time for transmission of data or a report from the

originating terminal to the end receiver. See also near real time.

representative downwind direction — (*)

During the forecast period, the mean surface downwind direction in the hazard area towards which the cloud travels.

representative downwind speed — (*) The mean surface downwind speed in the hazard area during the forecast period.

representative fraction — The scale of a map, chart, or photograph expressed as a fraction or ratio. See also scale.

request for information — 1. Any specific time-sensitive ad hoc requirement for intelligence information or products to support an ongoing crisis or operation not necessarily related to standing requirements or scheduled intelligence production. A request for information can be initiated to respond to operational requirements and will be validated in accordance with the theater command’s procedures. 2. The National Security Agency/Central Security Service uses this term to state ad hoc signals intelligence requirements. Also called RFI. See also information; intelligence. (JP 2-01)

request modify — (*) In artillery and naval gunfire support, a request by any person, other than the person authorized to make modifications to a fire plan, for a modification.

required delivery date — The date that a force must arrive at the destination and complete unloading. Also called RDD.

required supply rate (ammunition) — The amount of ammunition expressed in terms of rounds per weapon per day for ammunition items fired by weapons (and in terms of other units of measure per day for bulk allotment and other items)

estimated to be required to sustain operations of any designated force without restriction for a specified period. Tactical commanders use this rate to state their requirements for ammunition to support planned tactical operations at specified intervals. The required supply rate is submitted through command channels. It is consolidated at each echelon and is considered by each commander in subsequently determining the controlled supply rate within the command. Also called RSR. See also ammunition controlled supply rate.

requirements — See military requirement.

requirements capability — This capability provides a Joint Operation Planning and Execution System user with the ability to identify, update, review, and delete data on forces and sustainment required to support an operation plan or course of action.

requirements management system — A system for the management of theater and national imagery collection requirements that provides automated tools for users in support of submission, review, and validation of imagery nominations as requirements to be tasked on national or Department of Defense imagery collection, production, and exploitation resources. Also called RMS. See also imagery. (JP 2-01)

requisition — (*) 1. An authoritative demand or request especially for personnel, supplies, or services authorized but not made available without specific request. 2. (DOD only) To demand or require services from an invaded or conquered nation.

requisitioning objective — The maximum quantities of materiel to be maintained on hand and on order to sustain current operations. It will consist of the sum of

stocks represented by the operating level, safety level, and the order and shipping time or procurement lead time, as appropriate. See also level of supply.

rescue combat air patrol — An aircraft patrol provided over a combat search and rescue objective area for the purpose of intercepting and destroying hostile aircraft. Its primary mission is to protect the search and rescue task forces during recovery operations. Also called RESCAP. See also combat air patrol.

rescue coordination center — A primary search and rescue facility suitably staffed by supervisory personnel and equipped for coordinating and controlling search and rescue and/or combat search and rescue operations. The facility is operated unilaterally by personnel of a single Service or component. For Navy component operations, this facility may be called a rescue coordination team. Also called RCC (or RCT for Navy component). See also combat search and rescue; joint search and rescue center; search and rescue.

(JP 3-50.2)

rescue ship — (*) In shipping control, a ship of a convoy stationed at the rear of a convoy column to rescue survivors.

research — All effort directed toward increased knowledge of natural phenomena and environment and toward the solution of problems in all fields of science. This includes basic and applied research.

reseau — (*) A grid system of a standard size in the image plane of a photographic system used for mensuration purposes.

reservation — The stated qualification by a nation that describes the part of a standardization agreement that it will not implement or will implement only with