FM 101-5-1
Operational Terms and Graphics

Chapter 1


identification, friend or foe (IFF) (JP 1-02, NATO) - A system using electromagnetic transmissions to which equipment carried by friendly forces automatically responds, for example, by emitting pulses, thereby distinguishing themselves from enemy forces. (Army) - A device which emits a signal positively identifying it as a friendly. (See also air defense.) See FMs 1-111, 44-100, and 100-103.

identification, friend or foe (IFF) on/off line (Army) - A theater-directed phase line where aircraft involved in deep operations forward of the fire support coordination line turn off the aircraft IFF transponder en route to the target and turn on the transponder after completing the mission. (See also identification, friend or foe (IFF), and phase line (PL).) See FM 100-103.

imagery intelligence (IMINT) (JP 1-02) - Intelligence derived from the exploitation of collection by visual photography, infrared sensors, lasers, electro-optics, and radar sensors, such as synthetic aperture radar wherein images of objects are reproduced optically or electronically on film, electronic display devices, or other media. (See also intelligence.) See FMs 34-1, 34-3, and 34-10.

imitative electromagnetic deception (IED) (JP 1-02) - The introduction of electromagnetic energy into enemy systems that imitates enemy emissions. (Army) - Imitating enemy electromagnetic radiation (predominately communications) after intruding his electromagnetic channels to deceive him or to disrupt his operations. (See also command and control warfare (C2W), deception, electronic warfare (EW), manipulative electromagnetic deception (MED), and simulative electromagnetic deception.) See FMs 34-1, 34-10, 34-40, 90-2, and 100-6.

immediate air support (JP 1-02, NATO) - Air support to meet specific requests which arise during the course of a battle and which by their nature cannot be planned in advance. (See also air support.) See FM 6-series.

immediate decontamination (JP 1-02, NATO) - Decontamination carried out by individuals upon becoming contaminated, to save life and minimize casualties. This may include decontamination of some personal clothing and/or equipment. (See also decontamination.) See FM 3-5.

immediate mission request (JP 1-02) - A request for an air strike on a target which by its nature could not be identified sufficiently in advance to permit detailed mission coordination and planning. (NATO: a request for immediate air support.)

immediate permanent ineffectiveness, 8,000 cGy - The physiological response to radiation at levels of 3,000 cGy for physically demanding tasks or 3,800 cGy for physically undemanding tasks. Personnel become ineffective within three minutes of exposure and remain ineffective until death. Death occurs within one day. See FM 3-3-1.

immediate transient ineffectiveness (nuclear) - The physiological response to radiation at levels of 2,000 cGy for physically demanding tasks or 2,800 cGy for physically undemanding tasks. Personnel irradiated by a nuclear explosion or accident become ineffective for any task within 3 minutes of exposure and remain so for approximately 7 minutes, independent of the physical demands of the task. Personnel recover to greater than 75 percent of their pre-exposure performance levels at around 10 minutes postexposure and remain so for around 30 minutes. At around 40 minutes postexposure, personnel become performance- degraded and remain so for around five hours for undemanding tasks (two hours for demanding tasks), at which time it is expected that radiation sickness symptoms will be present in sufficient severity to render the personnel ineffective. The personnel will remain ineffective until death occurs in five to six days. See FM 3-3-1 and JPs 3-12.2 and 3-12.3.

implementation force (IFOR) - A task-organized military command which is to execute and enforce an international treaty or agreement. This command performs the missions and tasks as defined in the treaty or agreement. The missions and tasks may include peace operations, nation building, peace enforcement, and humanitarian assistance. (See also peace operations and stability and support operations (SASO).) See FM 100-23.

incapacitating agent (JP 1-02) - An agent that produces temporary physiological or mental effects, or both, that will render individuals incapable of concerted effort in performing their duties. See FM 3-9 and FM 3-100.

incendiary - A compound that generates sufficient heat to cause the target to catch fire or causes melting or burning of equipment. See FM 3-9.

in-depth defense - A choice of defensive maneuver that forces the enemy to attack through a series of mutually supporting friendly positions, causing the enemy's mass to be expended and his supporting forces to be unable to focus. This choice of maneuver reduces the risk of an enemy penetration and allows the enemy to gain terrain to wear him down and overextend his ability to sustain his attack. In-depth defense usually culminates in a friendly counterattack to complete the destruction of the enemy and regain lost terrain. (See also choices of maneuver and defensive operations.)

indirect approach (Army) - To attack an enemy at his weakness to cause his strength to be ineffective, ultimately resulting in his defeat.

indirect fire (JP 1-02) - Fire delivered on a target that is not itself used as a point of aim for the weapons or the director. (Army) - Fire delivered on a target characterized by a relatively high trajectory and where the weapon operator normally does not have visual contact with the target. (See also direct laying.) See FMs 6-20 series and 7-90.

indirect illumination (JP 1-02, NATO) - Battlefield illumination provided by employing searchlight or pyrotechnic illuminants using diffusion or reflection. a. Illumination by diffusion: Illumination of an area beneath and to the flanks of a slightly elevated searchlight or of pyrotechnic illuminants, by the light scattered from atmospheric particles. b. Illumination by reflection: Illumination of an area by reflecting light from low cloud. Either or both of these effects are present when a searchlight is used in defilade or with its beam spread to maximum width.

individual protection - 1. Actions taken by individual soldiers to survive and continue the mission under nuclear, biological, chemical (NBC) conditions. See FM 3-100 2. Actions taken by individual soldiers to protect themselves from the effects of direct and indirect fire. See FMs 5-103, 7-7, and 7-8.

induced radiation (JP 1-02, NATO) - Radiation produced as a result of exposure to radioactive materials, particularly the capture neutrons. See FM 3-3-1.

in extremis (JP 1-02) - A situation of such exceptional urgency that immediate action must be taken to minimize imminent loss of life or catastrophic degradation of the political or military situation. See FM 100-20.

infiltration (JP 1-02) - 1. The movement through or into an area or territory occupied by either friendly or enemy troops or organizations. The movement is made, either by small groups or by individuals, at extended or irregular intervals. When used in connection with the enemy, it infers that contact is avoided. 2. In intelligence usage, placing an agent or other person in a target area in hostile territory. Usually involves crossing a frontier or other guarded line. Methods of infiltration are: black (clandestine); grey (through legal crossing point but under false documentation); white (legal). (Army) - 1. A choice of maneuver that entails movement through or into an area occupied by an enemy or a friendly force by small groups or individuals at extended or irregular intervals in which contact with the enemy is avoided. 2. When used in conjunction with a tactical vehicular march, vehicles are dispatched individually or in small groups at irregular intervals to reduce density and prevent undue massing of vehicles. (See also choices of maneuver and exfiltration.) See FMs 7-7, 7-8, 7-10, 7-20, 7-30, 17-95, 31-20, 34-1, 71-100, 71-123, 100-5, and 100-15.

inflight report (JP 1-02) - The transmission from the airborne system of information obtained both at the target and en route.

informant (JP 1-02) - 1. A person who, wittingly or unwittingly, provides information to an agent, a clandestine service, or the police. 2. In reporting, a person who has provided specific information and is cited as a source. (See also human intelligence (HUMINT), military operations other than war (MOOTW), and support and stability operations (SASO).) See FMs 34-1 and 100-20.

information (JP 1-02, NATO) - 1. Unprocessed data of every description which may be used in the production of intelligence. (DOD) 2. The meaning that a human assigns to data by means of the known conventions used in their representation. See FMs 34-1 and 100-6.

information dominance (Army) - The degree of information superiority that allows the possessor to use information systems and capabilities to achieve an operational advantage in a conflict or to control the situation in operations other than war, while denying those capabilities to the adversary. See FM 100-6.

information operations (IO) - Continuous military operations within the military information environment that enable, enhance, and protect the friendly force's ability to collect, process, and act on information to achieve an advantage across the full range of military operations. Information operations include interacting with the global information environment and exploiting or denying an adversary's information and decision capabilities. See FM 100-6.

information requirements (IR) (JP 1-02, NATO) - Those items of information regarding the enemy and his environment which need to be collected and processed in order to meet the intelligence requirements of a commander. (See also commander's critical information requirements (CCIR) and priority intelligence requirements (PIR).) See FMs 34-1, 34-10, 34-130, and 101-5.

information systems (Army) - The entire infrastructure, organization, personnel, and components that collect, process, store, transmit, display, disseminate, and act on information. See FM 100-6.

information systems security (ISS) - The protection of information systems against unauthorized access to or modification of information, whether in storage, processing, or transit, and against denial of service to authorized users or the providing of access to unauthorized users, including those measures necessary to detect, document, and counter such threats. See FM 100-6.

information warfare (IW) - Actions taken to achieve information superiority by affecting a hostileÁs information, information-based processes, and information systems, while defending oneÁs own information, information-based processes, and information systems. See FM 100-6.

infosphere (Army) - The rapidly growing global network of military and commercial command, control, communications, and computer systems and networks linking information databases and fusion centers that are accessible to the warrior anywhere, anytime, and during the performance of any mission. The infosphere provides the worldwide automated information exchange backbone that provides support to forces and provides seamless operations from anywhere to anywhere. The network of databases and fusion centers is secure, and its complexity is transparent to the warrior user. This emerging capability is highly flexible and can support the adaptive command and control infrastructures of the twenty-first century. See FM 100-6.

infrastructure (JP 1-02, NATO) - A term generally applicable to all fixed and permanent installations, fabrications, or facilities for the support and control of military forces. (Army) - 1. The basic, underlying framework or features of a thing. 2. In economics, basic resources, communications, industries, and so forth, upon which others depend. 3. In insurgency, the organization (usually hidden) of insurgent leadership. See FMs 100-5 and 100-20.

initial nuclear effects - Effects that occur within the first minute and includes initial nuclear radiation, blast, thermal, and electromagnetic pulse. See FMs 3-3-1, 100-30, JPs 3-12.2, and 3-12.3.

initial point (IP) (JP 1-02) - 1. The first point at which a moving target is located on a plotting board. 2. A well-defined point, easily distinguishable visually and/or electronically, used as a starting point for the bomb run to the target. See FM 6-20 series. 3. Airborne-a point close to the landing area where serials (troop carrier air formations) make final alterations in course to pass over individual drop or landing zones. See FMs 7-7, 7-10, 7-20, 7-30, 71-100-2, and 90-26. 4. Helicopter-an air control point in the vicinity of the landing zone from which individual flights of helicopters are directed to their prescribed landing sites. 5. Any designated place at which a column or element thereof is formed by the successive arrival of its various subdivisions, and comes under the control of the commander ordering the move. See FMs 1-111 and 100-103.

initial response force (JP 1-02) - The first unit, usually military police, on the scene of a terrorist incident. (See also antiterrorism (AT).) See FM 19-1.

initiative (Army) - The ability to set or change the terms of battle; implies an offensive spirit.

injury (JP 1-02) - A term comprising such conditions as fractures, wounds, sprains, strains, dislocations, concussions, and compressions. In addition, it includes conditions resulting from extremes of temperature or prolonged exposure. Acute poisonings, except those due to contaminated food, resulting from exposure to a toxic or poisonous substance are also classed as injuries.

insertion (Army) - 1. Placement of troops and equipment into an operational area in air assault operations. 2. The placement of observation posts, patrols, or raiding parties either by helicopter or parachute. (See also air assault.) See FMs 1-111, 71-100-3, and 90-4.

in-stride breach - A type of breaching used by maneuver units to quickly overcome unexpected or lightly defended tactical obstacles. Maneuver battalions and companies are task-organized with the assets necessary to conduct independent breaching operations. These include mine rollers, mine plows, engineers, priority of artillery, mortars, close air support, air defense, smoke targets, and smoke generators. (See also breach and deliberate breach.) See FM 90-13-1.

insurgency (JP 1-02, NATO) - An organized movement aimed at the overthrow of a constituted government through the use of subversion and armed conflict. (See also counterinsurgency.) See FMs 90-8 and 100-20.

integrated combat airspace command and control (ICAC2) - A system capable of linking and coordinating the airspace use and restrictions of all Services and a host nation, which may include aircraft, air defense, rocket artillery, unmanned aerial vehicles, and other high trajectory weapon systems, in order to maximize the accommodation of mission requirements. (See also Army airspace command and control (A2C2).) See FM 100-103-1.

integrated warfare (JP 1-02) - The conduct of military operations in any combat environment wherein opposing forces employ nonconventional weapons in combination with conventional weapons. See FM 3-100.

intelligence (JP 1-02) - 1. The product resulting from the collection, processing, integration, analysis, evaluation, and interpretation of available information concerning foreign countries or areas. 2. Information and knowledge about an adversary obtained through observation, investigation, analysis, or understanding. (See also combat intelligence and imagery intelligence (IMINT).) See FMs 34-1, 34-10, and 34-40.

intelligence collection plan (JP 1-02) - A plan for gathering information from all available sources to meet an intelligence requirement. Specifically, a logical plan for transforming the essential elements of information into orders or requests to sources within a required time limit. (See also commander's critical information requirements (CCIR), intelligence cycle, and reconnaissance and surveillance (R&S) plan.) See FMs 34-1, 34-10, and 101-5.

intelligence cycle (JP 1-02) - The steps by which information is converted into intelligence and made available to users. There are five steps in the cycle: a. planning and direction - Determination of intelligence requirements, preparation of a collection plan, issuance of orders and requests to inormation collection agencies, and a continuous check on the productivity of collection agencies. b. collection - Acquisition of information and the provision of this information to processing and/or production elements. c. processing - Conversion of collected information into a form suitable to the production of intelligence. d. production - Conversion of information into intelligence through the integration, analysis, evaluation, and interpretation of all source data and the preparation of intelligence products in support of known or anticipated user requirements. e. dissemination - Conveyance of intelligence to users in a suitable form. (See also intelligence and intelligence collection plan.) See FM 34-1.

intelligence preparation of the battlefield (IPB) - A systematic approach to analyzing the enemy, weather, and terrain in a specific geographic area. It integrates enemy doctrine with the weather and terrain as they relate to the mission and the specific battlefield environment. This is done to determine and evaluate enemy capabilities, vulnerabilities, and probable courses of action. See FMs 34-130 and 101-5.

intelligence preparation of the battlespace (JP 1-02) - An analytical methodology employed to reduce uncertainties concerning the enemy, environment, and terrain for all types of operations. Intelligence preparation of the battlespace builds an extensive data base for each potential area in which a unit may be required to operate. The data base is then analyzed in detail to determine the impact of the enemy, environment, and terrain on operations and presents it in graphic form. Intelligence preparation of the battlespace is a continuing process.

intelligence synchronization matrix - A graphic representation that ties the collection plan to an operation and the commander's intelligence needs.

interagency - Activities or operations conducted by or through coordination with two or more agencies or an agency and one or more services of the same nation.

interagency operations - Any action which combines the human and material resources of two or more independent organizations, be they governmental, international, or private, in prosecution of a common objective. See FM 100-5.

interdict - Using fire support or maneuver forces; 1. To seal off an area by any means; to deny use of a route or approach. 2. A tactical task which is oriented on the enemy to prevent, hinder, or delay the use of an area or route by enemy forces. See FMs 1-111, 1-112, 7-30, 17-95, 71-100, 71-123, and 100-15.

interdiction (JP 1-02) - An action to divert, disrupt, delay, or destroy enemy's surface military potential before it can be used effectively against friendly forces. See FMs 1-111, 1-112, 7-30, 17-95, 71-100, 71-123, and 100-15.

interdiction fire (NATO) - Fire placed on an area or point to prevent the enemy from using the area or point. (See also interdict and interdiction.) See FMs 6-series and 7-90.

intermediate staging base (ISB) - A logistics base established to provide support to deploying units enroute to an operation; area established to ensure continuity of support. The use of an ISB allows supported tactical and operational commanders time to gather additional intelligence on the area of operations and finalize plans following briefings and rehearsals, and provides time during which units may redistribute and finalize their accompanying loads. See FM 100-15.

internal defense and development (IDAD) (JP 1-02) - The full range of measures taken by a nation to promote its growth and to protect itself from subversion, lawlessness, and insurgency. It focuses on building viable institutions (political, economic, social, and military) that respond to the needs of society. (See also foreign internal defense (FID).) See FMs 100-20 and 100-25.

internal security (JP 1-02) - The state of law and order prevailing within a nation. (See also internal defense and development (IDAD) and foreign internal defense (FID).) See FMs 100-20 and 100-25.

interned (JP 1-02) - A casualty definitely known to have been taken into custody of a nonbelligerent foreign power as the result of and for reasons arising out of any armed conflict in which the Armed Forces of the United States are engaged. (Army) - 1. Battle casualties taken into custody by a nonbelligerent foreign power as a result of any armed conflict. 2. Anyone taken and kept as a prisoner of war.

interoperability (JP 1-02, NATO) - 1. The ability of systems, units, or forces to provide servicesto and accept services from other systems, units, or forces and to use so services exchanged to enable them to operate effectively together. (DOD) 2. The condition achieved among communications-electronics systems or items of communications-electronics equipment when information or services can be exchanged directly and satisfactorily between them and/or their users. The degree of interoperability should be defined when referring to specific cases. See FMs 100-5 and 100-6.

intervisibility (IV) - The condition of being able to see one point from another. This condition may be altered or interrupted by weather, smoke, terrain masking, dust, or debris. (See also concealment and cover.) See FM 34-130.

intervisibility line - A ridge or horizon beyond which equipment or personnel can be hidden from observation. (See FM 34-130.)

in-transit visibility (Army) - The capability to identify the location of resources at any moment in the distribution pipeline. See FMs 10-1 and 55-2.

intrusion (JP 1-02) - The intentional insertion of electromagnetic energy into transmission paths in any manner, with the objective of deceiving operators or of causing confusion. (See also electronic warfare (EW), jamming; and meaconing, intrusion, jamming, and interference (MIJI) report.) See FMs 34-1, 34-40, and 100-6.

inversion - An increase of air temperature with increase in altitude (the ground being colder than the surrounding air). When an inversion exists, there are no convection currents and wind speeds are below 5 knots. The atmosphere is stable and normally is considered the most favorable state for ground release of chemical agents. (See also haze, lapse, and neutral.) See FM 3-6.

irregular forces (JP 1-02) - Armed individuals or groups who are not members of the regular armed forces, police, or other internal security forces. See FMs 100-20 and 100-25.

irregular outer edge (JP 1-02, NATO) - In land mine warfare, short mine rows or strips laid in an irregular manner in front of a minefield facing the enemy to deceive the enemy as to the type or extent of the minefield. Generally, the irregular outer edge will only be used in minefields with buried mines.

isolate - A tactical task given to a unit to seal off (both physically and psychologically) an enemy from his sources of support, to deny an enemy freedom of movement, and prevent an enemy unit from having contact with other enemy forces. An enemy must not be allowed sanctuary within his present position. (See also encirclement.) See FMs 7-7, 7-8, 17-95, and 71-123.

Updated 27 July 1997.

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