Armourer's Terminology from "F" to "W"

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FORWARD FIRING WEAPONS: Weapons propelled in a forward direction. Examples: missiles, rockets and guns.
FMU: Pronounced "ef em you". Munition fuze unit, i.e.: FMU-57/A tail fuze.
FRAGMENTATION ENVELOPE: The pattern made by weapon fragments which surround a high explosive weapon at any point in time at or after detonation.
FUNCTIONARY DELAY: The controlled time interval between initiation of the firing device or explosive train and the actual detonation of the weapon. Delay may be provided by pyrotechnic, electrical, or clockwork devices and may commence at weapon release from the aircraft or at impact.
FUSE: In ordnance applications, a pyrotechnic device which is usually a length of combustible cord used to initiate an explosive charge.
FUZE: A term for the mechanical or electrical device with explosive components used to initiate the detonation of a weapon by an action such as hydrostatic pressure, electrical energy, impact, mechanical time, or a combination of these, at the desired time.
FUZE SAFETY SYSTEM (NATO): The aggregate of devices (environment sensors, launch event sensors, command functioned devices, logic networks) included in the fuze to provide safety but which prohibits arming and functioning of the fuze through all environments during transportation storage, handling, installation and launching of the munition until a safe separation distance from the aircraft has been achieved.
FUZE SETTINGS: The pre-flight or in-flight selected fuze arming delay or functioning time.
FUZED BOMB HOLDING AREA: An area where weapons ready for loading on aircraft or fuzed, high explosive bombs removed from aircraft are stored.
FUZING AREA: A designated area in which explosives are prepared for use. A fuzing area may be specially prepared building or a selected open site.
FUZING SYSTEM: A physical system designed to sense a correct release environment, to preclude unintentional initiation of the explosive train and to cause an item of ammunition or aircraft store to function at the desired position and time.
FUZING: A general term applied to the assembly and/or preparation of explosives for use.
FZ: Fuze - related items.

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G-FORCE: Forces compared to one gravity; when, for example, a fuze is subjected to a force of 13 g's, a single component of the fuze parallel to the direction of the force weighs 13 times as much as it does when the fuze is at rest. G-forces can be used to arm or fire fuzes. See also "set back force".
GAU: Aircraft gun unit.
GF: Gun - related items unit.
GPU: Poded guns unit.
GUIDED MISSILE: An unmanned air vehicle whose trajectory or flight path is capable of being altered by an external or internal control or guidance system.
GUU: Miscellaneous gun unit.

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HYDROSTATIC FUZE: A fuze used with depth bombs for underwater detonation. Initiation caused by hydrostatic pressure.

IMPROVISED EXPLOSIVE DEVICE (IED): Criminally placed or fabricated devices which incorporate destructive, lethal, noxious, pyrotechnic or incendiary chemicals designed to destroy, disfigure, distract or harass. They may incorporate military stores but are usually devised from non-military components.
IGNITER: Complete system of initiator, booster charge and main charge. Designed to produce sustained generation of hot particles, flame and gas to initiate an explosive train.
IMPACT FUZE: A fuze in which detonation is initiated by the force of impact and which usually functions instantaneously or after a short delay. With rocket fuzes, the term Point Detonating is used.
INCENDIARY: Material designed to start local combustion (fires).
INERT: An article, particularly an aircraft store, which contains no explosive or flammable components.
INTRUSION: The distance into the fuze well which a fuze extends when it is fly screwed in.

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JETTISON: Releasing an airborne weapon or store by means of an emergency or secondary release system for safety purposes or to prepare for air combat. Weapons are normally jettisoned in a safe condition.

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KCAS: Knots Calibrated Air Speed; Indicated air speed corrected for aircraft instruments errors. Errors are usually insignificant. for most purposes, KCAS can be equated with KIAS.
KIAS: Knots Indicated Air Speed; A measurement of aircraft speed not corrected for effects of air density and temperature. for a given true air speed, indicated air speed decreases as air density decreases or temperature increases. It is indicated air speed which is sensed by a fuze arming vanes.
KTAS: Knots True Air Speed; The actual speed of the aircraft through space. True air speed is computed by correcting indicated air speed for effects of air density and temperature. The actual speed of the aircraft over the ground is determined by correcting KTAS for effects of wind.

LAU: Pronounced "l�w" as in loud or wow. Aircraft installed missile/rocket launchers (aka rocket pods), i.e.: LAU-5003/B.
LOAD CREW: A crew of air weapons personnel who are qualified and certified to conduct loading operations specific to the air weapon and aircraft applicable.
LOAD CREW CHIEF: An air weapons systems technician (usually the rank of Master Corporal) who is qualified, certified and responsible for the direct supervision of a load crew during loading/unloading operations.
LOADING: An operation that installs airborne weapons or stores on or in an aircraft.
LONG DELAY: Term applied to fuzes in which detonation is delayed for a relatively long period of time after impact for purposes other than providing weapon penetration (e.g., area denial). These delays may range from several minutes to days.
LOW-DRAG BOMB: A loosely applied term which can refer to a conical-finned bomb body or to a bomb fitted with retarding fins which not allowed to open at weapon release. Applied to MK 80 series bombs due to their slender, pointed shape.
LUU: Pronounced "lou". Illumination units, i.e.: LUU-2/B.

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MAIN CHARGE: The main explosive charge in a bomb or projectile which consists of a relatively insensitive explosive substance. It requires an initiator booster train to generate a detonating wave powerful enough to cause it to explode.
MASTER CORPORAL RANK: A working supervisory rank in charge of Corporal and Privates in the Canadian Air Force. Is equivalent to E6 rank in the US Air Force. The Canadian Forces non-commissioned rank structure being: Private(recruits), Private(trained), Private, Corporal, Master Corporal, Sergeant, Warrant Officer, Master Warrant Officer, and Chief Warrant Officer.
MAU: Pronounced "m�" as in maw. Miscellaneous armament items unit, i.e.: MAU-50 bomb rack.
MDU: Miscellaneous simulated munition unit.
MECHANICAL FUZING: A fuze which depends primarily upon events of a mechanical or physical nature for arming and functioning. Most mechanical bomb fuzes utilise an arming vane which rotates in the airstream to provide arming energy.
MHU: Pronounced "em ach you". Munition handling equipment.
MISSILE: A general term describing an armament store designed to be dropped or projected from an aircraft or discharged from a gun or projector.
MISSILE LAUNCHER: Name for the device from which a self-propelled weapon that is controlled in flight is started on its course. See also rocket launcher.
MSL: Main Sea Level.

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NO-ARM SPEED: That air speed at which no fuzes in a given group can be expected to arm. The no-arm speed is critical in determining safety factors involved in take-off, landing, and on-deck handling.
NOSE FUZE: A fuze which is mounted in the nose well of a bomb, rocket, or missile.

OUT-OF-LINE SAFETY: A safety feature on most fuzes in which one or more components of the explosive train are not aligned which respect to the other components until the fuze arms.

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PICKLE: An informal term used to describe the action of releasing a weapon by the pilot or to the bomb release control (pickle switch) used for this action.
POSITIVELY RIGGED: A method of rigging an arming wire so that the arming wire is always pulled from the bomb when the weapon is released. In this case, there in no option available to the pilot with respect to arming wire withdrawal.
POST-LOADING: A quality assurance inspection conducted after completion of loading.
PRACTICE AMMUNITION: Ammunition either designed or relegated for practice purposes. Practice Ammunition has some components filled with explosives.
PRACTICE BOMB: Small bombs used for general bombing practice to simulate trajectories of large bombs.
PROPELLANT: Material consisting of fuel and oxidizer, either separate or combined in a mixture or compound, which, if suitably ignited, changes into a large volume of hot gases capable of propelling a missile.
PYROTECHNIC: A chemical mixture of oxidizing and reducing agents capable or reacting exothermically. Such mixtures are used to produce light, heat, smoke or gas and may also be used to introduce delays into explosive trains.

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RADHAZ: An acronym for Radiation Hazards which refers to the electromagnetic radiation field from adverse effects of ordnance equipment. A RADHAZ-free area is one in which certain ordnance can be handled and stored without risk of malfunction caused by nearby electromagnetic sources. (Also referred to as HERO-Hazards of Electromagnetic Radiation to Ordnance.)
RETARDED DELIVERY: The term used to describe a weapon delivered with the retarding funs or other retardation device open. Informally referred to as "Snakeye" delivery.
RIPPLE RELEASE: The sequential release of weapons from the bomb rack at specific intervals.
ROCKET: A device that fires self-propelled types of ammunition. This is usually an unguided missile which produces a thrust derived from the controlled ejection of gases generated by the propellant.
ROCKET WARHEAD: The rocket component that contains the high explosive charge or other filler, the booster and the fuze, propelled by a rocket motor.
ROCKEYE: The nickname of a cluster bomb unit designated the MK 20, Antitank bomb, Cluster. If it is designed primarily as an anti-armour weapon.

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SAFE ESCAPE DISTANCE: The minimum distance between the delivery aircraft and the weapon impact point which will ensure that the risk of fragmentation damage to the aircraft is at or below an acceptable level. This distance determines the minimum release speed and altitude.
SAFE JETTISON: The release and separation of a weapon in which the fuze remains unarmed during free-fall and ground impact. It does not initiate the function of the weapon.
SAFE SEPARATION: The distance between a bomb and the delivery aircraft when the bomb arms is called the safe separation distance. It is based on the assumption that a percentage of bombs will detonate at fuze arming. A safe separation, therefore, it a distance from the bomb which will provide little or no damage to the delivery aircraft from its own bomb fragments. Because this distance is dependent upon fuze arming time and the probability that a fuze might early-burst, the arming time must be selected carefully so that it is compatible with the aircraft type, delivery maneuvers, air speed, altitude, and other factors.
SALVO: To release several bombs at the same time. A high risk of bomb-to-bomb collision exist with this type of release.
SET-BACK FORCE: The general term used to describe the action of acceleration forces on rocket or projectile fuzes. Set-back can be used as an environmental feature to arm a rocket fuze.
SIDE DRIVE: An anemometer-type device mounted on the side of bomb which imparts rotary action to arm a tail fuze.
SOLENOID: An electrically operated device on the aircraft bomb rack to which the arming wire is attached. when energized, the solenoid retains the arming wire a weapon release. If the fuze is to be dropped "SAFE", the solenoid is de-energized and the arming wire is dropped with the weapon.
STICK: Term applied to several bombs released in ripple sequence with a preselected interval between each bomb. This interval is usually 60 milliseconds or more; the complete release can then be expressed as a "stick length" (a stick length of 240 milliseconds, etc.). Also referred to as "Stik".
SURFACE BURST: Detonation of ordnance at or close to the surface. Normally this implies detonation of a bomb without any significant penetration into the ground. It may also imply a malfunction of a weapon designed to airburst.

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TAIL DRIVE: A mechanical device with arming vane used to impart rotary motion to a tail-mounted fuze which is not exposed to the airstream.
TAIL FUZE: A fuze which is mounted in the tail well of a bomb.
TIME FUZE: A fuze which is designed to operate after the lapse of a pre-determined time. Time fuzes may be designed to provide an airburst, but the term may also refer to long delay fuzes which function after the weapon strikes the target.

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UNRETARDED DELIVERY: The term used to describe bomb delivery in which the trajectory of the weapon is not shortened by the use of retard fins or parachute. sometimes referred to as "freefall".

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VT: The designation of a proximity sensing device which causes weapon detonation in proximity to the intended target. In air-to-surface weapons, a VT device produces weapon detonation prior to weapon impact.

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WEAPON: An offensive or defensive instrument used to destroy, injure or threaten an enemy.
WEAPONS SYSTEM HARDWARE: Mechanical, electromechanical and electronic components of an aircraft weapons system which are used to suspends, launch, release or fire an air weapons store. This hardware may house a propellant actuating device designed to ensure positive disengagement of an air weapons store from its suspension point on the aircraft.

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