ATP-3-09-30 Observed Fires Download
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Chapter 4 4-6 ATP 3-09.30 28 September 2017 the observer does not request a shell fuze, for the fire for effect phase, the fire direction officer determines the shell fuze combination. The unit SOP may designate a standard shell fuze combination. 4-40. If the observer desires a shell and fuze combination other than standard, the shell and fuze "in adjust" is announced first, then the shell and fuze "in effect". For fire for effect missions, it is not necessary to announce "in effect" after the shell and fuze request. Followed By 4-41. This is part of a term that indicates a change in the rate of fire, in the type of ammunition, or in another order for fire for effect. For example, if observer wants the ammunition white phosphorous (WP), then HE, the request is WP FOLLOWED BY HE. Projectile 4-42. An observer can request a specific munition, however, the FDC has the final determination based upon METT-TC. The following projectile types are available for request: HE-high explosive, hexachloroethane zinc, WP-white phosphorous, red phosphorous (RP) (mortars only), ILLUM-illumination dual purpose improved conventional munition (DPICM),-antipersonnel improved conventional munition, SMOKE, SCATMINE-scatterable mines, EXCALIBUR, precision guided munition, and guided multiple rocket launch system (GMLRS). EXCALIBUR, accelerated precision mortar initiative (APMI), and GMLRS are precision-guided munitions and are most effective when paired with mensurated coordinates. Fuze 4-43. Fuze quick is the fuze normally used during the adjustment phase. If the observer desires fuze quick or if a projectile that has only one fuze is requested, fuze is not indicated. Illumination, improved conventional munitions (ICM), and smoke projectiles are fuzed with time fuzes; therefore, when the observer requests ILLUMINATION, ICM, or SMOKE, the observer does not announce TIME. Fuze types are as follows: PD- point detonating, VT-variable time, MT-mechanical time, ET-electronic time, MTSQ- mechanical time super quick, DELAY, and MOF-multi option fuze (mortars only). Volume of Fire 4-44. The observer states the volume of fire desired in the fire for effect in rounds per howitzer. For example, 3 ROUNDS, indicates the observer desires the unit to fire three volleys in effect. Distribution 4-45. The observer may control the pattern of bursts in the target area. This pattern of bursts is called a sheaf. Unless otherwise requested, the artillery computer system assumes a circular target with a 100 meter radius. The artillery computer system determines individual weapon aiming points to distribute the bursts for best coverage of this type of target. A converged sheaf is a special sheaf in which each piece fires a unique time, deflection, and quadrant elevation to cause the rounds to impact at the same point on the ground. A converged sheaf is typically used for small, hard targets. An open sheaf is a special sheaf in which each piece fires a unique time, deflection, and quadrant elevation to cause the rounds to impact in a straight line, perpendicular to the gun-target line and centered on the target, with bursts spaced one effective burst width apart. Special sheaf (linear, rectangular, circular, or irregular) of any length and width may be requested. If target length, or length and width are given, the observer must also give attitude. If target length is greater than or equal to five times the target width, the artillery computer system assumes a linear target. The mortar ballistic computer assumes the target is linear and fires a parallel sheaf unless the observer requests a special sheaf. The parallel sheaf distributes the bursts of all pieces similar to the distribution of weapons on the gun line due to firing the same data with each piece.