TC 3-22.91 Mortar Fire Direction Procedures August 2025

TC 3-22.91: Mortar Fire Direction ProceduresIntroductionTC 3-22.91 provides doctrinal procedures for mortar fire direction within U.S. Army units. It supports fire direction center (FDC) personnel in delivering timely and accurate indirect fire. The manual outlines techniques, calculations, and communication protocols used in fire missions. It is designed for use by mortar squads, platoons, and fire support teams across all operational environments and phases.Table of ContentsChapter 1: Mortar Fire Direction FundamentalsChapter 2: Fire Mission ProcessingChapter 3: Fire Direction Equipment and CommunicationChapter 4: Fire Commands and Fire OrdersChapter 5: Adjustments and CorrectionsChapter 6: Special Munitions and MissionsChapter 7: FDC Training and EvaluationChapter SummariesChapter 1: Mortar Fire Direction FundamentalsIntroduces the purpose and function of the FDC in mortar operations. Explains key roles, such as fire direction officer, fire direction NCO, and computer. Defines types of mortar fire missions and essential terminology, including grid, polar, and shift from known point.Chapter 2: Fire Mission ProcessingOutlines the sequence for processing fire missions, from observer call for fire to execution. Details include target location methods, determination of direction, deflection, charge, elevation, and time. Includes correction for MET (meteorological) data and observer-target relationships.Chapter 3: Fire Direction Equipment and CommunicationDetails required FDC tools: plotting boards, GFTs, handheld devices, and advanced fire control systems. Discusses secure communications, call signs, frequencies, and data transmission protocols. Emphasizes speed and accuracy in data relay between FOs, FDCs, and mortar sections.Chapter 4: Fire Commands and Fire OrdersProvides standard fire commands and how they are formatted and transmitted. Breaks down sequence: warning order, deflection, charge, elevation, method of fire, and method of control. Explains time-on-target and coordinated fire mission techniques.Chapter 5: Adjustments and CorrectionsTeaches techniques for bracketing, creeping fire, and corrections based on observer reports. Covers error analysis and refining firing data. Introduces probability-of-hit considerations and when to fire for effect. Highlights adjustment safety margins near friendly units.Chapter 6: Special Munitions and MissionsExplains employment of smoke, illumination, and precision munitions. Covers variables such as wind drift, burn time, and battlefield visibility. Discusses special missions like registration, final protective fires, and immediate suppression.Chapter 7: FDC Training and EvaluationOutlines training methods, including simulation, practical exercises, a Read more