FM-3-09 Fire Support and Field Artillery Operations Download
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Appendix D D-18 FM 3-09 30 April 2020 battlefield. As sleep loss begins to accumulate, both physical and mental effects are observed in varying degrees. Most of the following effects can occur after 24 hours without sleep: Tasks may be omitted as a result of a momentary lapse into sleep (falling asleep with eyes open). Vigilance decreases rapidly, resulting in missed critical signals. Ability to focus on a task for more than a brief period decreases noticeably. Memory becomes faulty, particularly short-term memory. This makes it difficult to learn new information, follow instructions, or remember recent decisions. Response to events or instructions slows. One seems to be operating in a daze. The ability to formulate and make sense from information becomes severely degraded. It takes longer to perform simple tasks such as plotting grid coordinates. Accuracy suffers. The ability to reason logically is degraded, which may result in snap judgments. Problems with communication arise. One has difficulty understanding or articulating even simple messages. A wide range of mood changes, characterized by depression, anger, lack of patience, and euphoria, can occur. D-127. Sleep loss is cumulative over time. The number of hours needed to recover is directly related to the number of hours sleep was deprived. As a rule of thumb, a minimum of 6 hours rest is required for every 24 hours without sleep. Fatigue is the result of excessive work and sleep loss. The latent effects of fatigue may linger for about 3 days following sleep deprivation of 48 hours or more. SECTION VII – COLD WEATHER OPERATIONS D-128. Fire planning for cold weather operations is no different than that required for more temperate regions. However, the fire support planner must consider that artillery weapon systems may have limited mobility in snow and ice that will also affect ammunition supply and increase to time to accomplish tasks. MUNITIONS D-129. The following are considerations in the employment of various munitions in cold weather operations: Make maximum use of airburst munitions. HE-point detonating, HE-delay, improved conventional munitions, and field artillery delivered mines are ineffective in deep snow and unfrozen bogs. At least 40 percent of the blast from these munitions is smothered by the snow. Hexachloroethane smoke is not effective because canisters are smothered in the deep snow. White phosphorous is effective; however, phosphorus may burn undetected in the snow for up to three to four days and may be a hazard to friendly troops subsequently moving through the area. Overall, variable time or multi-option artillery fuzes are good fuzes for cold weather operations. However, snow and ice may cause them to detonate prematurely. Also, extreme cold may cause a higher dud rate. Extreme cold weather will affect the range of weapons. Low temperature may cause illuminating rounds to malfunction as the result of freezing the parachute and its components. TARGET ACQUISITION AND OBSERVATION D-130. Considerations for employing FOs in cold weather operations include: Equip FOs with snowshoes or skis to allow them to move quickly. Relieve observers in static positions frequently. Update visibility diagrams regularly because drifting snow changes visibility. Use amber filters on binoculars and observation devices to reduce the incidence of snow blindness. Avoid using ground bursts that may be difficult to observe in deep snow.