Light Mortar Employment: Achieving Responsive Fires for Company Level Operations
by 1stLt Niles Moffat
The purpose of maintaining 60mm mortars at the company level is to provide responsive fires directly tied into the scheme of maneuver. Therefore, the best way to employ 60mm mortars is in such a way that provides the greatest amplification of combat power. In this sense, combat power is defined as the total destructive force we can bring to bear against the enemy. Our ability to support maneuver elements with accurate and responsive fires is vital to our capability to close with the enemy and ultimately defeat him. We can achieve this through multiple methods of employment, but for this article, we will focus on conventional Fire Direction Center (FDC) and direct alignment used as a consolidated section.
60mm mortars are incredibly responsive when used properly. There is a tendency to want to use 60s in conventional FDC mode with some forward observer passing calls for fire and corrections over radio. This tendency comes from both ends of the chain of command. It is tempting when developing fires in support of maneuver to want to place mortars in a mortar firing position and leave them there until the mission is complete. We do this because it is simple when planning deconfliction, communication plans, and signal plans. Conversely, many of our 60’s squad leaders return from Advanced Mortarman Course (which has a heavy focus on FDC) wanting to demonstrate their newly acquired skills.
Conventional FDC with Enhancements
While FDC has its uses, it often takes away 60’s greatest attribute: responsiveness. The ability to apply fires quickly and accurately requires us to make the kill chain between sensor, approver, and shooter as short as possible. FDC struggles to do this because of the gap in the kill chain between sensor and shooter. One method we found to shorten this gap is through the use of Small Unmanned Aerial Systems (SUAS). During an urban defense while participating in Adversary Force Exercise 1-22, our company employed mortars in conventional FDC while co- located with the FiST and a SUAS operator. The SUAS operator would spot targets and provide an eight-digit grid. He then passed to our mortar section leader who, with the use of an LHMBC, was able to rapidly generate gun data for the section. Meanwhile, the FiST cleared the fires and requested approval from the company commander. Upon receipt of approval, the FiST gave the command to fire. The time from when we spotted an enemy to the time we had rounds on target was on average less than 90 seconds, with some fire missions completed in under 60 seconds.
Although this method of employment achieved success, it has several disadvantages. By co- locating the FiST, mortar section, and SUAS, we created a large signature in both the physical sense and the electromagnetic sense. A single strike from the enemy would take out a large amount of the company’s assets. Additionally, our defense incorporated several fire support control measures which enabled us to rapidly clear fires. A more complex scheme of maneuver would require much more detailed integration, thereby increasing the time between detection and destruction. While we have only used this method in a defensive setting, it has potential for offensive schemes of maneuver as well.
To increase the survivability of our section we used hide and shoot tactics in the urban environment. We left baseplates and stakes emplaced and had the squads and their tubes stay indoors until they received a fire mission. Once the fire mission was complete, we broke down and reapplied camouflage to the baseplate with urban debris. While this tactic took away some of our responsiveness, it bought us increased survivability. Furthermore, by calling a fire mission while the section leader was pulling gun data from the LHMBC, we found that our tubes were often up and waiting for the gun data rather than us having to wait on them.
Direct Alignment
Now let us consider the more responsive employment options. The simplest way to achieve responsive fires is to employ 60s in direct lay, allowing the shooters to see their targets and their effects. However, this is the least survivable way of employing this asset. The next best option available is direct alignment. This allows our forward observer to see the target, the effects of our fires on said targets, and our maneuver elements all while keeping our 60’s out of the target’s line of sight.
Direct alignment can be used in both the offense and the defense. Furthermore, it links the sensor and shooter. The final piece of the kill chain is the approver. This approval lies with the company commander or is delegated to the weapons platoon commander. When seconds matter, requiring the section leader to ask for approval for each fire mission is extremely time consuming. Our ability to provide clear intent and approve select fires in the planning process is vital to achieve responsive fires. Providing detailed engagement criteria, target precedence, and using fire support control measures are ways to grant that approval without relying on in the moment communications.
One way we achieved responsive fires with direct alignment during offensive operations was through establishing Coordinated Fire Lines (CFLs) tied to maneuver’s phase lines. Once a maneuver element reported crossing a phase line, the mortar section acknowledged and shifted fires to targets beyond the subsequent CFL. This method of employment required careful planning to ensure fires were clear at each CFL and for each maneuver element. Furthermore, this method requires working communication gear and/or the forward observer to visually track lead trace. Another way we achieved responsive fires in the offense was by giving the section their own engagement area. For this attack, we tasked the section with isolating the objective. From there we essentially created an engagement area exclusively for the 60mm mortar section and ensured no friendly forces entered without requesting approval from the company commander.
For defensive fires, we chose to integrate the mortar section into the front line of our defensive position as much as possible. This eliminated the danger of overhead fires and allowed our mortars to engage targets throughout the entirety of the engagement area – a challenge we encountered when we would place our section on one of our flanks. Once we ensured geometries were clear, we provided specific engagement criteria tied to our trigger lines. This allowed the section leader to fight his section without additional oversight. The danger with such a strategy is the apparent gap created by removing riflemen from that section of the line. This danger is mitigated by analyzing our defense to identify where we can risk a gap and by then covering the gap with direct fires from adjacent positions.
That being said, for more complex schemes of maneuver we owe it to our Marines to have detailed knowledge of all the fires we employ. This is certainly the case when we are supporting closure on an objective, operating with air assets in support of maneuver, or in operations involving a civilian populace. However, the desire to hold all fires “close to the chest” hampers small unit leader initiative and degrades our combat capability. While there are times we must assert direct control over our fires, we should strive to develop schemes of maneuver which enable small unit leader initiative and function off commander’s intent.
Conclusion
Regardless of employment method, we must learn how to tie our organic fires asset into our SOM to provide the most accurate and responsive fires possible. We demonstrated multiple ways to achieve success, but every scenario requires thorough analysis before committing assets. Some questions we have moving forward are how well these TTPs will work in the INDO-PACOM region. Our methods worked well in the open spaces of 29 Palms and Camp Pendleton, but the jungle is an entirely different environment. Will dense vegetation negate the usefulness of UAVs? What are the impacts of limited visibility on direct alignment? How do we track lead trace in the jungle? What is the most reliable communication pathway to call for and approve fires? Our ability to apply, modify and continue to challenge and question these lessons learned to our future operating environment is vital to our readiness as a warfighting organization.
1stLt Niles Moffatt is the Weapons Platoon Commander for G Co V25. He can be reached at nilesmoffat@gmail.com.