Dominant Logistics
Keeping the Combustibles Flowing
Someone once coined the phrase "Amatuers talk tactics; professionals talk logistics." I can't help but think that whomever this person was gained their logistics experience in the area of combustibles. For the newcomers, combustibles are the fuel, heavy ammunitions, and other munitions that are consumed in the course of conducting warfare. At the tactical level, this is arguably the biggest headache of all.
Unfortunately, the cause of the headache isn't the systems we are supporting - it is the strategic planners that live in a paper world that tends to bear little resemblance to reality. For example, the official party line is that the Abrams tank has an unrefueled range in excess of 200 miles. In the real world, the Abrams is lucky to get over 150 miles under most conditions and 100 miles in some documented cases. While a strong case is often made that this is because the Abrams is a fuel hog, the reality is that ALL main battle tanks are fuel hogs - it is only a matter of how bad they are. To deal with the challenges of supporting these systems in the future, we need to adopt some new concepts for supportability.
Consumption to Capacity Ratio
First, we need to look at Consumption to Capacity ratio (C2C). The C2C ratio gives us a general overview of how much support a given system will require in the field. This ratio can be viewed in two different ways that concern us here. Following our given example, we'll look at fuel consumption first.
The Consumption value for vehicular fuel is how far the vehicle can travel on the amount of fuel that it holds. The Capacity value is how much fuel it holds. In the case of a modernized M113A3, it can achieve a Consumption range of about 200 to 300 miles depending on conditions with a capacity of 95 gallons of fuel. This gives us a ratio of about 2.5 to 1 which isn't bad. With the Abrams, we can expect a range of around 150 miles on a capacity of nearly 500 gallons of fuel for a ratio of about 1 to 3 which is pretty poor. You'll notice that I'm rounding the numbers extensively and this is because Consumption values are very subjective. We're looking at generalizations here, not specifics.
When we look at ammunition, Consumption becomes even more subjective because now we have to make estimates of the amount of ammunition we expect to need. As with fuel consumption, this number will vary wildly and is probably going to be an average of an assortment of estimates. This average is then compared to the Capacity of ammunition the system holds.
Assigning Sustainment Resources
Once we determine the C2C ratio, we can form an estimate of what is needed for sustainment resources. We need to take two factors into consideration here: the role of the unit and the C2C ratios of the systems within the unit. For example, an Abrams tank has a horrendous C2C ratio for fuel but if the tank is assigned to a purely defensive role where the distance it is required to travel is very limited, the poor ratio is immaterial. This is largely how the Abrams got its bad reputation - other tanks guzzle fuel just as badly but they are being used in defensive or short-range roles whereas the Abrams is often used in long-range cavalry roles.
In general, systems with a C2C ratio of less than 1 to 1 need to have support resources organic to the section using the system. For those lost in the math, this means that every Abrams tank in an offensive unit needs to have a refueling asset for that tank assigned to it's platoon. It also means that each self-propelled howitzer needs an ammunition bearing system assigned to it's battery. When the C2C is less than 1 to 1, the support systems need to be assigned 1 to 1.
If the C2C ratio is a little higher, falling between 1 to 1 and 2 to 1, we need to assign support systems at a ratio of one support system for evey five combat systems. For example, Bradleys need a refueling system assigned for every five Bradleys in the formation. Most SPHs will also need a fuel asset for every five guns as well. With these requirements, the support systems do not need to be assigned to the sections being supported but they should be assigned within the same organization as the supported systems.
For ratios better than 2 to 1, we can keep the support systems at higher echelons as these combat systems are not going to require the constant level of sustainment that other systems require. As previously mentioned, much of this subjective in nature but these are the general guidelines that we can use to help build more effective and sustainable formations.