Energy, Fuels, and Cost Analyses for the M1A2 Tank: A Weight Reduction Case Study 2020-01-0173
Reducing the weight of the Abrams M1A2 tank has been studied by lightweighting three separate components: hull, suspension, and track, resulting in 5.1, 1.3, and 0.6 percent tank mass reductions, respectively. The impact of replacing an existing with a lightweight component on tank performance are evaluated in terms of three metrics: primary energy demand (PED), cost, and tank operational fuel consumption (FC). The life cycle phases included are: preproduction, material production, part fabrication, and tank operation. The metrics for each of the tank lightweight components are expressed as ratios: for example, the sum of PED for the four life cycle phases of the lightweight tank / the PED for the operational phase only of the base case (unmodified) tank. For Army defined duty cycles, a FC/mass elasticity of 0.55 was employed for estimating changes in tank FC upon mass reductions. On a per tank basis, we find that the relative costs to retrofit and operate a tank with a lightweight hull ranges from 19 to 3.5 times those for simply operating (fuel costs) an existing base case tank traveling the same life time distance. As expected, the cost and PED ratios decrease with increasing life time distance traveled. The relative PED values for the lightweight hull range from 2 to 1.1 times the base case PED. To provide a more traditional lifecycle assessment perspective on tank mass reductions, we also include here a refurbishment/refitting analysis of the same three components but in this case there is a choice between a lightweight component and an original heavier component. As expected, these cost and PED ratios are smaller than the corresponding ratios based on base case tank operation only, primarily due to the same life cycle stages (cited above) being used for both base and lightweight tank cases.
John L. Sullivan, Geoffrey M. Lewis, Gregory A. Keoleian, Rob Hart
EcoSpherica LLC, University of Michigan, CCDC Ground Vehicle Systems Center