The authors analyze the practice of tankering fuel, which seeks to lower total fuel costs by having aircraft carry excess fuel when traveling from locations where fuel is cheaper than it is at the destination. To determine whether savings might be achieved, historical flying patterns, fuel prices, and other factors are examined for the C-5, C-17, and C-130 aircraft. The authors examine the changing potential for future cost savings as Air Mobility Command transitions from wartime to peacetime operations.They also discuss the four different price regimes in place at the Defense Logistics Agency, the agency that purchases fuel on behalf of the Department of Defense, and fluctuating market rates. Their research compares the fuel costs of more than 94,700 flights completed without tankering during FY 2012 with estimated costs of those same flights if they had tankered fuel to the maximum extent possible.