Originally Posted by
Gauges and Dials
Surely as a professional pilot you know that the impact on fuel consumption of added weight is vastly different for aircraft (where energy is consumed to counteract gravity as well as to overcome friction losses in moving the aircraft from point A to point B) than for wheeled vehicles (where energy is consumed only to overcome friction losses). The energy cost of "tankering" in a typical passenger automobile is probably very close to unmeasurably small.
And how often does someone drive an extra few miles to buy fuel because it's twenty cents/pence cheaper? The penalty for carrying an extra few gallons of fuel may be unmeasurably small, but the fuel to drive the extra distance isn't...