On Tuesday, November 20, 2012 12:12:23 PM UTC-7, aerodyne wrote:
Using the Pawnee as an example, operating costs are only driven partly

by fuel, if fuel was 12/gal vs 6/gal, tow costs would not double, but

increase by 30-50%.

That's direct fuel cost. The non-fuel costs are also driven by the price of fuel - but indirectly as pass thru.