Oktas8,
Can't agree with your analysis. It would be fine if kerosene were a pure carbon.
(Carbon(12)+Oxygen Molecule(32))/Carbon 12 = 44/12 = 3.66 = 293/80
However, fuel is a hydrocarbon so each carbon atom has hydrogen atoms associated with it.
As was noted earlier, the two most prominent byproducts of kerosene combustion are CO2 and H2O.
The hydrogen present throws off the ratio developed above.
Fuel density varies around the world based on the carbon/hydrogen ratio of the crude used to refine it.
On average, the ratio of CO2 to fuel is 3.155.
Therefore, 80 tonnes of fuel would produce 252 tonnes of CO2.