Many pilots just carry a copy of the Fuel Tankering Fuel Price Differential graph from the Flight Planning and Performance Manual or use the table below for break-even fuel price based on LRC/.79M cruise and step climb:
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TRIP DISTANCE (NM)/ BREAK-EVEN PRICE RATIO
200 / 1.015
400 / 1.032
600 / 1.046
800 / 1.062
1000 / 1.078
2000 / 1.179
3000 / 1.313
4000 / 1.500
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