Benchmark

The next step is to enter fuel flow data and fit curves to the data to model the fuel usage of the engine.

There are three possible sets of data, for Full Rich, Best Power and Best Economy. Most injected engines only have fuel data for Best Power and Best Economy. Lycoming does not publish precise fuel flow charts for carbureted engines. Where there is no fuel data, you just don't enter anything and Benchmark will 'understand' your situation.

Following the same method used for engine power data, here is how I handle tracing the fuel flow charts.

I created the grid of lines as before.

I used the Spline tool in WildTools to trace the curves.

I separated off the best power points and used the Dimension Point tool to create the fuel flow points.

For fuel flow, you can set the Benchmark preferences to gallons, pounds, liters or kilograms.