Yep, and if you don't have a "miles per gallon" feature on your avionics you can do it manually. The "app" for power setting can be as simple as a $5 calculator. Once speed is stabilized, divide ground speed by fuel flow. Move the black knob(s) to maximize the number.

 

Bill Harrelson

N5ZQ 320 2,150 hrs

N6ZQ  IV  400 hrs

 

 

 

Using air data set to display NM/Gallon, a pilot can make 10% changes in power and quickly determine the benefit or loss after speed stabilizes. On my Shadin, I did exactly what George did, pulled power back thinking I could extend my range. My nm/gallon dropped from 6.0 to 5.x resulting in a longer trip and burning more fuel to cover the same piece of dirt/water. Increasing power got the NM/Gallon back up and higher. Sounds like a nice app to create now that we can access ARINC 429 data on certified systems. Such an app would give best altitude, route and power. Or, just buy a jet and the app is included in a expensive box.
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