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albar965 / littlenavmap

Little Navmap is a free flight planner, navigation tool, moving map, airport search and airport information system for Flight Simulator X, Microsoft Flight Simulator 2020, Prepar3D and X-Plane.
https://albar965.github.io/littlenavmap.html
GNU General Public License v3.0
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More precise fuel calculation #314

Open albar965 opened 5 years ago

albar965 commented 5 years ago

Add layers of around 5000 or 10000 ft to get a more precise fuel calculation. related to #255

ghost commented 5 years ago

For planes like the PMDG DC-6 it would be great if this could be sliced in multiple windows: based on time and/or engine settings: Take off power is only allowed for max 2 minutes (@2800 rpm, 1385lb/hr+1.3g/min), followed by METO power(@2600rpm, 1385 lb/hr), followed by a cruise profile (@2300 rpm), followed by a cruise profile (@2200 rpm). The RPMs vary somewhat with different profiles, but seem like a good demarcation for engine fuel consumption in a particular phase of flight.

albar965 commented 5 years ago

Hi, takeoff and METO power are used on too short periods to consider them in fuel calculation. Takeoff is even a part of taxi fuel. METO goes into climb.

That's why I call it average fuel flow on climb.

And at the end only elevation counts (and ISA deviation, etc.) and not time. This is the parameter which changes engine performance and thus climb rate and fuel consumption.

The layers would consider a cruise profile but I have to see if all this is doable with reasonable effort. Not soon. I have no plans for adding different cruise profiles. You can simply create a lnmperf file for each one.

Alex

ghost commented 5 years ago

What about recording fuel at each waypoint of the flightplan?

albar965 commented 5 years ago

The performance data is universal and not attached to a flight plan. Therefore, it would not make sense to store waypoint related data.

I think that different performance "altitude layers" for climb and cruise are more helpful.

I plan to add consumed fuel numbers to the flight plan table but currently this is static and does not change in flight. Alex

ghost commented 5 years ago

I guess my angle comes from the desire to fly on the numbers (right now focusing on fuel efficient flight) and figuring out what the numbers would be in the first place:-) Suffice to say: I can't wait until 2.2 will be released:-)

albar965 commented 5 years ago

You can get the current beta 2.2.1 by changing the update check in dialog Options on tab Startup. Be aware that the manual is not updated yet. Alex