Fuel Consumption Example with P-51

[Neckbeard]

I tested the fuel consumption on the p-51 against the flight planner in the 1945 AAF manual. I put some notes on imgur if anyone wants to try it.

 

https://imgur.com/a/1w0xVtH

[Tiger4-2]

I tested the fuel consumption on the p-51 against the flight planner in the 1945 AAF manual. I put some notes on imgur if anyone wants to try it.

 

https://imgur.com/a/1w0xVtH

Well, I'm new to DCS so I'm not sure how much of this is modeled but....in regards to the real aircraft this is how you would use the fuel burn chart.

 

Ideally your flight plan would go like this.

 

Fly from point A, heading 040° for 120 miles. Altitude 8000, airspeed 120 knots.

 

So we start with compass Heading 040°, then we account for Deviation(how the aircraft affects the compass), in this example we'll use +2°, which gives you a magnetic heading of 042°. Magnetic Variation for that area is 6 degrees East, and since it's East we add to our magnetic course, so our true course is 048°.

 

Now let's say the wind for that day is from 325° at 12 knots. And your indicated airspeed is 120 knots. It's important to note that due to inherent error present during the installation of airspeed indicators, what you see indicated is off by a few knots. You can look up the airspeed calibration in the pilots operating handbook. So let's say at 120 knots with the canopy closed, the airspeed correction is 2.5. this gives you a calibrated airspeed of 122.5 knots, which you can use to find ground speed and drift angle. Ground speed is in mph so you'll need to convert your true airspeed from knots(1 knot=1.15 mph), and you end up with 140.8mph.

 

From here the easiest thing is to plug what you have into an E6B flight computer, as calculating all of the following by hand is extensive and takes a while. With all of what you have so far you end up with:

 

Wind correction angle of -5°, which gives you a true heading of 043° and a true groundspeed of 139mph.

 

So now with all of that done, you can calculate the time of flight minus the flight plan, in this case 51.8 minutes, or 51 minutes and 48 seconds. Then you apply that time to your fuel burn per hour for 8000 feet at cruising rpm, let's say 20 gallons per hour, and you end up needing 17.27 gallons for the trip.

 

Now look in the manual and find the fuel requirements for startup and taxi, takeoff, and the 8 minute climb to 8000 feet, then add a bit I'm case you get lost and boom. Fuel quantity solved.

 

 

 

 

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Edited April 21, 2020 by Tiger4-2