Fuel measurments...

[Wrench 9,848]

somebody refresh my (failing) memory ...

the amount of fuel in the tanks is measured in kg, or liters, or ??? 

Got 5 fuel tanks to correct....

thanks!!!

[Spinners 15,986]

I think its kg but for fuel it's virtually the same as litres (a litre of water is 1kg).

[+Gepard 11,301]

fuel in kilogram

1 litre AvGas=0.72 kg                 

1 litre JP-4 jet fuel = 0.82 kg

[+russouk2004 6,958]

Yeah KG as cockpit gauges read KG burned \ used 

[Wrench 9,848]

you'd think that after all these years, i'd know (ie: remember) this stuff .... i think the heat here is frying my brain (set a new record high temp here in LA yesterday -- 121 F!!!

[Wilches 1,172]

2 hours ago, Gepard said:

fuel in kilogram

1 litre AvGas=0.72 kg                 

1 litre JP-4 jet fuel = 0.82 kg

That's why in aviation the fuel is measured in kilos not in litres.

[+streakeagle 871]

The problem is that fuel tanks have capacities determined by volume: gallons or liters, while aircraft performance depends on weight. So, you really need to know both the size  of the tanks in terms of volume and the type of fuel to know its associated density. What I don't know is how an aircraft's display/indicator for fuel works when it displays weight. It wouldn't make sense for it to be using a float to determine tank level. It would make sense to have a flow meter that is calibrated for mass flow, but that requires assuming the density of the fuel and in my experience in industrial controls, flow meters aren't particularly accurate with errors of 2 to 5% being common no matter what the manufacturer's brochure claims.

[+Crusader 2,101]

We have two values int he data for external (drop) tanks:

Mass= - the total weight of the tank itself and the fuel content

MaxFuelAmount= - the fuel content in kg

 

There are still many droptanks around which have a Mass value less than the MaxFuelAmount - thats an error.

If the weight of the empty tank is not known, then a rule of thumb is to assume 10% of the fuel content for the weight of the empty tank.

[Wrench 9,848]

well, these are all internals 

gallons, moving aft

377  189  223

and two 44 gal wing tanks

doing the online conversion thingy ... this is what I got

Quote

// Fuel Tanks ---------------------------------------------------------

/fwd//

[FuselageFuelCell1]
SystemType=FUEL_TANK
FuelTankID=1
MaxFuelAmount=1427.0
SelfHealing=TRUE
FireSuppression=TRUE
MinExtentPosition=-0.3865,0.9416,0.9672
MaxExtentPosition= 0.3255,-2.3569,-0.3843
HasArmor=TRUE
ArmorMaterial=STEEL
Armor[TOP].Thickness=5
Armor[BOTTOM].Thickness=5
Armor

.Thickness=5

Armor

.Thickness=5

Armor[FRONT].Thickness=5
Armor[REAR].Thickness=5

//center//

[FuselageFuelCell2]
SystemType=FUEL_TANK
FuelTankID=2
MaxFuelAmount=715.0
SelfHealing=TRUE
FireSuppression=TRUE
MinExtentPosition=-1.3287,0.7112,-0.0235
MaxExtentPosition= -4.9720,-0.3566,0.2693
HasArmor=TRUE
ArmorMaterial=STEEL
Armor[TOP].Thickness=5
Armor[BOTTOM].Thickness=5
Armor

.Thickness=5
Armor

.Thickness=5
Armor[FRONT].Thickness=5
Armor[REAR].Thickness=5

/aft//

[FuselageFuelCell3]
SystemType=FUEL_TANK
FuelTankID=3
MaxFuelAmount=844
SelfHealing=TRUE
FireSuppression=TRUE
MinExtentPosition= 1.4980,0.6275,-0.0910
MaxExtentPosition= 5.1414,-0.2938,0.2242
HasArmor=TRUE
ArmorMaterial=STEEL
Armor[TOP].Thickness=5
Armor[BOTTOM].Thickness=5
Armor

.Thickness=5
Armor

.Thickness=5
Armor[FRONT].Thickness=5
Armor[REAR].Thickness=5

[LeftWingFuelCell]
SystemType=FUEL_TANK
FuelTankID=4
MaxFuelAmount=166.0
SelfHealing=TRUE
FireSuppression=TRUE
MinExtentPosition=-0.70,-1.03,-0.68
MaxExtentPosition=-1.95,-0.20,-0.40
HasArmor=TRUE
ArmorMaterial=STEEL
Armor[REAR].Thickness=2
Armor

.Thickness=2
Armor

.Thickness=2
Armor[TOP].Thickness=2
Armor[BOTTOM].Thickness=2

[RightWingFuelCell]
SystemType=FUEL_TANK
FuelTankID=5
MaxFuelAmount=166.0
SelfHealing=TRUE
FireSuppression=TRUE
MinExtentPosition= 0.70,-1.03,-0.68
MaxExtentPosition= 1.95,-0.20,-0.40
HasArmor=TRUE
ArmorMaterial=STEEL
Armor[Front].Thickness=2
Armor[REAR].Thickness=2
Armor

.Thickness=2
Armor

.Thickness=2
Armor[TOP].Thickness=2
Armor[BOTTOM].Thickness=2

and to Streakeagle -- this particular 1948 era bird actually did use floats in each tank (have the pilots manual)

[+russouk2004 6,958]

Windows 10 calculator does same....

[Wrench 9,848]

excepting that i'm still on Winge7  

[+Menrva 4,200]

1 hour ago, Wrench said:

excepting that i'm still on Winge7  

You might find the following links useful.

myE6B Fuel Conversion: https://mye6b.com/Fuel/

Jet Fuel from Gallons to Pounds Calculator: https://jscalc.io/embed/oyHJrYooUr1wDQPb

Moreover, if you know a specific fuel type used by a given aircraft, and use the density mean value, you can obtain much more accurate values in-game. For instance, for the yet to be released Raptor add-on, I was able to reproduce all internal fuel tanks properly, and together with external ones, a proper 26,000 lb (slightly more) are shown by the digital counter in the cockpit. For instance, the Raptor uses JP-8, and the density mean value of JP-8 should be around 0.8075 kg/L (https://www.repsol.com/en/products-and-services/aviation/jp-8/index.cshtml).

Edited September 8, 2020 by Menrva