Treibstoffverbrauch

[ralfpeterfischer 0]

Ich fliege mit allen möglichen Flugzeugen. Pay,- und Freeware. Gerade aber bei den Freeware - Fliegern bekomme ich fast immer ein Treibstoff - Problem. Ich stelle erst den Flugplan auf und suche dann 

ein passendes Flugzeug für die Entfernung aus. Dabei richte ich ich nach Reichweiten - Angaben verschiedenster Quellen. Nun passiert es aber oft. dass ich für eine Strecke von zum Beispiel von 1600 nm einen Flieger

einen Flieger mit der Reichweite von 3000 nm auswähle, dem aber, vollgetankt gestartet wohlgemerkt, schon nach der Hälfte der Strecke, also ca 800 nm der Sprit ausgeht.

Das geht ja bei bei den widrigsten Umständen wohl kaum.

Also muss in der Airplane- cfg irgend ein Parameter zu finden sein, den man ändern müsste.

Kann mir jemand sagen, wo?

Gruß Peter Fischer

English translation...

I fly all kinds of airplanes. Pay, - and freeware. But especially with the freeware planes, I almost always get a fuel problem. I first set up the flight plan and then search a suitable plane for the distance. In doing so, I am based on ranges - information from a wide variety of sources.

But now it happens often. that I take a plane for a distance of, for example, 1600 nm Select a plane with a range of 3000 nm, but after starting with a full tank, mind you, already runs out of fuel after half the distance, i.e. approx. 800 nm. That is hardly possible in the most adverse circumstances.

So there must be some parameter in the aircraft cfg that needs to be changed. Can someone tell me where? greeting

 

Edited December 4, 2021 by Ray Proudfoot
Added English translation.

[Ray Proudfoot 8,526]

@ralfpeterfischer, we politely request all posts are in English. I have converted your post and added an English translation.

[F737MAX 4,721]

18 hours ago, ralfpeterfischer said:

I fly all kinds of airplanes. Pay, - and freeware. But especially with the freeware planes, I almost always get a fuel problem. I first set up the flight plan and then search a suitable plane for the distance. In doing so, I am based on ranges - information from a wide variety of sources.
But now it happens often. that I take a plane for a distance of, for example, 1600 nm Select a plane with a range of 3000 nm, but after starting with a full tank, mind you, already runs out of fuel after half the distance, i.e. approx. 800 nm. That is hardly possible in the most adverse circumstances.
So there must be some parameter in the aircraft cfg that needs to be changed. Can someone tell me where? greeting

Which freeware aircraft are you using?
Freeware aircraft are never the most accurate, especially when compared to payware ones.

Given that you have such a big disparity in fuel usage, it would be helpful to know how you fly them also.

• Are you reaching an appropriate cruise altitude?
• Have you fully retracted the flaps, spoilers and gear before reaching 3,000 feet?
• What is your rate of climb in feet per minute?

 

The fuel parameters can be changed in aircraft.cfg, but it can become incredibly unrealistic if you change the values too much from the default numbers.
 

Quote

fuel_flow_scalar

Scalar for modifying the fuel flow required by the engine(s). A value of less than 1.0 causes a slower fuel consumption for a given power setting, a value greater than 1.0 causes the aircraft to burn more fuel for a given power setting.

Mooney Bravo ( fuel_flow_scalar = 1.0 )

Source: https://www.prepar3d.com/SDKv4/sdk/simulation_objects/aircraft_configuration_files.html

[ralfpeterfischer 0]

come back to the subject again.
Yesterday I made another flight with the HS734, on a distance of 390 nm. I flew with a full tank and at 200 nm the tanks were empty. And that's how it works with the standard or freeware planes for almost all flights. Payware or the Mooney, on the other hand, have a realistic range. That's why I want to change the consumption so that you can choose the planes based on the real data of the range according to the planned route. So if I want to fly 1000nm, I look for a plane that has at least 1500nm range in real life. Lufthansa doesn't take a 777-200 from Munich to Hamburg just to make sure there's enough fuel.
For example, here is the fuel section of the HS734:
 [fuel]
fuel_type =2
number_of_tank_selectors =2
electric_pump =1
LeftMain = 1000, -12000, -3000, 865000, 4000
RightMain = 1000, 12000, -3000, 865000, 4000
fuel_dump_rate=0.02600
electric_pump = 1
anemometer_pump=0
manual_pump=0
engine_driven_pump=0

How can I increase the range?

Thank you Peter Fisher

[F737MAX 4,721]

9 minutes ago, ralfpeterfischer said:

LeftMain = 1000, -12000, -3000, 865000, 4000
RightMain = 1000, 12000, -3000, 865000, 4000

These values look very wrong to me.

The 1000, -12000, -3000 refer to the position of your fuel tank on your aircraft in relation to the datum reference point.
Most of the time they tanks should be located within 100 feet of the centre of the aircraft. Your example has them at 1000 feet, 12000 feet and 3000 feet away from the centre.

Additionally, the fuel tank capacity in your example is 865000 US gallons (3932368 litres!!!!), with 4000 gallons defined as 'unusable'. If you fill the tanks to 100%, I do not understand how you could take off due to the weight of all that fuel.

 

The following information comes from the Prepar3D website, the same link I shared with you last month.

Quote

[fuel]

 

This section defines the characteristics of the fuel system, including the tanks, fuel type, and the number of fuel selectors. The number of fuel selectors is intended to match the number of visual selectors on the instrument panel.

Property	Description	Examples
center1 center2 center3 leftmain leftaux lefttip rightmain rightaux righttip external1 external2	Position of the tank relative to datum reference point, followed by the usable and unusable capacities of the tanks, in gallons.	Bombardier CRJ 700( Center1 = -48.7, 0.0, -4.0, 982.0, 0.0 ) DeHavilland Beaver DHC2( Center3=-10.600000,0.000000,-1.900000,25.000000,0.000000 ) Mooney Bravo( RightMain = -4.1, 7.9, -0.8, 47.5, 3.0 ) Maule M7 260C( LeftAux = -2.24, -11.4, 2.40, 15.0, 0.00 )
fuel_type	One of: 1 = Avgas 2 = JetA	Mooney Bravo( fuel_type = 1 ) Bombardier CRJ 700( fuel_type = 2 )
number_of_tank_selectors	Number of fuel tank selectors (maximum 4 and should be less than or equal to the number of engines).	Mooney Bravo( number_of_tank_selectors = 1 ) Bombardier CRJ 700( number_of_tank_selectors = 1 )
electric_pump	Boolean that sets whether an electric boost pump is available, 0 = FALSE, 1 = TRUE.	Mooney Bravo( electric_pump = 1 )
fuel_dump_rate	Percent of fuel that can be dumped per second.
engine_driven_pump	Set to 0 if the pump is engine driven (1 is the default).	DeHavilland Beaver DHC2( engine_driven_pump=1 )
manual_pump	Set to 1 if there is a manual transfer pump.	DeHavilland Beaver DHC2( manual_transfer_pump=1 )
anemometer_pump	Set to 1 if there is an anemometer pump.
default_leak_rate_gps	Allows overriding the default maximum rate (gallons per second) when a fuel leak is selected.	default_leak_rate_gps = 0.2

I would expect to see numbers that look more like these examples:
 

Spoiler

Freeware Project Airbus A380:

[fuel]
fuel_type            = 2
number_of_tank_selectors    = 4
electric_pump            = 0

Lefttip        = -25.00, -100.00, 2.00,  2731.54, 0.00
LeftAux        =   3.00,  -55.00, 1.00, 16931.58, 0.00
LeftMain    =  25.00,  -20.00, 0.00, 19942.61, 0.00
Center3        = -85.00,    0.00, 8.00,  6260.35, 0.00
RightMain    =  25.00,   20.00, 0.00, 19942.61, 0.00
RightAux    =   3.00,   55.00, 1.00, 16931.58, 0.00
Righttip    = -25.00,  100.00, 2.00,  2731.54, 0.00

 

Spoiler

PMDG 737-800:

[fuel]
Center1=  -1.884,   0.000, -1.800, 4299.000, 0.000
LeftMain= -9.110, -16.500,  1.600, 1288.000, 0.000
RightMain=-9.110,  16.500,  1.600, 1288.000, 0.000
fuel_type=2.000000
number_of_tank_selectors=1
electric_pump = 1
fuel_dump_rate = 0.0

 

Spoiler

P3D default C-130J:

[fuel]
fuel_type=2
number_of_tank_selectors=4
electric_pump=1
fuel_dump_rate=0.00085
engine_driven_pump=0
External1=  -0.75, -25.49,  -7.03,  1400.00,   10   // EXT Left
LeftAux=    -0.75, -25.49,  -2.03,   910.00,    9   // Aux Left
LeftTip=     0.00, -16.86,  -2.09,  1350.00,   10   // Tank 1    
Center2=    13.64,   0.00,  -4.19,  1240.00,   10   // Tank 2    
Center3=   -20.95,   0.00,  -4.19,  1240.00,   10   // Tank 3    
RightTip=    0.00,  16.86,  -2.09,  1350.00,   10   // Tank 4   
RightAux=   -0.75,  25.49,  -2.03,   910.00,    9   // Aux Right
External2=  -0.75,  25.49,  -7.03,  1400.00,   10   // Ext Right

 

I don't know which aircraft you are referring to when you say you fly with the 'HS734'. However, it either has terrible data, or you have changed too many values in the aircraft.cfg and made the aircraft useless.
Either download the aircraft again to get the original aircraft.cfg back (but remove the aircraft.cfg file you are currently using in the first instance) or use better freeware aircraft.

Once again, I don't know how you fly your aircraft. If you try to fly long distances without reaching 25,000 feet or higher, don't retract the flaps, landing gear, or spoilers fully, then you burn fuel at a much faster rate and fail to reach your destination.

[ralfpeterfischer 0]

 

That was the HS734 cfg original

The numbers are just copied from the Airplane cfg without changing anything. And I didn't build the plane. That's why I'm wondering how the numbers in the cfg come about and how you can put them into a real state. Incidentally, this is the case with many of the add-on aircraft. Only the payware PMDG and QW planes have a realistic range.

Peter