Gauges for FWD and AFT AUX Fuel Tanks on B727-200

I have added tanks to the aircraft.cfg for Optional Tank 1 (FWD AUX) and Optional Tank 2 (AFT AUX) and positioned them where they belong in the fwd and aft cargo holds of a B727-200 Advanced (Option 2).

 

For CG purposes I've had to split each of the two Optional tanks into two equal parts and to pair the two parts of each Optional tank in an unconventional way (see attachment 1).

 

This tank setup works very well in flight, achieving the desired movement of the CG with minimal fuel management (see attachment 3), but there are no FWD AUX and/or AFT AUX quantity gauges that work with this unconventional setup and, as it appears to be the best FS tank setup to use for installing these two Optional tanks, I'm curious to know if it is possible to create the required gauges.

 

Is it possible to create a single analog and/or digital FWD AUX fuel quantity gauge calibrated to max 6,000 lb at 6.7 lb/usg which displays the combined total in FS tanks LeftTip + RightAux (combined max 810 usg/5,427 lb) and a single analog and/or digital AFT AUX fuel quantity gauge also calibrated to max 6,000 lb at 6.7 lb/usg which displays the combined total in FS tanks LeftAux + RightTip (combined max 860 usg/5,762 lb), both gauges for use in FSX ?

 

NOTE: This tank setup, and the gauges I'm asking about above, cannot be used for Standard Tanks 1,2,3 + only Optional Tank 2 (AFT AUX) as it requires a different FS tank pairing (LeftAux + RightAux) for Optional Tank 2 (see attachment 2).

 

Is it therefore also possible to create another single analog and/or digital AFT AUX fuel quantity gauge again calibrated to max 6,000 lb at 6.7 lb/usg which displays the combined total in FS tanks LeftAux + RightAux (combined max 860 usg/5,762 lb). To go with this another single analog and/or digital FWD AUX fuel quantity gauge would be required also calibrated to max 6,000 lb at 6.7 lb/usg which displays the quantity in FS tank LeftTip only (max 810 usg/5,427 lb).

 

WARNING: Adding Optional fuel tanks to B727-200 aircraft, if not done correctly, may have a devastating effect on the aircraft's on-ground stability and flight dynamics. Simply adding fuel to existing tanks 1, 2 and 3 is not an option I would suggest or recommend.

 

I'm not asking anyone to create the gauges for me, I'm just asking if it can be done.

There are a lot of variables for fuel quantity. A:Variables.

here's a list.

FUEL TANK CENTER LEVEL

FUEL TANK CENTER2 LEVEL

FUEL TANK CENTER3 LEVEL

FUEL TANK LEFT MAIN LEVEL

FUEL TANK LEFT AUX LEVEL

FUEL TANK LEFT TIP LEVEL

FUEL TANK RIGHT MAIN LEVEL

FUEL TANK RIGHT AUX LEVEL

FUEL TANK RIGHT TIP LEVEL

FUEL TANK EXTERNAL1 LEVEL

FUEL TANK EXTERNAL2 LEVEL

 

(A:FUEL TANK EXTERNAL2 LEVEL, percent) gives as result the current percentage in external tank 2.

 

All of these also exist as quantity.

(A:FUEL TANK EXTERNAL2 QUANTITY, pounds) gives the amount in pounds.

(A:FUEL TANK EXTERNAL2 CAPACITY, Gallons) gives the capacity in gallons.

 

But there's no "forward left auxiliary" in there.

 

How did you edit these fuel tanks? are you creating an aircraft 3d model, or are you editing an existing aircraft.cfg file?

and, this extra tank you added (forward left auxiliary) does in show (with that name etc) in the "fuel and payload menu"? Or is the quantity you added shown as added fuel lbs in the center tank instead?

il88pp already gave you the list of available fuel level variables. You can create a gauge which will display the fuel remaining in any combination of those tanks.

"You can create a gauge which will display the fuel remaining in any combination of those tanks."

 

Thanks Tom. That's all I wanted to know.

I've attached two slightly different fuel management plans that I use when all three Optional Fuel Tanks are installed.

 

The B727 has three engines fed at any one time by three fuel tanks, one of which is Center1. If the aircraft.cfg shows number_of_tank_selectors=3 then FS appears to use fuel in 9 lb blocks, the position of the Boost Pumps and/or Crossfeed Valves or the Fuel Selector Switch determining how much of that 9 lb block is extracted by FS from each of the three tanks.

 

When I use the CS PANEL (where the fuel flow per tank is determined by the Boost Pump positions) I get L+C+R fuel flow figures of 1+7+1 in the fuel management phase of the flight. I get the same figures using the Fuel Selector Switch (from an L1049G panel) I installed on the RP PANEL (see revised attachment 3 of the original post).

 

When I use the TR PANEL (where the fuel flow per tank is determined by the Crossfeed Valve positions) I get L+C+R fuel flow figures of 2+5+2 in the fuel management phase of the flight.

 

I can only assume these L+C+R differences are the result of the way the relevant gauges have been programmed by whoever created the gauges ?

 

Knowing what the L+C+R figures are for the panel being used is essential for creating accurate fuel management plans when Optional tanks are used.

 

Also attached is a list of the hold cargo positions which are relevant to the Optional Fuel Tank installation process.

 

To answer an earlier question. I'm just an FS user, with a preference for the Boeing 727, who knows nothing about FS aircraft model or panel development. Tolerance of my ignorance would therefore be appreciated.