AIR files and Drop Tanks

[_486_Col_Wolf]

Does anyone know which AIR file entry determines the number of drop tanks to release? One of my A/C drops only the left tank but if I switch the AIR file with a known and working 2 drop tank A/C, then they both drop. This leads me to believe the AIR file controls it.

[Ravenna]

I always assumed that the release of drop tanks worked from the hardpoint entries in the DP file, set up so that the second drop tank could drop in sequence after the first tank released. So, mount.10=drop tank, 1, 11
mount.11=drop tank, 1, -1
If there were, then 3 drop tanks ( one under the fuselage and one under each wing) the sequencing of the drop could be fuselage tank followed by wing tanks; mount.12 being the same as mount 10 in this example if mount 11 is positioned under the fuselage.

[Allen]

The air file must have drop tank record for every drop tank. If the air file only list 1 drop tank but DP has 2 drop tanks the game will only drop 1 tank.

[_486_Col_Wolf]

Allen,
That's what I assume considering changing the AIR file to a known working one corrects the problem. I've tried changing the DP file, entries withing the DP file etc... but no joy. It has got to be and entry in the AIR file. But, which one? None of them say anything about drop tank and there are so many listed as "Unknown"...

[The B24 Guy]

Here is the info I have.

Here are the TANK ID'S displayed by the dump tank gauge and the corresponding air file section number for each tank:

"Ctr 1" = section 531 - Center Tank 1
"Wng L" = section 525 - Left Wing Tank
"Wng R" = section 526 - Right Wing Tank
"Aux L" = section 527 - Left Aux Tank
"Aux R" = section 528 - Right Aux Tank
"Tip L" = section 529 - Left Tip Tank
"Tip R" = section 530 - Right Tip Tank
"Ctr 2" = section 532 - Center Tank 2
"Ctr 3" = section 533 - Center Tank 3
"L Drop = section 534 - Left Drop Tank
"R Drop = section 535 - Right Drop Tank

Fuel tank usage in CFS 2 with Auto Fuel Management turned ON:
The fuel tanks are organized into two groups of tanks: center tanks and wing tanks. Fuel is burned from both groups simultaneously; i.e., if there is fuel in a center tank and fuel in a wing tank, then fuel is drawn from both tanks containing fuel.
In addition, the wing tanks are paired. All fuel from both wing tanks in a pair is burned before fuel is burned from the next pair.
In the center tank group, fuel is burned first from Center Tank 3, then Center Tank 2, and last from Center Tank 1.
In the wing tank group, fuel is burned first from the Left and Right Aux Tanks, then from the Left and Right Wing Tanks. If Auto Fuel Management is turned on, fuel in the Tip Tanks will not be used.

Hope this helps,
B24Guy

[Shadow Wolf 07]

I always assumed that the release of drop tanks worked from the hardpoint entries in the DP file, set up so that the second drop tank could drop in sequence after the first tank released. So, mount.10=drop tank, 1, 11
mount.11=drop tank, 1, -1
If there were, then 3 drop tanks ( one under the fuselage and one under each wing) the sequencing of the drop could be fuselage tank followed by wing tanks; mount.12 being the same as mount 10 in this example if mount 11 is positioned under the fuselage.

I agree with the above. I always saw the drop tanks as "Ordinance" and in the keyboard, by CFS2 default they "armed" when you cycle through ordinance and then released selected ordinance - individually. When you have more than one drop tank, you have to cycle to the next to release it, just like you do when you have mixed loads, like bombs and rockets. I have done that with the F4F-4 Wildcat, cycling and releasing in quick sequence.

The result appears in this old screenshot as a staggered release, but both released fine, with very little spacing between them (too much here because I was slow to cycle and hit the pause key to take the screen shot). As I recall, there is a release drop tank selection in the CFS2 default keyboard menu. Or am I wrong? I haven't looked in there in a long time... And I'm too lazy to look now - but if so, activating that key might solve the problem.

[Oglivie]

The maximum number of drop tanks allowed in the air file is two. If the DP file has only one tank and two are set in the air file, all the fuel in the air file left and right drop tank is carried by the aircraft. If the tank is dropped though only one of the drop tank fuel quantity is release in the air file, while the other air file tank quantity remains since only one tank is dropped in the DP. For two drop tanks in the DP to work, both left and right drop tanks have to be in the air file. If a drop tank is missing in the air file, copy the correct section from an existing air file that has the drop tank and past it into the air file you want to use and adjust the entries.

There can be more than two tanks carried at one time and the best way for this is to have the extra tanks configured in the weapons scenery bgl file. For instance for four tanks, two tanks are configured in the bgl. Then the two tanks can be set as one tank in the DP and air file for each side of the aircraft. This is a work around for the air file only being able to be set for two tanks.

There can be two configurations for drop tanks in the DP for one drop tank and a two drop tank payload. This is best set with a bgl file that is for an invisible tank that can be released if only one tank is chosen as payload. Both drop tank lateral positions in the air file should be set to 0 (zero) to avoid lateral out of balance.

This is a sample of a config for a P-47 that has two drop tank payload options in the DP, either one 150 gallon tank under the fuselage or two 108 gallons tanks under the wings. The problem is though is that the lateral position of the left and right drop tanks in the air file should be set to zero to avoid an out of balance condition if the fuselage drop tank option is chosen. This being the case, it may not be desirable to have this configuration as the wing tanks will not have an accurate weight position in the air file. It is just a work around two have more than one payload option to choose from for the drop tanks.

Samples:

DP mount.0 is set for the invisible drop tank bgl. It is offset slightly to the right so that the right drop tank fuel quantity in the air file is released so only the fuel quantity in the left drop tank is left for the center 150 gallon drop tank.

[HARDPOINTS]
mount.0=0.000001,0,0
//Triple Rocket Tube Launchers
mount.1=-3.0936,-0.4685,0.0751
mount.2=3.0936,-0.4685,0.0751
//4.5-inch Rockets
mount.3=-3.0936,-0.61,0.0351
mount.4=3.0936,-0.61,0.0351
mount.5=-3.15,-0.72,0.0351
mount.6=3.15,-0.72,0.0351
mount.7=-3.03,-0.72,0.0351
mount.8=3.03,-0.72,0.0351
//
mount.9=0,-1.285,0.27
mount.10=0,-1.285,0.27
mount.11=-3.57,-0.705,0
mount.12=3.57,-0.705,0
mount.13=-3.57,-0.725,0
mount.14=3.57,-0.725,0
mount.15=-0.000001,-1.275,0.2
mount.16=-3.57,-0.652,-0.12
mount.17=3.57,-0.652,-0.12

[PAYLOADS]
payload.0=%payload_name.0%
payload.1=%payload_name.1%
payload.2=%payload_name.2%
payload.3=%payload_name.3%
payload.4=%payload_name.4%
payload.5=%payload_name.5%
payload.6=%payload_name.6%
payload.7=%payload_name.7%
payload.8=%payload_name.8%

[PAYLOAD.0]
; Payload = Guns Only

[PAYLOAD.1]
; Payload = Long Range - 150 gallons
mount.0=Release_DT_for_correct_fuel, 1, -1
mount.9=wep_pylon_us_cl, 1, -1
mount.15=wep_P47_150gal_drop, 1, -1

[PAYLOAD.2]
; Payload = Extra Long Range - 2 x 108 gallons
mount.16=wep_us_108gal_tank, 1, -1
mount.17=wep_us_108gal_tank, 1, 16

(left empty to skip to payload names in DP)

"payload_name.0"=Guns Only
"payload_name.1"=Guns Only Long Range*
"payload_name.2"=Guns Only Extra Long Range

The air file left tank is set for the 150 gallon for the center tank. The right tank is set for 66 gallons to add 66 to 150 giving total fuel of 216 gallons for two tanks (2 x 108 = 216). Model name option for invisible drop tank: "Release_DT_for_correct_fuel"=*Release this tank for correct fuel qty.

[Allen]

Allen,
That's what I assume considering changing the AIR file to a known working one corrects the problem. I've tried changing the DP file, entries withing the DP file etc... but no joy. It has got to be and entry in the AIR file. But, which one? None of them say anything about drop tank and there are so many listed as "Unknown"...

Sounds like your using and quite old version of AirEd. Grab this version.

http://www.sim-outhouse.com/sohforum...49&linkid=3142

Drop tanks are found at 534 *Fuel External 1 Tank and 535 *Fuel External 2 Tank.

[_486_Col_Wolf]

I have two tanks in the DP but when "drop all tanks" key is triggered, only one drops (left). Even if I cycle through them as ordinance and try to drop one at a time only one drops (left) It was only after I changed to a known good AIR file in which both tanks from that A/C drop that the new A/C also dropped both tanks. since the original DP file was not changed, the AIR file is the only thing that can make the difference.

[Allen]

Your going to need to copy and pasted 535 *Fuel External 2 Tank from a air file that has 535 *Fuel External 2 Tank into your non working air file.

You need to start 2 of AirEd 1.52. The first will have the non working air file and the other will be of an aircraft that has 2 working drop tanks like F4F4 Wildcat.

In the F4F4 Wildcat find the 535 *Fuel External 2 Tank and right click on it and Copy to Clipboard. Now in the other AirEd that has the non working air file open, right click on any of the records and used Paste from Clipboard.

Now a 535 *Fuel External 2 Tank should be in the non working air file. Now you need to edit the 535 *Fuel External 2 Tank. The 534 *Fuel External 1 Tank should tell you just about everything that you need to copy to 535 *Fuel External 2 Tank. Just swap the left/right offset and edit the fuel tank number so that is next in line.

[_486_Col_Wolf]

Thanks Allen! I kinda figured it was the AIR file. Now as soon as my back gets better and I can climb into my simpit, I'll give it a try.

[_486_Col_Wolf]

Allen,
I made the changed to the AIR file and all is working now. One thing however, if you label the tanks in the AIR file incorrectly your fuel selector may work different ie... if the tank is labeled right wing your fuel selector will not work if it says Main or Res.

[Allen]

Fuel selector gauges are programmed to worth with only certain tanks. This mean you may need to change Fuel selector gauges and/or tanks in the air file around.