Fueling the discussion...

[hubbabubba]

FINAL OBSERVATIONS

As mentioned, I tried Hurricane and FW fuel switches together. The result was that I had almost entire control on central tanks and on lateral tanks groups, I could choose center #1-2-3 and right or left tanks, but always emptying auxiliary before main tanks. This method can have its drawbacks though. One of them is that, while clicking on one gauge, the other will visually switch too, giving false information. For example, if I switch the FW gauge to center #2, the Hurricane gauge will point to starboard tanks. This may be confusing, especially in the heat of the action. You must always remember that only the gauge you actually clicked on is showing the real tank(s) being emptied.

If you have observed carefully, you will note that no gauges, FS98 or CFS1 style, is capable of tapping both right and left tanks at the same time. This is quite unfortunate as many a/c would manage fuel that way, if only to keep proper balance. Only at start-up do both sides are being emptied simultaneously. I don't know if such a gauge is feasible, but why not? After all, it is doing it on start.

Curious to know what was done in FS2000 Pro, I installed mine just to have a look at the "pristine" gauge folder. The only fuel switches I found there are the CFS1 "cluster gauges"! There is not even one FS2000 specific cluster gauge! We can't say that M$ went to great efforts for that release. Only in CFS2 would they create new original fuel switches.

While we are waiting for new CFS1 fuel switches (yeah...), modelers will have to "make do" with what's at hand. For example, a "center" gauge doesn't have to be on the center line and a left tank can be dead center. We should think out of the box and not necessarily follow the labeling of the AIR files.

 

[Ivan]

Hi Hubbabubba,

Next question that I can see would be: How well do the available fuel gauges cover the possibilities that we see in various aircraft? As you pointed out, it would be cool to have a switch setting that would use both Left and Right Main tanks at the same time, but is there an aircraft that has this arrangement?

I can tell you that for the P-40 series of aircraft, the FW 190 gauge works well enough to properly control a similar arrangement of tanks. The markings are not useful, but I had a workaround for that as I will show in a screenshot later. It may not be elegant, but it isn't bad IMHO.

For the F4U-1D Corsair, there is only a single internal tank with drop tanks that we do not represent, so NO gauge is sufficient. BTW, To represent Drop Tanks, can we have left and right tanks with fuel dump switch to represent salvoing the tanks before combat?

For the F4U-1A Corsair which has no drop tanks but has a couple unarmoured outboard wing tanks, I just used the P-51D fuel switch. Seems to work though I would like to be able to choose NOT to fill those tanks for combat missions because they were only intended for ferry flights.

For a Me 109 with a drop tank, we could use the Fuselage Auxiliary tank as the drop tank and a fuel dump switch for the aux tank. This plane didn't have a fuel switch to select drop tanks because air pressure was used to push fuel into the main (and only) tank which the engine used as its only supply.

For the SBD Dauntless, the outboard wing tanks can be set as aux tanks and do not need a separate selection because they will empty as the left and right mains are selected.

For the Ki-61 Hien, A6M Reisen and J2M Raiden, the P-51D fuel selector works to select Left, Right, and Fuselage tanks.

For the Fokker Eindecker, no switch is necessary because although the pilot has to pump fuel from the "Main" tank to the one that the engine uses, we can just call the engine's tank as the Main tank and the real "Main" tank becomes the Auxiliary tank. Fuel use will be in the proper order.

I was reading that the Hawker Sea Fury had a peculiar arrangement of tanks similar to the Germans in which some tanks only acted to supply others. Need to go back and read that again.

What is the next step? Perhaps reviewing the fuel quantity gauges to figure out which to use?

- Ivan.

 

[Ivan]

Hello Hubbabubba, et al.

Years and years after the last post, I am about to revive another old thread, but I believe it makes sense to do so rather than start another thread on the same subject when Hubbabubba has presented a great amount of information on the subject.

First I would like to answer my question about whether or not any real aeroplane actually draws from both Wing Tanks at the same time.
Note that since the prior post in this thread, I have completed and released a Macchi C.202 Folgore.
It actually does have two small Wing Tanks that are not individually selected.
Another aeroplane that has been the subject of a little research during this time is the Nakajima Ki 43 Hayabusa.
It, in fact has two pairs of Wing Tanks and ONLY draws from them in matched pairs.

There is a minor factor that seems to have been hidden by the testing protocol used for the Fuel Switching Gauges:
This is one I should have noticed years ago, but only noticed when I found this thread in a Web Search a couple months ago and re-read it from the start.
In the Check Lists for my P-40 series, the instructions call for switching to the Fuselage Tank before starting the engine.
Now this would make absolutely no sense if the fuel switch setting were over-ridden by the engine start process, but it is not.
The selection remains even after engine start.
This in itself is no proof because even without a selector, the Fuselage Tank would be drawn from first until it is done, but one can confirm with stock aircraft that the selector setting is NOT over-ridden at engine start.

To confirm this, I used the stock P-51D which has Left Main, Right Main, and Center 1 Fuel tanks.
If the selector is not used, the default is to draw from all three tanks as stated.
If the 'E' key is used to start the engine, then the Fuel Selector is set to the Center position and all three tanks are used.
However....
If the Magneto, and Starter switches are used to start the engine, then the Fuel Selector setting does not change and fuel is drawn ONLY from whichever tank is selected.

The obvious question would be: Why am I resurrecting this old thread and why was I searching on the Internet for Fuel Switching?
The reason is simple: I have been working on Gauges for Multi Engine projects and have finally had some minor successes.
With the basic gauges out of the way, I am now looking toward programming some of the other gauges (such as Fuel Selectors) that are not to be found among the available stock gauges.

For both the P-38 Lightning and the B-25 Mitchell, the default Fuel use can be used to mimic the recommended fuel selection order even without gauges.
Note that with Fuel Selector Gauges for a Twin Engine Aeroplane, not only should there be a tank selector for each engine (two or three per side) but a Cross Feed Switch should also be present to use the remaining fuel for a non functioning engine.

So even if the Lightning and Mitchell do not need these gauges, perhaps I can address issues to be found in some of my other projects.

- Ivan.

 

[papingo]

good thinking......

Hubba's idea of filling up all tanks with ten galls. of
fuel and observing the results.....good thinking!
anyone else doing interesting stuff like this

>>papingo

 

[Ivan]

Hello Papingo,

Glad to see you here.

I think there are a couple interesting subjects being discussed at the moment, just not in this particular thread.
I bumped it for a reason. There will be some work done in this area soon, but first I just need to figure out how to access all the fuel tanks that are available in CFS. The information I have available does not make it very clear how to do it.
The default non-selected order that fuel tanks are expended is nice to know, but wouldn't it be even better if we could build a fuel selector to affect that order and not just know how it behaves if we CAN'T affect it?

That was where I was headed before the recent diversion to a much older subject which I am still working on for now.

Take Care.
- Ivan.

 

[Ivan]

There is a minor factor that seems to have been hidden by the testing protocol used for the Fuel Switching Gauges:
This is one I should have noticed years ago, but only noticed when I found this thread in a Web Search a couple months ago and re-read it from the start.
In the Check Lists for my P-40 series, the instructions call for switching to the Fuselage Tank before starting the engine.
Now this would make absolutely no sense if the fuel switch setting were over-ridden by the engine start process, but it is not.
The selection remains even after engine start.
This in itself is no proof because even without a selector, the Fuselage Tank would be drawn from first until it is done, but one can confirm with stock aircraft that the selector setting is NOT over-ridden at engine start.

To confirm this, I used the stock P-51D which has Left Main, Right Main, and Center 1 Fuel tanks.
If the selector is not used, the default is to draw from all three tanks as stated.
If the 'E' key is used to start the engine, then the Fuel Selector is set to the Center position and all three tanks are used.
However....
If the Magneto, and Starter switches are used to start the engine, then the Fuel Selector setting does not change and fuel is drawn ONLY from whichever tank is selected.

Yet another update:
The 'E' key does selects all available tank groups, resets mixture, and turns on both magnetos before starting the engine.....
....on a CFS AIR File.

With the current Kawasaki Ki 61 project, I have also been looking around and experimenting with other related aeroplanes on my game machine.
One of them is a very nice Kawasaki Ki-100 model that happens to have a FS98 AIR File.
On this aeroplane, the 'E' key does NOT select all available fuel tank groups from what I can tell so apparently this process does not work the same with a FS98 Flight Model used in Combat Flight Simulator....

- Ivan.

 

[Ivan]

My First Custom Fuel Selector

About a year and a half after the last post, and with the release of my rework of Eric Johnson's P-39D Airacobra, I have finally finished my first custom Fuel Selector.

The P-39 Airacobra only has a single fuel tank in each Wing Root.
There is no CFS stock Fuel Selector which only has Left and Right Fuel Tanks.
While it is possible to arrange the Fuel Tanks in the AIR file so that the fuel selector from the stock P47D can be used, the appearance with "Main" and "Aux" markings does not look appropriate with the arrangement on the Airacobra.

Fortunately, programming a new Left-Right Fuel Selector was not terribly difficult.
Creating new bitmaps for the gauge was the most difficult part.

On this Gauge, there are three status positions:
Left - Left Tank selected
Right - Right Tank selected
Center - Something other than Left or Right Tank is selected.

Note that ONLY the Left or Right Tank can be manually selected using this gauge.
The Center position is just an indicator that the current selection is something the gauge does not understand.

From this gauge it was pretty easy to create a Left-Right-Center Selector.
One might wonder why such a gauge would be useful considering that the options are the same as on the stock P51D or Hurricane_1 Fuel Selectors.
The difference is that there are two mouse areas and it is not necessary to cycle through all three positions though it may be necessary to pass through the center position to get from one side to the other as one might expect with an actual Fuel Selector.

- Ivan.

 

[Ivan]

Next Steps

So where do we go from here?

My goal in regards to Fuel Selectors is to create specific gauges that are useful for my own projects and to learn enough to be able to write the code needed for any other gauges that are useful.

These are the steps I intend to take in working with new gauges (but with an occasional diversion to keep things interesting):

1. Figure out the coding needed to access every Fuel Tank that may be specified in a CFS AIR file.
Tanks are the following
Record - Description
525 Left Tank
526 Right Tank
527 Left Aux Tank
528 Right Aux Tank
529 Left Tip Tank
530 Right Tip Tank
531 Center Tank 1
532 Center Tank 2
533 Center Tank 3

Note that all of these tanks may be accessed by some combination of the stock fuel selectors except for the Left and Right Tip Tanks (Records 529, 530) as Hubbabubba has already pointed out earlier. Unfortunately, these tanks are also the most reasonable representation of the fuel system in two of my projects.

2. Build a gauge set that allows for separate control of the fuel tanks used by Port and Starboard engines.
This is the typical arrangement of control for a twin engine aircraft.

3. Attempt to create a gauge that would be able to draw "simultaneously" from more than one fuel tank.
In theory this should be possible with a few coding tricks.

Further description of development will be in the Gauge Creation thread

- Ivan.