A couple of questions about fuel tank modelling

[CrazyDuck]

1. How are fuel tanks modelled in this sim from consumption point of view:

Does each plane have a simplified one big virtual tank (liters/gallons countdown if you will) or do planes have multiple of them separated (where historical), with player input need to switch between them, affecting the COG, preventing fires... etc.?

 

2. How's damage modelling done: If one tank gets an unsealed leak is it always going to drain entire plane empty with time, or are other fuel tanks unaffected?

 

3. Regarding self-sealing fuel tanks:

I can't recall ever seing a fuel leak seal after some time (not even from rifle caliber hits). Are they modelled? 

It's a relatively early period for self sealing fuel tanks, but they should be present on many modelled AC.

 

As example I'm attaching a page from magazine "Flight" from 1940, describing Ju 88 self sealing tanks.

 

4. Drop tanks: Any ideas why they are not modelled - is there any word they will be sometime?

I agree the sim is oriented around short-mission scenarios, so need for them is minimized, but for historical sake they would be interesting to have.

 

Cheers!

[ACG_pezman]

Well, you are not the first person to ask these questions, so much so that a new fuel tank model is slated for sometime in the future.

 

What we do know is:

 

1. You have multiple tanks on your aircraft, but they work as one big one.
2. If one tank gets damaged it will drain all your tanks
3. I don't think the self sealing stops leaking right now, however it will stop fires.  The Ju-88 is one aircraft that can be put out and saved if you get caught on fire.
4. No clue on drop tanks, it's been talked about, but the dev's are more concerned with getting the game working more "as advertised" when they sold the original IL2 BOS (think more single-player updates, campaign, graphics, memory loads, etc...).

We have been told by Jason that they are looking into added more functionality into the fuel tank systems, allowing for players to choose what tanks to feed from, allow or stop cross-feeding, etc... 

 

People are not happy that when a wing tank gets punctured it will drain all their fuel despite the fact that you could have switched to the damaged tank, used up what fuel was left in their before it all leaks out, then cut it off and switch the the undamaged tanks.

 

TL;DR:  Each aircraft has multiple fuel tanks (as designed) but they all cross-feed and you cannot stop it.  So when one tank gets punctured, it will eventually drain all your tanks.  And self-sealing fuel tanks, as far as I am aware, do not stop the fuel leak, just help put out fires at the moment.  However everything you asked for is planned at some point in the future.  And the IL2 Dev's have a great reputation for doing what they say they will.  It may take some time, but if they say they will do it, they will.  Or at least they will tell you they wont do it and why they wont.  They never leave us hanging.

[F/JG300_Gruber]

About point N°3 :

 

Self sealing fuel tanks are modelled in game. They work kind of instantly on small bullet sized holes, with no leaking effect showing at all. On fat holes (or bunch of small ones grouped together), self sealing tanks were uneffective IRL so when in game you see fuel leaking, it is when the hole is too big for the self sealing layer to take care of it. Hence it will not go away after some time.

 

I asked this question to the devs last year, and I believe it was Han that gave me this explanation.

[CrazyDuck]

Thanks for explanation lads.

[ACG_pezman]

About point N°3 :

 

Self sealing fuel tanks are modelled in game. They work kind of instantly on small bullet sized holes, with no leaking effect showing at all. On fat holes (or bunch of small ones grouped together), self sealing tanks were uneffective IRL so when in game you see fuel leaking, it is when the hole is too big for the self sealing layer to take care of it. Hence it will not go away after some time.

 

I asked this question to the devs last year, and I believe it was Han that gave me this explanation.

Wow, didn't know that. 

 

Or... they didn't do anything and just said that, lol. Just kidding, the dev's here are pretty good.

[Sgt_Joch]

In the announcement of Bodenplatte, it was mentioned that drop tanks would be added to the game.

 

 

-Improvements to aircraft fuel systems and add drop tanks

Edited January 31, 2018 by Sgt_Joch

[Luger1969]

Hi chaps. Need to ask something. The A20 that we are getting does it have self sealing tanks (irl) or not? Wiki says:  

A-20B The A-20B received the first really large order from the Army Air Corps: 999 aircraft. These resembled the DB-7A rather than the DB-7B, with light armor and stepped rather than slanted glazing in their noses. In practice, 665 of these were exported to the Soviet Union, so only about one third of them served with the USAAF.   A-20C The A-20C was an attempt to develop a standard, international version of the DB-7/A-20/Boston, produced from 1941. It reverted to the slanting nose glass, and it had RF-2600-23 engines, self-sealing fuel tanks, and additional protective armor.  

[Retrofly]

Is it me or do fuel tanks and fuel never catch fire? From most fottage I've seen of a2a hits on fighters, fires seem to occur regularly yet never really happen in game, unless the engine itself is on fire.

[Mauf]

Is it me or do fuel tanks and fuel never catch fire? From most fottage I've seen of a2a hits on fighters, fires seem to occur regularly yet never really happen in game, unless the engine itself is on fire.

 

I've seen fuel fires (both first person or third:) ) in game. You have to remember that many loadouts do not feature incendiary ammo (the orange ammo type, just in case) in the longer ranged small caliber guns, so those are out when it comes to starting a fire. That leaves the high caliber weapons, on often mixed belts no less so it's 50/50, and they only effectively land a few hits in your average bounce (after which, most planes are already damaged beyond recovery so there is no going for a burner either). So if you count the opportunities down where you could actually land an incendiary hit on a fuel tank, it's rather low after you passed through all the chances. Also remember that gun footage is no statistical representation of anything so trying to deduce a rate of occurrence from it is stretching it at best.

[Dakpilot]

I've seen fuel fires (both first person or third:) ) in game. You have to remember that many loadouts do not feature incendiary ammo (the orange ammo type, just in case) in the longer ranged small caliber guns, so those are out when it comes to starting a fire. That leaves the high caliber weapons, on often mixed belts no less so it's 50/50, and they only effectively land a few hits in your average bounce (after which, most planes are already damaged beyond recovery so there is no going for a burner either). So if you count the opportunities down where you could actually land an incendiary hit on a fuel tank, it's rather low after you passed through all the chances. Also remember that gun footage is no statistical representation of anything so trying to deduce a rate of occurrence from it is stretching it at best.

 

Most (all?) Russian aircraft have inert gas fire suppression systems fitted, so this cuts the chance down by a factor again, 

 

Bf 109 multi layer 'aluminium' rear fuel tank armour is supposed to have suppressing effect on incendiary rounds, but no one ever copied it , effect is not known to be totally reliable  (not sure if depicted in game)

 

Cheers, Dakpilot

Edited February 1, 2018 by Dakpilot

[Cpt_Cool]

I thought the "self-sealing" tanks use a dense hard rubbery material that leave a very small hole when pierced, like those "self healing" shooting targets if you have seen those. So its sort of an instantaneous thing if it is going to work.

[Mitthrawnuruodo]

It will be interesting to see exactly what is meant by ‘improvements to aircraft fuel systems’.

 

Will it give the player full control over tank selection, pumps, crossfeed, etc. or just drain tanks in a realistic way?

[[APAF]VR_Spartan85]

At the rate technology and in game improvements are made... I feel we are all going to have to re-learn this entire sim at some point

[Tapi]

Typical self-sealing tanks have multiple layers of rubber and reinforcing fabric, one of vulcanized rubber, and one of untreated natural rubber, which can absorb fuel, swell, and expand when it comes into contact with the fuel. When a fuel tank is punctured, the fuel seeps into the layers, causing the untreated layer to swell and thus seal the puncture.

 

Source: Wiki

[CrazyDuck]

 

 

incendiary ammo (the orange ammo type, just in case)

 

Doesn't orange denote HE ingame? 

 

Incendiary can be either AP (API) or HE (HEI).

[Mauf]

Doesn't orange denote HE ingame?

 

Incendiary can be either AP (API) or HE (HEI).

 

I think it (orange) means/acts like both? This is purely from own experience, so nothing founded in proper statistics, but I get my enemy burners with orange or mixed orange belts and never recall getting a burner on a pure blue belting.

 

So I assumed that blue means an AP - Ball/Tracer mixed belting and orange means a ball/Tracer - incendiary/HE mixed belting (incendiary/HE depending on what ammo types were available for the specific gun as for example the Mgeschoss for German 20mm).

 

I would be interested if someone has more accurate info on this actually? What does Blue and Orange actually represent in terms of belting and what bullet types can be expected with what loadout?

 

It could very well be that on certain guns, a blue belting would include incendiary types but then we would need to know on a per gun basis. Could become quite confusing.

 

In the end, it wouldn't change much about the effect for the discussion above. If every nth bullet in your belt is an incendiary type, you would get a chance to cause a fuel burner on every nth rotation of the belting only. Depending on "on-target" time, that becomes slim pretty quickly. 

Edited February 2, 2018 by Mauf