Drop Tanks.

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el cid again
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RE: Drop Tanks.

Post by el cid again »

Now, if the game value ranges are already taking into effect the addition of drop tanks, I would like to see some authoritative data on that

That is easy. The Zero is exhaustively documented. No one claims it could fly any of the scenario ranges without its centerline drop tank.
Yet none of the scenarios use that drop tank. There are endless arguments about if it should have a range of this or that - based on pilot endurance - but not about can it fly that far. And NO ONE is arguing "it cannot go that far without the extra 1/3 of its fuel" - as they probably should be! But the game testers and modders posted in several threads that drop tanks had no function - and with such language it sounded like they had it confirmed by programmers.
el cid again
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RE: Drop Tanks.

Post by el cid again »

If the endurance value = max range and is already taking into account the use of drop tanks then what could be done is to zero the effect value therefore no endurance/range changes but the load value would still restrict bomb loading at extended radius's.

1) Determine the value added for each tank
2) Subtract the value added for all tanks from the transfer range of the plane

Query - the value added is transfer range - right?

That is tricky - no change in the plane screen - only in the unit screen.
Awfully obscure for me.
el cid again
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RE: Drop Tanks.

Post by el cid again »

From what i've seen adding drop tanks will change the ranges and if as el cid has stated ranges are already including the use of drop tanks then adding them will give an additional increase in range. Either the endurance value for a/c should be changed to a value representing max range on internal fuel or the 'effect' value for drop tanks should be zeroed.

Since no scenario uses drop tanks, the ranges had to include them if they mattered. Odd that the P-47 didn't get its range (if it didn't) but the Zero did! But this data is dirty - that is typical - not exceptional - and it is just as bad pro Allied as pro Japanese (or anti anti). It is true - I have to either zero the tank effect or mess with the range - and confirm all this by testing. Ugh.
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JeffroK
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RE: Drop Tanks.

Post by JeffroK »

I had a tinker with my mod of Niks Mod.

I took the drop tank off my A6M2 Reisan and got different extended ranges

With Tanks
Maximum 35 hexes/2100 miles
Extended 11 / 700
Normal 8 / 525

Without tanks
Maximum 33 hexes / 1980 miles
Extended 11 / 660 miles
Normal 8 / 495

I will fit bigger tanks to other aircraft and see what happens.

Now this Pandoras Can of Worms seems to have an answer, what would it do to manouverability ???

P47D

With 1 x 200gal Tank
Maximum 33 hexes/1980 miles
Extended 11 / 6600
Normal 8 / 495

Without tanks
Maximum 19 hexes / 1140miles
Extended 6 / 380 miles
Normal 4 / 285
Interdum feror cupidine partium magnarum Europae vincendarum
el cid again
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RE: Drop Tanks.

Post by el cid again »

I had a tinker with my mod of Niks Mod.

I took the drop tank off my A6M2 Reisan and got different extended ranges

With Tanks
Maximum 35 hexes/2100 miles
Extended 11 / 700
Normal 8 / 525

Without tanks
Maximum 33 hexes / 1980 miles
Extended 11 / 660 miles
Normal 8 / 495

I will fit bigger tanks to other aircraft and see what happens.

Now this Pandoras Can of Worms seems to have an answer, what would it do to manouverability ???

The ranges for Zero - with or without drop tanks - seem too high. After all the grief I took about Zero range, I find it amazing. But never mind that - the impact of the drop tank itself is TOO SMALL. And the concept of "fitting a larger drop tank" is one from science fiction: the special drop tank was integral to the Zero design, was unique in several respects,
and was not subject to great modification. Theoretically two small bombs might be replaced by drop tanks - these weigh 66 kg and would hardly matter - but since the bomb points are not "wet" - and since making them so would be excessively difficult given the intentionally weakened structure - it is not a real option. If you DID add 2x66 kg drop tanks, the durability of the aircraft should be decreased (they are now unarmored targets with nice fuel air mixtures in the "wet" wings)!

Further, it appears that the attitude here is "add the drop tank, accept the range" - instead of "add the drop tank, figure out how much the range increases, and decrease it by that amount." Further, the original data seems not to be correct. To the extent you are interested in historical simulation, you need to take the data of the plane as designed and usually flown. If you are a JFB and want the unusual range - and are willing to ignore our code cannot limit the number of planes (as in real life) to the more experienced pilots - you then must at least use the much lower cruising speed required for the longer range (which will impact your ability to intercept and how long it takes to get places).
el cid again
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RE: Drop Tanks.

Post by el cid again »

Now this Pandoras Can of Worms seems to have an answer, what would it do to manouverability ???

The basic problem is deciding "what matters operationally" and "how can we plug that into what matters in the specific air combat code of WTIP"?

This is not an easy thing to do.

First, "what matters operationally" is not always the same thing. In fact,
you need to begin with the elementary knowledge that durability, firepower, speed, maneuverability and altitude ALL COMBINED matter LESS THAN one quite different factor ALONE matters: surprise. Both offensively and defensively, surprise is an order of magnitude more important than the sum or product of ALL other factors. So this is a marginal matter - it probably matters more in the game world than in reality - but this game is very sophisticated - and it DOES have lots of die rolls, some of which can be interpreted as meaning surprise was achieved.

Second, more often than not, speed matters more than maneuverability does. Thus, a plane with an altitude (actually energy) advantage can buy some speed, and use that to make an attack (or escape) run it could not normally make, demonstrating that success can really be a function of speed. In WITP code, according to material disclosed in this forum, while there are many factors in the air combat routine, the dominant one is called "maneuverability". Statistical analysis of the "maneuverability rating" of stock aircraft shows this is, for the simple, single engine case, either maximum speed divided by 10, or that same factor combined with a small amount (10%) of rate of climb data. [At first I was upset with this. But careful analysis caused me to learn that it works, and not just for WWII era aircraft, to a remarkable degree. Eventually I increased the fraction to 20%, but retained the original practice.]

Now one can take a wholly different approach - and all my life I have done - following some more complex simulations. Maneuverability is usually defined in terms of power loading, wing loading and turning rates.
Many also add in rate of climb. The very best maneuverability ratings actually change at different altitudes: my own system gives you a "rate of climb correction factor" (and similar adjustments), and recalculates maneuverability at each altitude (in increments of 10 meters or about 33 feet). [Rate of climb is, by definition, either 100 feet per minute, or 30 meters per minute - they are virtually the same value - at the service ceiling - and zero under stable forward flight conditions at the absolute ceiling. The ROC correction factor is the amount ROC decreases every level until you reach service ceiling, at which point the ROCCF is doubled, until you reach an altitude at which ROC = 0.] In a similar way, speed is modified by a speed correction factor - except that speed INCREASES until the aircraft reaches its optimum operating altitude, then it DECREASES between that altitude and service celing. Figuring out what the speed or rate of climb is for any given altitude is quite different than what we need here: we are allowed only ONE value in ONE field. And figuring out how to combine loading, ROC, speed, turn rates, etc - is very very tricky - since there is no one thing that always dominates - and since the amount of any given thing really varies with lots of factors.

The first step in simplification is to believe in the code. It considers altitude - so leave that alone. It gives higher planes an advantage or disadvantage for altitude. It almost certainly considers surprise - so leave it alone.

The second step in simplification is to understand what we can do in this model: give each plane one average value. Theory aside, we can't do more than that. That forces us to decide "what matters most, most of the time" and, maybe, "what else matters, and in what proportion to what matters most?" Here the genius of the design shines: speed matters most. Using speed as the dominant factor was the right design decision.

The third step in simplification is to understand what data we have, and can get. IF you must use something in your calculation that is not already in the data set - THEN you must be able to get that factor in equal validity for all planes - even those that never flew and cannot be measured. Rate of turn might be very nice to use - but (a) it is almost never recorded in standard references; (b) it is not measured for many aircraft in the data set. Gathering the data for rate of turn will turn generating this one factor into a task that would take a man year - more or less - to achieve - and might not be very valid - since so many estimates would be required.

OK - that is the process simplified - make your choices.
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m10bob
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RE: Drop Tanks.

Post by m10bob »

ORIGINAL: el cid again
I had a tinker with my mod of Niks Mod.

I took the drop tank off my A6M2 Reisan and got different extended ranges

With Tanks
Maximum 35 hexes/2100 miles
Extended 11 / 700
Normal 8 / 525

Without tanks
Maximum 33 hexes / 1980 miles
Extended 11 / 660 miles
Normal 8 / 495

I will fit bigger tanks to other aircraft and see what happens.

Now this Pandoras Can of Worms seems to have an answer, what would it do to manouverability ???

The ranges for Zero - with or without drop tanks - seem too high. After all the grief I took about Zero range, I find it amazing. But never mind that - the impact of the drop tank itself is TOO SMALL. And the concept of "fitting a larger drop tank" is one from science fiction: the special drop tank was integral to the Zero design, was unique in several respects,
and was not subject to great modification. Theoretically two small bombs might be replaced by drop tanks - these weigh 66 kg and would hardly matter - but since the bomb points are not "wet" - and since making them so would be excessively difficult given the intentionally weakened structure - it is not a real option. If you DID add 2x66 kg drop tanks, the durability of the aircraft should be decreased (they are now unarmored targets with nice fuel air mixtures in the "wet" wings)!

Further, it appears that the attitude here is "add the drop tank, accept the range" - instead of "add the drop tank, figure out how much the range increases, and decrease it by that amount." Further, the original data seems not to be correct. To the extent you are interested in historical simulation, you need to take the data of the plane as designed and usually flown. If you are a JFB and want the unusual range - and are willing to ignore our code cannot limit the number of planes (as in real life) to the more experienced pilots - you then must at least use the much lower cruising speed required for the longer range (which will impact your ability to intercept and how long it takes to get places).

Sid, if we use historical observation alone as an example, I can prove you are correct in assuming the "game" Zero was "given" the tanks..
Saburo Sakai's "Samurai" went into great detail to account ONE particular mission in which they had to fly with Betty bombers from Rabaul to the 'Canal, and he recounts they "just made it"..
Well, remember the big stink that was made by gamers that the Zero at one point was missing that same range by ONE HEX?
(Don't remember which version/mod that was, but it was corrected so the Zeke could make that distance.)
Further, your observations (IMHO) MUST be correct that ranges (especially for the P47, F4F, and F6F (amongst others) are using the "clean" non-tank ranges for missions *other than ferry range*, (and those ranges are wrong as well according to the detailed sites I found yesterday.)
For instance, I have always felt something was dreadfully wrong about the F6F being a vast improvement over the F4F, with nearly 2 full years of combat experience in the F4F, yet in the game, they share the same LOUSY range of *4*, when in reality the F6F had at least a 50% improvement over the F4F..(See the site I linked yesterday).
The fact EVERY P47 coming thru Australia was given a minimum of that 200 gal tank was NEVER an option, and rather than say the original designer "got it wrong", I must believe he just went "by the books" of internal fuel and used that figure, and that ( as mentioned in a prior comment) "if a plane was a fighter-"bomber", we MUST do something to prevent players from using the plane WITH both a tank AND a bomb..(Sadly this thought was ignorant of the fact that sometimes those planes were outfitted with both!)
Gen Kenney, on the other hand, (as historical accounts have shown, did NOT want the P47 for FB's, but as a single-engined escort for his bombers, FROM DAY ONE!!!!!)
IMHO, it is not necessary to re-vamp all planes, just a few of the "basic" (or obvious) examples.
The P47 and F6F come to mind, as does the Hayabusa.....
At present, every game P47 is using the range of internal fuel only, (and it is wrong as soon as the internal tank went from 307 gallons to 375 gallons on the 2nd production model!)Please see my prior threads for model details.....
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el cid again
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RE: Drop Tanks.

Post by el cid again »

Well, I did revamp all aircraft, and it took a long time - and a lot of hard work - since I found no definitions for the factors needed I had to figure out what the game really was designed to use? In the end I changed armament, durability, maneuverability, the way ceiling is calculated,
and looked up reference book ferry range. Presumably that ALWAYS includes drop tanks - although I was operating on what may be incorrect information - that the code does NOT extend range for drop tanks. If it really does - then the reason they are ignored is that figuring out correct range then become a very hard job - and time consuming (time = money in business).

While I found many errors, and corrected them, I am unable to see how an F6F is "at least 50% better" than an F4F-4 (or an F4F-3 - which may be better in fact - according to contemporary experts: it was better to have 4 guns with ammo for longer than 6 guns - it was more maneuverable - it had more range - etc). No single factor does (or could) rate a plane well - but the factors I ended up with do not show that kind of superiority. The fact we still felt F4Fs combat worthy and put them on many carriers late in the war must indicate they were competative:

Type Maneuver Speed ROC Durability Firepower Range
F4F-3 21 333 2030 5 8 832
F4F-4 20 318 1950 5 12 770
F6F-5 25 380 2980 7 12 1003

Clearly the F6F is surperior in all respects but firepower. But 50% better? Only in ROC can that be said.
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m10bob
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RE: Drop Tanks.

Post by m10bob »

ORIGINAL: el cid again

Well, I did revamp all aircraft, and it took a long time - and a lot of hard work - since I found no definitions for the factors needed I had to figure out what the game really was designed to use? In the end I changed armament, durability, maneuverability, the way ceiling is calculated,
and looked up reference book ferry range. Presumably that ALWAYS includes drop tanks - although I was operating on what may be incorrect information - that the code does NOT extend range for drop tanks. If it really does - then the reason they are ignored is that figuring out correct range then become a very hard job - and time consuming (time = money in business).

While I found many errors, and corrected them, I am unable to see how an F6F is "at least 50% better" than an F4F-4 (or an F4F-3 - which may be better in fact - according to contemporary experts: it was better to have 4 guns with ammo for longer than 6 guns - it was more maneuverable - it had more range - etc). No single factor does (or could) rate a plane well - but the factors I ended up with do not show that kind of superiority. The fact we still felt F4Fs combat worthy and put them on many carriers late in the war must indicate they were competative:

Type Maneuver Speed ROC Durability Firepower Range
F4F-3 21 333 2030 5 8 832
F4F-4 20 318 1950 5 12 770
F6F-5 25 380 2980 7 12 1003

Clearly the F6F is surperior in all respects but firepower. But 50% better? Only in ROC can that be said.

Your figures for the F6F range are still a 25% improvement..I still feel that is an improvement over a range of "4"..
Why would the Navy have a Helldiver(range 6) and keep a fighter with no better range than what they started the war with?
Well, of course, they didn't..They made the F6F bigger to allow for the carrying of tanks(etc) to allow for the longer-legs needed over vast oceans.
****************************************************************

Just throwing this in as an after thought....Wingloading...I doubt if many people realize that the F6F was darned near as big as the P47!!
Compared to the F4F, the F6F was huge! I keep hearing how the design of the F6F was based on that captured Alaskan Zero, but if this is true, size had nothing to do with it whatsoever..
Grumman pretty much took some of the finer points of the F4F, blew it up, and (with certain improvements) came out with the F6F..This is really a "shoot from the hip" appraisal, but the point I am making is that the USN learned from prior "miscalculations" in plane design, (the range of the Japanese planes vs the Coral Sea era range of the USN planes) for one, and knew the range of the F6F had to be an improvement on the F4F..
They also knew it was cheaper to design a plane "big enough to handle a droptank" than to design a plane with internal tanks to compensate for that load, because if internally, the entire plane must be designed to accept added protection, power compensation for the added weight and shift of plane balance/gravity,etc.
An external tank can be dumped prior to combat and go in "clean".
The tank was of course cheaper than the "permanent" cost of the provision for the fuel to be carried/compensated internally.
I am positive the game F6F(stock) made no provision whatsoever for the droptank range of the F6F, (amongst others).

"The Hellcat was fitted with three self-sealing fuel tanks, one with a capacity of 227 liters (60 US gallons) under the pilot's seat, and one in each wing with a capacity of 331 liters (87.5 US gallons), for a total of 889 liters (235 US gallons) -- over twice the fuel capacity of the Wildcat. The F6F-3 could also carry a 568 liter (150 US gallon) centerline drop tank, though most F6F-3 production had no provisions for carrying any other external stores."

BTW, the Hellcat was in wartime production in 2 major versions, the F6F-3 and the F6F5. The only really major difference being that the F3 was purely a fighter,(no provision for wingbombs whatsoever), and F5 could handle a 1000 lb bomb under EACH wing, (along with that center droptank).
Told ya' it was a big plane.[:D]



http://www.vectorsite.net/avf6f.html
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el cid again
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Some game data

Post by el cid again »

One must be careful about putting too much faith in what is written in the manual - or on the board!

Examining UNIT description of plane performance I find

Normal range is 25% of transfer range
Extended range is 33% of transfer range

Further, I find a range for a zero with its real drop tank is 2220 miles - converted by the code to 37 hexes - fully 12 at extended range - 2 more than intended by me!

This is ugly - because planes do not all appear on any given date - and I need to know all plane ranges with drop tanks - to convert the range backwards to the right value

And I added a 200 gal drop tank to P-47D

and three drop tanks (1x200 plus 2x150) for P-47N -

which I found documented in American Warplanes of World War II.

This means all three P-47 models will have radically different ranges.

The P-47 will START as a moderate range fighter-bomber (although I classify it as a fighter for technical reasons in code) with a 500 pound bomb

and CHANGE to an escort fighter - armed entirely with guns and rockets - and drop tanks - UNLESS the code rolls convert it "upward" to different bombs (which sometimes happens) - on long range missions - but remain a fighter bomber on normal range missions.

I know - there are no rockets in the game - but there are in RHS.

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RE: Some game data

Post by m10bob »

This is ugly - because planes do not all appear on any given date - and I need to know all plane ranges with drop tanks - to convert the range backwards to the right value

If need be,we can look at the internal fuel capacity and find the clean range, and from this try to determine consumption of gallons per mile?
We'd have to "fudge" a tad as we don't know the aerodynamics of each type of drop tank, (to determine exact drag properties), but a "constant" could certainly be given, on a "guesstimate" of so many miles per tank, (as in the case of multiple tanks on some planes.)
Yeah, I know, you don't like "guesstimates", but its' an option...
I will be glad to find the internal fuel capacity on planes if you want me to?
Looks like there is enough interest to garner help if needed, as long as we all keep track of source materials, (for credibilities ' sake....)
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el cid again
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RE: Some game data

Post by el cid again »

If need be,we can look at the internal fuel capacity and find the clean range, and from this try to determine consumption of gallons per mile?

You are being logical - so you are wrong! That is what we SHOULD do - but you are forgetting our game "reality" is dictated by what code really does. Turns out we cannot do that - because the code has its own rule - probably an (unknown to us) algorithm. [Guess: something like 2 gallons = 1 minute endurance - which is different distances because of different cruising speeds]

So what we do is add the tank, look at what the data says in a unit (which in turn means we must put the thing in a unit and put the date so we can see it there) -
and compare it to the "clean" value -
and then enter our data in that context - so the ferry range is right with tanks. The code MODIFIES whatever we entered - and since we don't know by how much - we must "calibrate" - meaning measure it - and then adjust so the end result is right.
el cid again
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RE: Some game data

Post by el cid again »

We'd have to "fudge" a tad as we don't know the aerodynamics of each type of drop tank, (to determine exact drag properties), but a "constant" could certainly be given, on a "guesstimate" of so many miles per tank,

Really wrong. The same tank on a Zero will yield a radically greater range than on a P-whatever. Because the Zero os so light and fuel efficient. We need to do it for each plane - separate - not for each tank. Wish it were otherwise....
el cid again
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RE: Some game data

Post by el cid again »

I will be glad to find the internal fuel capacity on planes if you want me to?

Turns out this is hard to do - sometimes impossible - and wholly useless to us.

What matters to the game is RANGE - what we need is good range data - and mostly I think I have it (after a lot of hard work). We need to get that range data working with the code via the database.

For non- drop tank planes I have it. Now I need to figure it out for drop tank planes.

What I need from you is a list of planes that should have drop tanks but do not. Give me your address and I will give you a plane list. I have more planes and different ones than you are used to playing with.
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RE: Some game data

Post by RevRick »

Don't forget.. the P-38 flew with everything from 2 110 gal up to 2 310 gal tanks, and even flew with two [dummy] torpedos (though it was never used as a torpedo bomber!) and could carry two 2000# bombs, or a combination thereof. How's that to skew your projected calculations. (Let's see, one 2000# and a 310 gal drop tank..oy!)
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el cid again
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RE: Some game data

Post by el cid again »

Don't forget.. the P-38 flew with everything from 2 110 gal up to 2 310 gal tanks, and even flew with two [dummy] torpedos (though it was never used as a torpedo bomber!) and could carry two 2000# bombs, or a combination thereof. How's that to skew your projected calculations. (Let's see, one 2000# and a 310 gal drop tank..oy!)

Not a problem (finally - something).

WITP needs to know the maximum case - and it works out other combinations for us. What is ferry range (AKA transfer range) - no load but fuel - all fuel - including drop tanks.
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RE: Some game data

Post by m10bob »

ORIGINAL: RevRick

Don't forget.. the P-38 flew with everything from 2 110 gal up to 2 310 gal tanks, and even flew with two [dummy] torpedos (though it was never used as a torpedo bomber!) and could carry two 2000# bombs, or a combination thereof. How's that to skew your projected calculations. (Let's see, one 2000# and a 310 gal drop tank..oy!)

Can ya' believe the F6F was so big they even put a torpedo on a variant of it!!(It did not go into the field.)
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RE: Some game data

Post by RevRick »

I like the little tid bit I saw about the F4F you pointed out from that site. It was plumbed, and retrofit kits produced, to add a 58 (probably treat that as a 50) gal tank to each wing. An extra 100 gal. on the old Wildcat. Then the statement that the F6F could carry externally more fuel than the Wildcat could carry at all (IIRC).
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RE: Some game data

Post by m10bob »

ORIGINAL: RevRick

I like the little tid bit I saw about the F4F you pointed out from that site. It was plumbed, and retrofit kits produced, to add a 58 (probably treat that as a 50) gal tank to each wing. An extra 100 gal. on the old Wildcat. Then the statement that the F6F could carry externally more fuel than the Wildcat could carry at all (IIRC).

Yeah...Kinda makes me think small research was done regarding the "range" of some of the planes, or maybe they did not understand drop tanks were NOT for ferry range, but for combat missions?
Any kid growing up in the 50's and '60's made model airplanes, and had an idea which planes had drop tanks..F4F had 2 teardrops, from the F4F4 model on..(Game range of "4"??-NUTS!)
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el cid again
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RE: Some game data

Post by el cid again »

Can ya' believe the F6F was so big they even put a torpedo on a variant of it!!(It did not go into the field.)

The F7F actually DOES have a torpedo!
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