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Developer Diary | Plane Designer

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Hello, and welcome back to another Dev Diary for the upcoming By Blood Alone DLC and accompanying Patch 1.12! The team has returned from the summer vacation, and we are now back fixing bugs and tweaking the balancing of the new features and focus trees.

Today, we are taking a look at the Plane Designer. As always, any number value that you are going to see in this DD is subject to change.

The Plane Designer became a subject of discussion, both inside the team and in the community, almost as soon as we announced that No Step Back would feature a Tank Designer. We felt that it would mesh well with the rework of the Italian focus tree, not least because the Italian aviation industry was very well developed and produced some of the best combat airplanes of the war - hampered mostly, as Italy so often was, by lacking production capacity.

We also felt that a Plane Designer would help plug some gaps in the lineup of available aircraft. Over the years, many players have commented on the fact that many nations modified their fighters to also be able to carry bombs, or their tactical bombers to also carry torpedoes. One of the big goals of the Plane Designer was to allow for these types of multi-role aircraft.

At the same time, we didn’t want to make these multi-role planes too powerful. Instead, a plane design optimized for a single mission should still be more effective than a multi-role plane. Where multi-role planes offer flexibility, optimized designs offer top performance, if you can afford them.

The basics of the Plane Designer are probably not a surprise for anyone who is familiar with the Ship or Tank Designers. The base is called an airframe, which roughly corresponds to the hulls and the chassis of the ship and tank designers. The Airframes have a number of module slots, where you can put the modules that give the final design its actual stats. There are three different size classes of airframes: Small, Medium, and Large. Small planes also come in a carrier-capable variant of the airframe.

The types of module slots in the Plane Designer are slightly different from the Tank Designer. There are effectively only three types of slots: Engines, Weapons, and Special modules.

Engine modules are perhaps the most straightforward of them. Unlike tanks, where this slot dictates what type of engine the tank uses and a separate stat determines what its speed is, engine modules in the plane designer determine the number and power of the engines mounted on the aircraft. These engine modules produce a new stat called Thrust, while all other modules have another new stat called Weight. These two stats are effectively the limiting factor of what and how many modules you can put on the plane. A design is only legal if Weight does not exceed Thrust (some people might point out that the only planes with a Thrust/Weight ratio of 1 or better in reality are modern, high-performance fighter jets, but these people will be summarily ignored).

Any excess Thrust is converted into extra speed, which is intended to provide a reason not to fill every module slot.

One thing to note here is that jet engines (and rocket engines, for that matter) are part of these engine slots, which means that they are available for all types of planes. This, by necessity, means that Jet Fighters and other jet-powered airplanes are no longer their own unit type - they are now simply fighters with jet engines. Jet fighters will therefore reinforce regular fighter wings, and also that you can now effectively make jet carrier planes, jet CAS, jet heavy fighters etc.with the plane designer.
Or Rocket Naval Bombers, one supposes, if you really hate your pilots on a personal level.
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Weapon modules are also fairly self-explanatory. But beyond providing offensive stats like Air Attack, weapon modules fulfill two other major functions. The first is that the weapons define what type of plane a design ends up being. For this the designer has a Primary Weapon Slot. The module in this slot defines the role of the final design, i.e. Fighter, CAS, Naval Bomber etc.

This is relevant because the weapon modules also unlock what missions a design has available. That means that the strict separation of mission by type of aircraft will be gone. You can now create fighters that can provide ground support, or Strategic Bombers that can do naval strikes, depending on the modules you put on the plane. There are, of course, some restrictions - strat bombers can never mount the modules necessary to unlock air superiority missions, for example.

We still wanted to give you an easy way to classify your designs on a high level and it also makes it a lot easier to tell the AI what a design actually is and how it should be used. Without accounting for doctrines, there are no stat differences between, say, a fighter that has a set of 4 Heavy MGs in the Primary Weapon Slot and bombs in a secondary weapon slot, and a CAS that has the bombs in the primary weapon slot and the MGs in the secondary slot - but one goes into Fighter Airwings and the other goes into CAS Airwings.
CAS planes have a large variety of weapons available to them to attack ground targets.
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There is a full list of weapons, the missions they unlock, and what they classify a plane as if mounted in the primary weapon slot, below (stats omitted because balancing is still ongoing):

ModuleMissions UnlockedType
2x Light MGAir Superiority, InterceptFighter, Heavy Fighter
4x Light MGAir Superiority, InterceptFighter, Heavy Fighter
2x Heavy MGAir Superiority, InterceptFighter, Heavy Fighter
4x Heavy MGAir Superiority, InterceptFighter, Heavy Fighter
Cannon IAir Superiority, InterceptFighter, Heavy Fighter
2x Cannon IAir Superiority, InterceptFighter, Heavy Fighter
Cannon IIAir Superiority, InterceptFighter, Heavy Fighter
2x Cannon IIAir Superiority, InterceptFighter, Heavy Fighter
Rocket RailsClose Air Support, Logistics StrikeCAS
Bomb LocksClose Air Support, Naval Strike, Port StrikeCAS
Small Bomb BayClose Air Support, Logistics Strike, Port StrikeCAS
Tank Buster IClose Air Support, Logistics StrikeCAS
Tank Buster IIClose Air Support, Logistics StrikeCAS
Torpedo MountingNaval Strike, Port StrikeNaval Bomber/Maritime Patrol Plane
Guided Anti-Ship MissileNaval Strike, Port StrikeNaval Bomber/Maritime Patrol Plane
Fixed Explosive ChargeKamikaze StrikesSuicide Craft
Medium Bomb BayClose Air Support, Logistics Strike, Strategic BombingTactical Bomber
Large Bomb BayStrategic Bombing, Port StrikeStrategic Bomber

While some of these weapons are unlocked in the (reworked) Air Tech Tree, some of them are also found outside of it, in a similar manner as the tank weapons are found in various trees. I will note that the total number of techs in the Air tech tree has actually decreased.
A view of the Air Tech tree. It has a total of 28 techs, compared to the old tree’s 38 techs.
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One notable aspect is that a lot of these modules provide different stats only for specific missions. For true multi-role planes to make sense, we wanted to make sure that building a design with a mixed set of missions didn’t make the plane useless in some of them. Hanging bombs off a plane should make it less agile and slower, but a fighter that was able to do CAS missions shouldn’t be useless in air superiority missions. Thus, the weight and agility penalties only apply to the fighter if it is actually on a CAS mission, not if it is on an air superiority mission.

Modifiers only apply to certain missions. Here, the bombs the Stuka carries make it less agile, but the dive brakes give it better air defense
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Finally, we have the so-called “Special” module slots. These are effectively a catch-all term of various different items, a list of which you can find below:​

Armor Plate: Increased Air Defense, reduced range
Self-Sealing Fuel Tanks: increased Air Defense, costs Rubber
Drop Tanks: increased range (small airframes only)
Extra Fuel Tanks: increased range, reduced air defense
Dive Brakes: increased air defense, increased naval strike hit chance
Radio Navigation I: reduced night penalty, increased strat attack
Radio Navigation II: reduced night penalty, increased strat attack
Air/Ground Radar: reduced night penalty, increased strat attack, increased naval detection
Air/Ground Radar II: reduced night penalty, increased strat attack, increased naval detection
Air/Air Radar: reduced night penalty when on intercept mission
Air/Air Radar II: reduced night penalty when on intercept mission
Floatplane: increased naval spotting (small airframes only)
Flying Boat: increased naval spotting (medium+large airframes)
LMG Defensive Turret: increased Air attack, reduced agility
2x LMG Defensive Turret: increased Air attack, reduced agility
HMG Defense Turret: increased Air attack, reduced agility
2x HMG Defense Turret: increased Air attack, reduced agility
Cannon Defense Turret: increased Air attack, reduced agility
2x Cannon Defense Turret: increased Air attack, reduced agility
Recon Camera: unlocks recon mission (LaR only)
Demining Coil: unlocks demining mission (MtG only)
Bomb sights I: increased strat attack
Bomb Sights II: increased strat attack
Non-Strategic Materials: reduced Aluminum cost, reduced air defense

Special Modules are primarily intended to help optimize planes for various missions or give them different niches.

The eagle-eyed amongst you have already spotted that planes now have a surface and sub detection stat. Up until now, planes that were active in a sea zone always provided a flat bonus to the spotting speed of any navies active in the seazone. This will now change, with planes having dedicated spotting stats that determine how well they do with helping the navies spot. There are modules, like the Air-Ground Radar and the Flying Boat hull, which give bonuses to naval spotting.

Vanilla planes have those stats already baked in, with some being better than others - carrier planes are better than their land-based counterparts, naval bombers are better than fighters etc.

To further support this, we are adding two more things: Maritime Patrol Planes as a dedicated unit type and a special Naval Patrol mission for planes with the right modules.

Maritime Patrol Planes are built on the Large Airframe, giving them exceptional range. They are able to mount the whole array of naval bomber weapons, but naval strike is really not intended to be their primary role. Maritime Patrol Planes are meant to help with spotting raiders in the deep ocean, where smaller planes with shorter ranges struggle to provide much mission efficiency.
You can run naval patrol missions with many different types of planes.
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Finally, let’s talk a bit about art! While we already have a large amount of historical art for various plane types, we also wanted to give you more options to visually distinguish your designs, even if it is just to find the plane design more easily in the production menu. For the tank designer, we split up the existing art and recombined it into various combinations to quickly generate a large number of assets. We realized early on that this wouldn’t work for the plane designer. So instead, we decided to fill in some gaps in the existing art as well as add some art for a number of prototypes that flew but were historically passed over for mass-production.
Here is a partial list of new plane icons coming in BBA. Which one’s your favorite?
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We also decided that we wanted to add more 3d art. Much like the tank designer, you can select these assets when you design the plane. We are adding about 80 new 3d models for planes to the DLC, but more on that in the future!
Here is just a teaser of some of the new assets coming in the DLC:
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That is about it for this week. We hope that you will enjoy playing with the Plane Designer as much as we enjoyed making it. To end this DevDiary on a personal note: The Plane Designer will be my final contribution to Hearts of Iron 4. After close to 6 years on the project, all the way from the early days on Together for Victory, the time has come for me to leave the company and move on to greener pastures. It has certainly been an eventful and productive couple of years, and there are many things that I am very proud of (and a few that I regret - like adding Austria-Hungary as a joke and then finding out that people love monarchism). Working on the Hearts of Iron series has always been a dream for me, since the day I launched Hearts of Iron 1, almost 20 years ago now. Few people can say that they had an impact on a piece of entertainment that has had a similar impact on themselves. But the thing I am most proud of is the team we have built. Hearts of Iron is in very good hands, and there are years of content still to be released. I’m looking forward to it - but, once again, as a player.​

Weird designs that QA came up with:
This single plane outguns an entire tank platoon, unfortunately it can’t ever turn:
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And then we restricted the number of bomb bays you can have on a plane:
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6 engines, 8 cannons, 4 cannons in turrets, and a production cost 50% higher than a strategic bomber. Needless to say, this combo is no longer possible:
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When you look at the Spitfire Mark I’s armament and wonder: but what if…more guns?
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For both Bristol Blenheim VI and He-115, I can only find articles description for such modifications but not any old pictures or blueprint. However, as every plane you mentioned has at least one designated rear gunner, how can you tell those guns would be controlled by the pilot instead of the rear gunners, hence those rear pointing guns should not be count as turret, as in your previous post?
My original point was that those guns are not controlled by the pilot. The point is that fixed guns that are not controlled by the pilot do not have any aiming mechanism, and so are very poor in their air attack performance. As far as I can tell they were mounted in an attempt to 'scare off' fighters approaching from behind, but I don't think they were very successful even at that.

Thrust in the next DLC surely is not the thrust IRL. I would be amused if the thrust of a pistol engine in game would decrease with the flying speed of the plane as IRL. So as the drag it surely won’t be speed dependent. As making thrust and drag speed dependent would be more complicated than putting altitude zones mechanism into the game.
"Thrust" I take to mean power, since that is not speed dependent, and "Drag" would be drag coefficient - also not speed dependent. The maximum speed is then the cube root of "Thrust" divided by "Drag".

Therefore, the “drag barrier” of any modules should be break very easily with advance engine, or else every non-jet float plane would have negative thrust. Therefore, a module max speed is need to ensure some modules can only work in certain speed range. Like you cannot put a fix floats/gear on a Rocket Plane and fly 1000 km/h .
'Thrust' and 'Drag' can't be a linear (Thrust - Drag) relation because that would not make any sense at all.

In coding perspective it would be a hard stop for exploit you are not going to able to balance without recoding a large portion of the code.
The code would need to change to allow for cube root of a variable, anyway, for this to work properly.

It is needed to be simple and referable. If the states was set too abstract, Dev or Modder would need more time and effort to mod and balance the game for each new change. If the new variable can “workablely” anchored to specifications, like wing area, to plane IRL. It would save a lot of time for everyone in the future.
I don't see anything complex or "unworkable" in the cube root of Thrust/Drag. A spreadsheet will calculate it on the fly trivially.

Climb rate is not agility, How fast you climb doesn’t mean how tight you turn. Hawker Tempest V has good climb rate but bad agility, while Fokker Dr.I has good agility but bad climb rate. Those two things cannot really mix together and call it a day
It would be lovely to have separate elements of Agility, but absent a more detailed treatment of altitude that's not feasible. So an abstracted "Agility" includes climb speed. Climb speed is in any case dependent on power ("Thrust") to weight ratio, and together with wing loading this is generally the determinant of manoeuvrability.

Agility is more than turn rate even without the inclusion of climb speed. Rotation rate, acceleration, altitude slip and other things also factor in - and they rely on things like wing length, shape factors and power-to-weight ratio.

The 'wing lift coefficient' is notionally multiplied by takeoff speed to get maximum takeoff weight, but since takeoff speed is not something you could reasonably set (because runway length is not a factor in HoI), this could probably just be simplified to have each wing module give a maximum weight total for all components. "Agility" would then be Thrust divided by Weight times (Maximum Wing Weight minus total actual Weight). An aircraft at maximum weight would therefore have Agility = 0.

Edit to add: I just realised that power-to-weight should probably figure in the wing weight capacity, too, because acceleration is relevant to takeoff. Hmm. So the Max. Weight actually needs to be the square root of 'Thrust' times the wing lift factor.
 
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Question like that, what you will design as planes when the patch come out ?

(Me, as I'm extremely boring and believe in streamlining, that is I prefer to have thousands of non-specialized fighters instead of several hundreds max-min ones) :

A) Either a machine gun armed or light cannon armed superiority fighter with as much range as possible
B) A two engine bomber to use primary on logistical strikes on land and for naval/port strikes if needed
 
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My original point was that those guns are not controlled by the pilot. The point is that fixed guns that are not controlled by the pilot do not have any aiming mechanism, and so are very poor in their air attack performance. As far as I can tell they were mounted in an attempt to 'scare off' fighters approaching from behind, but I don't think they were very successful even at that.
Sorry for the misunderstanding in your previous post.

"Thrust" I take to mean power, since that is not speed dependent, and "Drag" would be drag coefficient - also not speed dependent. The maximum speed is then the cube root of "Thrust" divided by "Drag".
Thrust is force, power is power. The piston engine has constant power, and speed-dependent thrust and the jet engine has constant thrust and speed-dependent thrust. If the game has both things, it is very likely that Thrust here represents neither.

'Thrust' and 'Drag' can't be a linear (Thrust - Drag) relation because that would not make any sense at all.
The code would need to change to allow for cube root of a variable, anyway, for this to work properly.
Even the thrust now mentioned in the dev diary didn't work in a cube root way. Why do you think that they would change to allow for the cube root of a variable? I believe Net Thrust = Engine Thrust - Drag would possibly be the best the current dev team can do.

I don't see anything complex or "unworkable" in the cube root of Thrust/Drag. A spreadsheet will calculate it on the fly trivially.
What are you referring to, I am saying "quotients for lift and drag for wings" as an input variable is "unworkable" for modder and game dev, not for the game itself. To disprove my point, may you provide the "root of Thrust/Drag" or "quotients for lift and drag for wings" of Me-262 A-1 in a float input, which is usually used as the variable input format of the game file.

It would be lovely to have separate elements of Agility, but absent a more detailed treatment of altitude that's not feasible. So an abstracted "Agility" includes climb speed. Climb speed is in any case dependent on power ("Thrust") to weight ratio, and together with wing loading this is generally the determinant of manoeuvrability.
Agility is more than turn rate even without the inclusion of climb speed. Rotation rate, acceleration, altitude slip and other things also factor in - and they rely on things like wing length, shape factors and power-to-weight ratio.
Please kindly do not distort the meaning of Agility, Agility of a plane means how good a plane can turn horizontally. Fw-190 has a good Rotation rate, Me-163 has good acceleration, and neither of those planes was described as agile. Fokker Dr.I has a bad Rotation rate and acceleration, but has a tight turning radius and was described as an agile plane. Rotation rate, acceleration, and turning radius are three totally different factors depending on 3 different variables. Rotation rate, acceleration, and turning radius, and their respective dependent variable (Wings Shape, Engine Power, and Wings Area) should have their adequate presentation within the game.

The 'wing lift coefficient' is notionally multiplied by takeoff speed to get maximum takeoff weight, but since takeoff speed is not something you couls reasonably set (because runway length is not a factor in HoI), this could probably just be simplified to have each wing module give a maximum weight total for all components. "Agility" would then be Thrust divided by Weight times (Maximum Wing Weight minus total actual Weight). An aircraft at maximum weight would therefore have Agility = 0.
In this case, would Fw-190 have better agility than A6M Zero, as it has a better Power/mass ratio despite it having a much worse turning radius?
 
Sorry for the misunderstanding in your previous post.
No problem.

Thrust is force, power is power. The piston engine has constant power, and speed-dependent thrust and the jet engine has constant thrust and speed-dependent thrust. If the game has both things, it is very likely that Thrust here represents neither.
As with agility, below, you can call it what you like but the game quantity "Thrust" currently works as if it was power, so I assume it represents power.

Even the thrust now mentioned in the dev diary didn't work in a cube root way. Why do you think that they would change to allow for the cube root of a variable? I believe Net Thrust = Engine Thrust - Drag would possibly be the best the current dev team can do.
That will not just produce unrealistic answers, it will produce answers that are problematic in a game sense, I think. Exploitable without further (artificial) limitation. I'm not saying I expect them to do it differently - I'm saying that it seems to me that the system will cause issues until it gets done this way, if it ever does. I suppose I'm looking at the Devs a little bit similarly to the way Churchill supposedly described the Americans: "you can always rely on them to do the right thing - once they have exhausted all of the other possibilities..."

What are you referring to, I am saying "quotients for lift and drag for wings" as an input variable is "unworkable" for modder and game dev, not for the game itself. To disprove my point, may you provide the "root of Thrust/Drag" or "quotients for lift and drag for wings" of Me-262 A-1 in a float input, which is usually used as the variable input format of the game file.
I am a modder. I have modded in reasonable representations of all aircraft types that were used in action in WW2 using the current "upgrades" system by making assessments of the game characteristics of all of the planes. With the new builder, though, this will not be the problem; the game characteristics will be an amalgam of the effects of all the different airplane components combined in the builder.

Drag for all components separately promises to be a real bear to figure out, but wing lift at takeoff is actually not that hard; it's wing area times wing loading, so for each aircraft an initial estimate would be effective wing area times maximum wing loading for that type of aircraft (taking power-to-weight into account in 'type').

Please kindly do not distort the meaning of Agility, Agility of a plane means how good a plane can turn horizontally. Fw-190 has a good Rotation rate, Me-163 has good acceleration, and neither of those planes was described as agile. Fokker Dr.I has a bad Rotation rate and acceleration, but has a tight turning radius and was described as an agile plane. Rotation rate, acceleration, and turning radius are three totally different factors depending on 3 different variables. Rotation rate, acceleration, and turning radius, and their respective dependent variable (Wings Shape, Engine Power, and Wings Area) should have their adequate presentation within the game.
Depends on the books you read - I usually find that all these things are taken into account in assessing "Agility" or "Manoeuvrability". But note that it is a combination of these elements that matters; excelling at one of them while futzing out on the others is not going to give a good Agility. The Fw-190, for example, does not have overall good agility (mainly because it has such a high wing loading - around 1.5 times that of a Spitfire), despite having good rotation.

As an aside, these things are linked; the FW has good rotation through having short wings (for its overall size and power), but short wings struggle to have much wing area without creating loads of drag... This is an example of the way design always fights with itself - it's true in real life, and it means that an uber-strong "meta" is generally impossible to get. A game that genuinely represents this would constitute a 'Holy Grail', as far as I'm concerned.

In this case, would Fw-190 have better agility than A6M Zero, as it has a better Power/mass ratio despite it having a much worse turning radius?
The indicative agility factor I use for the Waltzing Matilda mod is Power-to-Weight ratio divided by Wing Loading; the Fw-190 A-1 has an Agility Factor of 1.91 (note - as calculated from actual aircraft stats; this is not the Agility in game, which is obviously higher, being multiplied by a factor) while the A6M2-11 Rei Sentoki has a factor of 2.84. So, no.
 
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A pet idea that I have is that national focus/spirits and doctrinal choices could allow or even force the player to make some design choices, eventually corrected by air experience...or not.

Example, the more or less useful bewildering array of defensive guns on American heavy bombers, guns that had (understatement) a very relative effect on ennemy fighters. People taking the strategic bombing route could have them by default, then either remove them for better payload, get bonus for escort fighters, or stick to the guns and improve them.

(I'm a big fan of air exp being used of, shall we say, a retroactive way. Because thats a big issue I have with HOI IV in general, but the playerc can design equipment that will work well from the get go, and not, say, equipment that the 1930s governments thought would work (ergo, countless deathtraps fielded by Italy, France, the UK...)
 
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(I'm a big fan of air exp being used of, shall we say, a retroactive way. Because thats a big issue I have with HOI IV in general, but the playerc can design equipment that will work well from the get go, and not, say, equipment that the 1930s governments thought would work (ergo, countless deathtraps fielded by Italy, France, the UK...)
To be fair, most equipment from the get-go worked pretty well for what it was designed to do... the problem, generally, was that the fighting didn't happen as it was expected to happen, so stuff was needed that did things none of the available kit had been designed to do. The solution to this might be to gate some types of equipment behind doctrines, say. That would need a major system development effort, but it might work well.
 
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No problem.


As with agility, below, you can call it what you like but the game quantity "Thrust" currently works as if it was power, so I assume it represents power.

So yes, as you agreed, "Thrust" here is not representing neither thrust nor Power IRL. It is just a game indicator that indicates how strong the in-game engine is, and it might not be speed-dependent and the thrust drag relationships can be linear instead of cube root, even if drag would be implanted into the game. The module max speed variable is just an applicable artificial limitation I proposed if the thrust drag relationship is linear instead of cube root. So I believe this is the end of the discussion for the definition of "Thrust" in-game.
That will not just produce unrealistic answers, it will produce answers that are problematic in a game sense, I think. Exploitable without further (artificial) limitation. I'm not saying I expect them to do it differently - I'm saying that it seems to me that the system will cause issues until it gets done this way, if it ever does. I suppose I'm looking at the Devs a little bit similarly to the way Churchill supposedly described the Americans: "you can always rely on them to do the right thing - once they have exhausted all of the other possibilities..."


I am a modder. I have modded in reasonable representations of all aircraft types that were used in action in WW2 using the current "upgrades" system by making assessments of the game characteristics of all of the planes. With the new builder, though, this will not be the problem; the game characteristics will be an amalgam of the effects of all the different airplane components combined in the builder.
Drag for all components separately promises to be a real bear to figure out, but wing lift at takeoff is actually not that hard; it's wing area times wing loading, so for each aircraft an initial estimate would be effective wing area times maximum wing loading for that type of aircraft (taking power-to-weight into account in 'type').
Wing load = Plane Mass/ Wing area, wing area times wing loading just equal to Plane Mass. So I believe it didn't work like that.

Depends on the books you read - I usually find that all these things are taken into account in assessing "Agility" or "Manoeuvrability". But note that it is a combination of these elements that matters; excelling at one of them while futzing out on the others is not going to give a good Agility. The Fw-190, for example, does not have overall good agility (mainly because it has such a high wing loading - around 1.5 times that of a Spitfire), despite having good rotation.
As an aside, these things are linked; the FW has good rotation through having short wings (for its overall size and power), but short wings struggle to have much wing area without creating loads of drag... This is an example of the way design always fights with itself - it's true in real life, and it means that an uber-strong "meta" is generally impossible to get. A game that genuinely represents this would constitute a 'Holy Grail', as far as I'm concerned.
I don't really get it, maybe there is some misunderstanding. It seems that you agree that Plane Weight, Engine Power(Thrust), and Wing Area, are the major factors determining the agility of a plane, but you want loads of drag or loads of lift instead of wing area as the new editable variable. The things you are saying are more like what variable you want to add into the next DLC instead of how it works as a game mechanism.
The indicative agility factor I use for the Waltzing Matilda mod is Power-to-Weight ratio divided by Wing Loading; the Fw-190 A-1 has an Agility Factor of 1.91 (note - as calculated from actual aircraft stats; this is not the Agility in game, which is obviously higher, being multiplied by a factor) while the A6M2-11 Rei Sentoki has a factor of 2.84. So, no.
Power-to-Weight ratio divided by Wing Loading = (Power/Plane Mass) /( Plane Mass/ Wing area) = (Power*Wing area/ Plane Mass^2)
All following data is from wiki, as it is the easiest way to access data for dev and modder
Fw 190 A-8
Power-to-Weight = 0.29–0.33 kW/kg (0.18–0.20 hp/lb) (I use the big one here)
Wing loading: 241 kg/m2 (49 lb/sq ft)

Power-to-Weight ratio divided by Wing Loading = 0.33/241 = 0.00137 kW*m^2/kg^2 or 0.2/49 = 0.00408 hp sq ft/lb^2

A6M2

Power/mass: 0.294 kW/kg (0.179 hp/lb)
Wing loading: 107.4 kg/m2 (22.0 lb/sq ft)
Power-to-Weight ratio divided by Wing Loading = 0.294/107.4 = 0.00274 kW*m^2/kg^2 or 0.179/0.22 = 0.00814 hp sq ft/lb^2
To eliminate the difference caused by using different units, we would compare the ratio between two planes. The ratio of the Power-to-Weight ratio divided by Wing Loading of Fw190 and A6M2 is 2 here, which is larger than that from the data you provided (2.84/ 1.91 = 1.487)

May you kindly show how you calculate your numbers?
 
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So yes, as you agreed, "Thrust" here is not representing neither thrust nor Power IRL. It is just a game indicator that indicates how strong the in-game engine is, and it might not be speed-dependent and the thrust drag relationships can be linear instead of cube root, even if drag would be implanted into the game. The module max speed variable is just an applicable artificial limitation I proposed if the thrust drag relationship is linear instead of cube root. So I believe this is the end of the discussion for the definition of "Thrust" in-game.
If the "Thrust" and drag relation is linear then we have departed real world physics and we might as well play fantasy games. "Thrust" does not change with velocity, thus I treat it as equivalent to power, since power is the (almost) constant factor for the great majority of engines in the era.

Wing load = Plane Mass/ Wing area, wing area times wing loading just equal to Plane Mass. So I believe it didn't work like that. besides how would that be an easier
No, wing lift is wing loading at maximum takeoff weight. Ie it is the wing loading where the plane can just barely get off the ground, not the normal wing loading for the specific aircraft. This can be approximated by the effective wing area times the square root of the power-to-weight ratio times a factor for runway length, etc. Alternatively, as a rough estimate you could look at maximum takeoff weights for a similar speed aircraft, and use that wing loading times the effective wing area of the aircraft you are working on. Some aircraft - especially bombers - tended to take off heavily loaded to the point where you couldn't get off the ground with much more load. These examples make useful guides as to maximum wing loadings (which can then be used to estimate the maximum takeoff weight of other aircraft; it's not very accurate, but it's good enough for game purposes).

I don't really get it, maybe there is some misunderstanding. It seems that you agree that Plane Weight, Engine Power(Thrust), and Wing Area, are the major factors determining the agility of a plane, but you want loads of drag or loads of lift instead of wing area as the new editable variable. The things you are saying are more like what variable you want to add into the next DLC instead of how it works as a game mechanism.
Wing area is not a very useful game variable in itself. It might be used in the calculation of game variables, but it doesn't work well as a thing defined in the game files - that's all I'm saying.

As for how the new system works, I don't know in detail; I'm just trying to express what it should be according to real world physics. The physics is important not from the point of view of exact "realism", but in broad, power relations terms (ie is it a square root, linear or cubic relation?) because this defines how the tradeoffs will work in real design. If the DLC mechanism does not allow for or accord with these relations (which I don't think it will, but I don't know, in detail), then it will be problematic in-game to some degree.

Power-to-Weight ratio divided by Wing Loading = (Power/Plane Mass) /( Plane Mass/ Wing area) = (Power*Wing area/ Plane Mass^2)
All following data is from wiki, as it is the easiest way to access data for dev and modder
Fw 190 A-8
Power-to-Weight = 0.29–0.33 kW/kg (0.18–0.20 hp/lb) (I use the big one here)
Wing loading: 241 kg/m2 (49 lb/sq ft)

Power-to-Weight ratio divided by Wing Loading = 0.33/241 = 0.00137 kW*m^2/kg^2 or 0.2/49 = 0.00408 hp sq ft/lb^2

A6M2

Power/mass: 0.294 kW/kg (0.179 hp/lb)
Wing loading: 107.4 kg/m2 (22.0 lb/sq ft)
Power-to-Weight ratio divided by Wing Loading = 0.294/107.4 = 0.00274 kW*m^2/kg^2 or 0.179/0.22 = 0.00814 hp sq ft/lb^2
To eliminate the difference caused by using different units, we would compare the ratio between two planes. The ratio of the Power-to-Weight ratio divided by Wing Loading of Fw190 and A6M2 is 2 here, which is larger than that from the data you provided (2.84/ 1.91 = 1.487)

May you kindly show how you calculate your numbers?
Sure:

Power for FW-190 A-1 = 1540 hp; weight = 9100 lb (takeoff weight); wing area = 197 sq.ft.
P/W = 1540/9100 = 0.17
Wing loading = 9100/197 = 46.2

Power for A6M2-11 = 940 hp; weight = 5313 lb; wing area = 242 sq.ft.
P/W = 940/5313 = 0.18
Wing loading = 5313/242 = 22.0

I think the reason for the discrepancy is that I forgot to say I use the square root of the ratio (sorry), so:

FW-190 A-1: sq.root (1000 * 0.17 / 46.2) = 1.92
M6A2-11: sq.root (1000 * 0.18 / 22) = 2.86

The numbers in the spreadsheet are 1.91 and 2.84, so I guess there are rounding errors in my calculations here (where I only used 2 decimal places). The point of the original statement still stands, though - the FW is less Agile despite having higher power, because Agility depends on several things and the other things (notably weight and wing area) also matter. Your own figures show the same thing (albeit with different detail), so I don't really understand your point.
 
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If the "Thrust" and drag relation is linear then we have departed real world physics and we might as well play fantasy games. "Thrust" does not change with velocity, thus I treat it as equivalent to power, since power is the (almost) constant factor for the great majority of engines in the era.
Good luck with not departing with real-world physics; many variables in-game, like the Firepower of artillery, progress linearly instead of according to the volume of the shell, which would be the square of the caliber of the cannon.
No, wing lift is wing loading at maximum takeoff weight. Ie it is the wing loading where the plane can just barely get off the ground, not the normal wing loading for the specific aircraft. This can be approximated by the effective wing area times the square root of the power-to-weight ratio times a factor for runway length, etc. Alternatively, as a rough estimate you could look at maximum takeoff weights for a similar speed aircraft, and use that wing loading times the effective wing area of the aircraft you are working on. Some aircraft - especially bombers - tended to take off heavily loaded to the point where you couldn't get off the ground with much more load. These examples make useful guides as to maximum wing loadings (which can then be used to estimate the maximum takeoff weight of other aircraft; it's not very accurate, but it's good enough for game purposes).

I still don't get what the use of maximum takeoff weight in your vision is. With plane designer, players can design their plane, why a rough estimate of maximum takeoff weights for a similar speed aircraft would be required?
Wing area is not a very useful game variable in itself. It might be used in the calculation of game variables, but it doesn't work well as a thing defined in the game files - that's all I'm saying.

As for how the new system works, I don't know in detail; I'm just trying to express what it should be according to real world physics. The physics is important not from the point of view of exact "realism", but in broad, power relations terms (ie is it a square root, linear or cubic relation?) because this defines how the tradeoffs will work in real design. If the DLC mechanism does not allow for or accord with these relations (which I don't think it will, but I don't know, in detail), then it will be problematic in-game to some degree.
The problem is you suggest many variables, but you didn't tell us how they can work together and calculate a meaningful value or their role in the combat formula.

Sure:

Power for FW-190 A-1 = 1540 hp; weight = 9100 lb (takeoff weight); wing area = 197 sq.ft.
P/W = 1540/9100 = 0.17
Wing loading = 9100/197 = 46.2

Power for A6M2-11 = 940 hp; weight = 5313 lb; wing area = 242 sq.ft.
P/W = 940/5313 = 0.18
Wing loading = 5313/242 = 22.0

I think the reason for the discrepancy is that I forgot to say I use the square root of the ratio (sorry), so:

FW-190 A-1: sq.root (1000 * 0.17 / 46.2) = 1.92
M6A2-11: sq.root (1000 * 0.18 / 22) = 2.86

The numbers in the spreadsheet are 1.91 and 2.84, so I guess there are rounding errors in my calculations here (where I only used 2 decimal places). The point of the original statement still stands, though - the FW is less Agile despite having higher power, because Agility depends on several things and the other things (notably weight and wing area) also matter. Your own figures show the same thing (albeit with different detail), so I don't really understand your point.
Isn't it better to let the game do the calculation? Why would you think your agility vectors that need to be calculated by spreadsheet would be more approachable inputting than the raw data(the weight, wing area, and engine power (thrust))? Besides, how do you know the final weight of the plane to calculate the agility, when the player needs to design and add modules into the plane with plane designer in-game?
 
Good luck with not departing with real-world physics; many variables in-game, like the Firepower of artillery, progress linearly instead of according to the volume of the shell, which would be the square of the caliber of the cannon.
How do you come up with that conclusion, when the calibre of artillery ordnance is not specified anywhere in the game? It certainly doesn't increase with technology, since Great War artillery could be huge!

I still don't get what the use of maximum takeoff weight in your vision is. With plane designer, players can design their plane, why a rough estimate of maximum takeoff weights for a similar speed aircraft would be required?
Weight does two things: it degrades Agility (by increasing wing loading and reducing power-to-weight ratio) and it has a hard limit in that you can only get so much mass off the ground with a given engine and wing. Hence, you need a measure of "Weight" for any designed aircraft, and you need a measure for how much weight a given engine and wing can lift.

Wings and engines also have weight and produce drag. Maximum speed is determined by engine power and total drag. That's it - as simple as that.

The problem is you suggest many variables, but you didn't tell us how they can work together and calculate a meaningful value or their role in the combat formula.

Isn't it better to let the game do the calculation? Why would you think your agility vectors that need to be calculated by spreadsheet would be more approachable inputting than the raw data(the weight, wing area, and engine power (thrust))? Besides, how do you know the final weight of the plane to calculate the agility, when the player needs to design and add modules into the plane with plane designer in-game?
The combat, I am assuming, would work just as it does now. The output values would be the same as are there now. The question is what the input values need to be for each component.
 
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To be fair, most equipment from the get-go worked pretty well for what it was designed to do... the problem, generally, was that the fighting didn't happen as it was expected to happen, so stuff was needed that did things none of the available kit had been designed to do. The solution to this might be to gate some types of equipment behind doctrines, say. That would need a major system development effort, but it might work well.

An example of thing that could be ''corrected with experience'' have been mentionned a lot in the previous pages, floatplanes. The value of carriers was not always well understood by admirals, but, by Jove, the value of floatplanes was ! It seems that most interwar ship designs were an exercice in fitting as many catapulted seaplanes as humanly possible on a ship. They proved extremely useful for SAR and gunnery spotting for land bombardment...but for proper naval combat, they were more often than not fire hazard and many extensive aviation facilities ended up being removed
 
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How do you come up with that conclusion, when the calibre of artillery ordnance is not specified anywhere in the game? It certainly doesn't increase with technology, since Great War artillery could be huge!
Yes AFAIK (at least for Germany), every type of guns’(AA,AT,Artillery Naval) calibre in-game increase with technology.
Weight does two things: it degrades Agility (by increasing wing loading and reducing power-to-weight ratio) and it has a hard limit in that you can only get so much mass off the ground with a given engine and wing. Hence, you need a measure of "Weight" for any designed aircraft, and you need a measure for how much weight a given engine and wing can lift.
How do you calculate wing load without the variable of wing area?
Wings and engines also have weight and produce drag. Maximum speed is determined by engine power and total drag. That's it - as simple as that.

The combat, I am assuming, would work just as it does now. The output values would be the same as are there now. The question is what the input values need to be for each component.

But thrust and drag is in cube root relationship into the equation. How do you do that without changing the equation ?
 
Yes AFAIK (at least for Germany), every type of guns’(AA,AT,Artillery Naval) calibre in-game increase with technology.
?? Germany had a 42cm "Gamma" howitzer in the Great War (developed in 1906). What WW2 artillery was bigger? If that was "high technology" then why were 15cm field guns being used (15cm sFH 36, produced from 1938 to 1942 and listed as the second artillery model for Germany in HoI IV, although I assume that "Artillery 2" really represents a range of guns because otherwise there are loads missing)?
Other examples abound; the 8,8cm Flak-16 anti-aircraft gun was produced in 1917 and 1918 - what WW2 AA guns have larger calibre?

How do you calculate wing load without the variable of wing area?
It's the total load that the wings can lift. The wing area affects it, but they are not the same thing because more advanced wings get more lift per unit area.

But thrust and drag is in cube root relationship into the equation. How do you do that without changing the equation ?
The combat equations use maximum speed and agility. The combat algorithm does not need a cube root equation; the derivation of mazimum speed from engine power and drag does, but that is not (luckily) a combat equation.
 
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?? Germany had a 42cm "Gamma" howitzer in the Great War (developed in 1906). What WW2 artillery was bigger? If that was "high technology" then why were 15cm field guns being used (15cm sFH 36, produced from 1938 to 1942 and listed as the second artillery model for Germany in HoI IV, although I assume that "Artillery 2" really represents a range of guns because otherwise there are loads missing)?
Other examples abound; the 8,8cm Flak-16 anti-aircraft gun was produced in 1917 and 1918 - what WW2 AA guns have larger calibre?
Oh sorry they fixed German tech tree already, you may look at the Romania tech tree, Romania Artillery 2 started production in 1934 and Artillery 2 started production in 1917.

German Artillery 3 and German Artillery 2 shell IRL have the same weight, yet, even with using the range, the max range of German Artillery 3 IRL is 24,500 m the firepower in-game is 34, and German Artillery 2 IRL is 13,325 m, and the firepower in-game is 30. How can the range difference of 11,175 m translate to the increase of 4 firepowers in-game?
If even this cannot convince you the progression of value through the tech tree has always been set linearly, I don't know how I can convince you that.
AFAIK 42cm "Gamma" howitzer is an Army level artillery not a battalion level artillery. You may find a German Army WWII TOE for more information.
And 12.8 cm FlaK 40 has a larger caliber than 8,8cm Flak-16.

It's the total load that the wings can lift. The wing area affects it, but they are not the same thing because more advanced wings get more lift per unit area.
The maximum weight the wings can lift doesn't equal the plane weight per wing area.
Besides, isn't the lift per unit area of wings more dependent on the flying velocity of the plane than the wing design itself?
And without the wing area, how can you get the total lift, this only works if every type of plane has a unified fixed value of wing area.
The combat equations use maximum speed and agility. The combat algorithm does not need a cube root equation; the derivation of mazimum speed from engine power and drag does, but that is not (luckily) a combat equation.
The weight and drag of the plane load out will be mission dependent, I think the maximum speed and agility cannot be calculated before you assign air missions to the squadron.
 
If even this cannot convince you the progression of value through the tech tree has always been set linearly, I don't know how I can convince you that.
Because of the way that attacks compare to defenses, each point of attack is worth more than the previous because it's more likely to be above enemy defense and deal additional damage.
 
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Oh sorry they fixed German tech tree already, you may look at the Romania tech tree, Romania Artillery 2 started production in 1934 and Artillery 2 started production in 1917.

German Artillery 3 and German Artillery 2 shell IRL have the same weight, yet, even with using the range, the max range of German Artillery 3 IRL is 24,500 m the firepower in-game is 34, and German Artillery 2 IRL is 13,325 m, and the firepower in-game is 30. How can the range difference of 11,175 m translate to the increase of 4 firepowers in-game?
Accuracy and rate of fire also matter, plus explosive used, yadda, yadda... Basically, artillery techs are an abstraction of many things. The fact that they are linear means nothing, basically - it's an aesthetic game choice.

If even this cannot convince you the progression of value through the tech tree has always been set linearly, I don't know how I can convince you that.
AFAIK 42cm "Gamma" howitzer is an Army level artillery not a battalion level artillery. You may find a German Army WWII TOE for more information.
And 12.8 cm FlaK 40 has a larger caliber than 8,8cm Flak-16.
My point was (I think - I'm starting to lose the will to live...) that in real life technology does not mean gun calibre. This doesn't really apply in the game, either, no matter what the flavour text says.

The maximum weight the wings can lift doesn't equal the plane weight per wing area.
No, obviously not, but the maximum that the wing can lift a takeoff speed is the maximum weight at which the plane can become airborne. The only time this is not relevant is for something like the post-war US jet - the Pirate, I think it was - for which the testing report said "we cannot recommend the use of this design of plane for any duty that involves flying". I found that a brilliant bit of understated criticism.

Besides, isn't the lift per unit area of wings more dependent on the flying velocity of the plane than the wing design itself?
Yes, it is. Read what I wrote in several posts above. Total wing lift at takeoff velocity is what is relevant.

And without the wing area, how can you get the total lift, this only works if every type of plane has a unified fixed value of wing area.
Yes, I have wing areas for all plane models, but in the designer this is not how it has to work. To get different wing lift for different aircraft, it will be necessary to have different wing models, each of which might be seen as having a different wing area. Rather than a wing area, though, it would be better to assign a wing lift parameter that is total lift at takeoff speed. Unless wing area can be a numerical rating like armour is for tanks, maybe - hmm... if that works it might be a good way to do it.

The weight and drag of the plane load out will be mission dependent, I think the maximum speed and agility cannot be calculated before you assign air missions to the squadron.
You need a maximum speed and agility for the plane. Mission modifiers might be possible, but having mission specific values for every mission for every plane would be just horribly messy.
 
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What is the status of weight here, for example, can it restrict a ship from launching from an aircraft carrier?
For example, the maximum weight that can be launched from a merchant ship converted carrier is different from that of a large carrier at the end of the war. (Larger and heavier!)
So what I am saying is, can we add a status like "maximum weight" to a ship, such as an aircraft carrier, to limit the aircraft that can take off?
It would be nice if a "weight" could be implemented like this.
I think it would be more realistic if the weight could be used to determine whether a ship can be loaded or not.
 
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Yes AFAIK (at least for Germany), every type of guns’(AA,AT,Artillery Naval) calibre in-game increase with technology.
Only the 'Fluff' name. I am still annoyed that the 'fluff' name for Germany's starting artillery is a 10.5cm Light Howitzer, but every other country has a roughly ~75mm caliber name.

It has long been assumed that artillery (including AA and AT) were an amalgam of the guns used during that period of military history. So even though the fluff name goes 10.5cm, 15cm, etc. it really just means that that designation was the most prevalent produced during that period.
 
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Accuracy and rate of fire also matter, plus explosive used, yadda, yadda... Basically, artillery techs are an abstraction of many things. The fact that they are linear means nothing, basically - it's an aesthetic game choice.


My point was (I think - I'm starting to lose the will to live...) that in real life technology does not mean gun calibre. This doesn't really apply in the game, either, no matter what the flavour text says.
So do the thrust and drag, if it is going to be implement, they would very likely to progress linearly, thus a compromising limit (like module max speed) should add to the game, instead of changing the whole system
No, obviously not, but the maximum that the wing can lift a takeoff speed is the maximum weight at which the plane can become airborne. The only time this is not relevant is for something like the post-war US jet - the Pirate, I think it was - for which the testing report said "we cannot recommend the use of this design of plane for any duty that involves flying". I found that a brilliant bit of understated criticism.


Yes, it is. Read what I wrote in several posts above. Total wing lift at takeoff velocity is what is relevant.

Yes, I have wing areas for all plane models, but in the designer this is not how it has to work. To get different wing lift for different aircraft, it will be necessary to have different wing models, each of which might be seen as having a different wing area. Rather than a wing area, though, it would be better to assign a wing lift parameter that is total lift at takeoff speed. Unless wing area can be a numerical rating like armour is for tanks, maybe - hmm... if that works it might be a good way to do it.

Maybe make up a less complicated mechanism for the dev to reference would be better, the current mechanism you proposing seems more complicated than the altitude air zone mechanism I proposed previously.

You need a maximum speed and agility for the plane. Mission modifiers might be possible, but having mission specific values for every mission for every plane would be just horribly messy.
This is how the dev diary said how would it be done, Mission load out would affect the agility and max speed, the cube root drag system would very unlikely to be comparable with the current dev direction, so I believe the thrust here would very likely to be linearly progress.
 
A good thing to introduce in missions would be the ever critical altitude, especially for level bombers (two engine and four engine). Simply said, at the altitudes where you might possibly drop a bomb in the general viccinity of the target, you are immensely vulnerable to AA fire (that would be one of those things ''learn from experience'' I alluded to : British and Americans were persuaded they could use level bombers to destroy targets from far above, and learned very painfully that it did not work, especially against tactical targets)

And to conclude (well....one week for release) this thread on a interesting feature (I want to see you all next week on ''the plane designer is bugged''), I would suggest once more that one vital piece of equipement, by far the most vital component of airwarfare, is not neglected. The component that is far more fragile and difficult to produce that engines, airframes, guns or bombs and that paid a terrible price when someone decided that astral navigation was the way to go or that escort fighters were useless.

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