Do you want liquid fuel to be changed to realistic counterparts?

[SpaceFace545]

Liquid fuel could literally be anything and if they are adding metallic hydrogen deuterium and other fancy stuff they should probably split up liquid fuel into kerosene-for some rockets and jets, liquid hydrogen-for advanced rockets and fuel cells, Methane-for cool rocket engines, and hydrazine- for when You just want some plain cancerous fun. What are your thoughts?

[jimmymcgoochie]

Generic terms like liquid/solid fuel, oxidiser, electric charge etc. remove a lot of the complexity so new players don't get overwhelmed and also mean the same set of resources can be used everywhere without worrying about what exactly those resources are- they just work. I would be very surprised if that changed in KSP2.

There are plenty of mods for KSP that add different fuel types, from simple stockalike versions of liquid hydrogen and liquid methane to real rocket fuels, so expect similar mods to appear in KSP2 pretty quickly after its release so players who want MOAR REALISM can have the real fuels, players who want some stockalike cryo fuels or additional ion/magnetic engine options can have those and players who are just about able to understand fuel + oxidiser = boom can stick with that and not have to worry about hypergolics and kilowatt-hours etc. etc.

[SpaceFace545]

5 minutes ago, jimmymcgoochie said:

Generic terms like liquid/solid fuel, oxidiser, electric charge etc. remove a lot of the complexity so new players don't get overwhelmed and also mean the same set of resources can be used everywhere without worrying about what exactly those resources are- they just work. I would be very surprised if that changed in KSP2.

There are plenty of mods for KSP that add different fuel types, from simple stockalike versions of liquid hydrogen and liquid methane to real rocket fuels, so expect similar mods to appear in KSP2 pretty quickly after its release so players who want MOAR REALISM can have the real fuels, players who want some stockalike cryo fuels or additional ion/magnetic engine options can have those and players who are just about able to understand fuel + oxidiser = boom can stick with that and not have to worry about hypergolics and kilowatt-hours etc. etc.

I hear what you say but the advanced systems like metallic hydrogen will be doped with deuterium and other things to make it stable and we will have fusion engines that need to run on hydrogen. I would be very disappointed if engines that must run on hydrogen will just be substituted for liquid fuel. And I liquid hydrogen is in the game then engines such as the vector and nervas run on hydrogen in the real world.

[Bingleberry]

6 minutes ago, jimmymcgoochie said:

Generic terms like liquid/solid fuel, oxidiser, electric charge etc. remove a lot of the complexity so new players don't get overwhelmed and also mean the same set of resources can be used everywhere without worrying about what exactly those resources are- they just work. I would be very surprised if that changed in KSP2.

There are plenty of mods for KSP that add different fuel types, from simple stockalike versions of liquid hydrogen and liquid methane to real rocket fuels, so expect similar mods to appear in KSP2 pretty quickly after its release so players who want MOAR REALISM can have the real fuels, players who want some stockalike cryo fuels or additional ion/magnetic engine options can have those and players who are just about able to understand fuel + oxidiser = boom can stick with that and not have to worry about hypergolics and kilowatt-hours etc. etc.

As a console player, who will likely not get any mods, I’d love to see an “advanced fuel mode,” or something of that nature... if the mode is off, the fuel is generic (liquid, solid, liquid + oxidizer), if the mode is on, we can choose fuel types... I’d imagine that methalox and keralox would have certain utility, in particular situations compared to hydrogen or hydrazine (and oxygen) fuel mixes, and since there will be advanced fuels, it would add more depth and experimentation with different engine types (granted, I’m sure some fuels would be incompatible with some engines) ... or if fuel choices could be toggled in the “advanced tweakables”

[pandaman]

One of the strengths of KSP is it's accessibility by embracing simplification where possible, and reducing the number of different fuel types to just 4 components in KSP1 (LF, O, Solid, and Xenon) is a great example.

I wouldn't really have an issue with dividing say LF into 2 'levels' (Kerosene and Hydrogen for example) and perhaps the Oxidiser to match, keep one Solid fuel variant and then expand the 'specialised exotics', from currently just Xenon, to include Metallic Hydyogen etc.

To have too many 'standard' fuel types would just add unnecesary complexity IMO.

[jimmymcgoochie]

17 minutes ago, SpaceFace545 said:

I hear what you say but the advanced systems like metallic hydrogen will be doped with deuterium and other things to make it stable and we will have fusion engines that need to run on hydrogen. I would be very disappointed if engines that must run on hydrogen will just be substituted for liquid fuel. And I liquid hydrogen is in the game then engines such as the vector and nervas run on hydrogen in the real world.

Expect metallic hydrogen to be JUST metallic hydrogen, not 'metallic hydrogen with a little bit of deuterium in it'. Likewise fusion engines will probably use just 'helium-3' rather than 'helium-3 and deuterium/tritium'.

The current NERV in KSP uses liquid fuel anyway, and there are mods that can change it to run on liquid hydrogen e.g. Kerbal Atomics (which tries to make ALL nuclear engines run on liquid hydrogen instead of liquid fuel, even those from other mods).

@Bingleberry's suggestion of having fuel switches as an advanced tweakable option sounds like a good way of doing it, but this would also require fuel tanks etc. to also be switchable. Alternatively it could be an option in the game settings to allow fuel type switching. The option to switch fuel type could be unlockable in the tech tree, with the default being liquid fuel when the part is unlocked and the ability to use another fuel unlocked later. Liquid hydrogen as a rocket fuel isn't particularly energy dense so you need a lot more of it for the same delta-V compared to other fuels despite the greater ISP it offers.

I still expect the same resources and fuels to be present in KSP2 but would be pleasantly surprised to have the option to switch to another fuel type as a stock feature.

 

 

[Superfluous J]

I hope for the opposite. I hope "Metallic Hydrogen" won't be called that in the game, but will instead be "Metallic Fuel" or something like that so you get a wink and nod and can make some guesses about what it's supposed to be, but there's no doubt it's just as generic and make-believe as Liquid Fuel is.

[paul23]

5 hours ago, SpaceFace545 said:

Liquid fuel could literally be anything and if they are adding metallic hydrogen deuterium and other fancy stuff they should probably split up liquid fuel into kerosene-for some rockets and jets, liquid hydrogen-for advanced rockets and fuel cells, Methane-for cool rocket engines, and hydrazine- for when You just want some plain cancerous fun. What are your thoughts?

There is hardly any reason not not go oxygen-hydrogen unless you take many more complex situations into account. (like being able to store the liquid, on earth). Hydrazine would never ever be used if it didn't need to be used, it has worse chemical efficiency per mass is highly toxic and hard to handle. Then there's the corrosiveness and hence the choice of metals that depend on the fuel. Or how do you model the toxic disadvantages for the environment in a fuel?

If this is then reduced to "you can have fuel xyz with engine abc, and other fuel with other engine", where each engine can have a single fuel. Then what's the difference in just abstracting it away under thrust and specific impulse? 

 

I suggest you'll first read the book "Ignition!" by John D Clark. It shows the choice of liquid fuel.

Edited May 3, 2020 by paul23

[SpaceFace545]

48 minutes ago, paul23 said:

There is hardly any reason not not go oxygen-hydrogen unless you take many more complex situations into account. (like being able to store the liquid, on earth). Hydrazine would never ever be used if it didn't need to be used, it has worse chemical efficiency per mass is highly toxic and hard to handle. Then there's the corrosiveness and hence the choice of metals that depend on the fuel. Or how do you model the toxic disadvantages for the environment in a fuel?

If this is then reduced to "you can have fuel xyz with engine abc, and other fuel with other engine", where each engine can have a single fuel. Then what's the difference in just abstracting it away under thrust and specific impulse? 

 

I suggest you'll first read the book "Ignition!" by John D Clark. It shows the choice of liquid fuel.

That’s what I though the kerbal liquid fuel was cause rockets and fuel cells use it but jet engines just don’t really run on it.

[OOM]

5 hours ago, jimmymcgoochie said:

Generic terms like liquid/solid fuel, oxidiser, electric charge etc. remove a lot of the complexity so new players don't get overwhelmed and also mean the same set of resources can be used everywhere without worrying about what exactly those resources are- they just work. I would be very surprised if that changed in KSP2.

There are plenty of mods for KSP that add different fuel types, from simple stockalike versions of liquid hydrogen and liquid methane to real rocket fuels, so expect similar mods to appear in KSP2 pretty quickly after its release so players who want MOAR REALISM can have the real fuels, players who want some stockalike cryo fuels or additional ion/magnetic engine options can have those and players who are just about able to understand fuel + oxidiser = boom can stick with that and not have to worry about hypergolics and kilowatt-hours etc. etc.

Lol, what's the difficulty? KSP was not originally a game for children ~ 10 years old. Is it really so hard for people to learn ALL 3 possible fuels? 1. Kerosene + oxygen and also High-boiling fuels = this is an analogue of liquid fuel. 2. Hydrogen + oxygen = low density 3. Methane + oxygen = something between 1 and 2. ALL IZI. IZI Do not turn the future masterpiece into some kind of arcade bottom please.
3 types of fuel is not so much. But it gives space for creativity.

Kerosene "liquid fuel", methane and hydrogen should be in the stock game.

"Solid fuel" and "oxidizer" - unchanged.

Spoiler

Kerosene + oxidizer: high density, momentum ~ 289-330
Hydrogen + oxidizer: low density (large fuel tanks required) impulse ~ 400-450
Methane + oxidizer: average density impulse ~ 355

 

Edited May 3, 2020 by OOM

[SpaceFace545]

14 minutes ago, OOM said:

Lol, what's the difficulty? KSP was not originally a game for children ~ 10 years old. Is it really so hard for people to learn ALL 3 possible fuels? 1. Kerosene + oxygen and also High-boiling fuels = this is an analogue of liquid fuel. 2. Hydrogen + oxygen = low density 3. Methane + oxygen = something between 1 and 2. ALL IZI. IZI Do not turn the future masterpiece into some kind of arcade bottom please.
3 types of fuel is not so much. But it gives space for creativity.

Kerosene "liquid fuel", methane and hydrogen should be in the stock game.

"Solid fuel" and "oxidizer" - unchanged.

  Reveal hidden contents

Kerosene + oxidizer: high density, momentum ~ 289-330
Hydrogen + oxidizer: low density (large fuel tanks required) impulse ~ 400-450
Methane + oxidizer: average density impulse ~ 355

 

I so agree with you I just didn’t want to sound rude, if they are going to complicate the game by adding torch ship trajectories and interstellar trajectories they could at least break up liquid fuel into three different fuels. Kerosene, methane, and hydrogen. Plus it would give us a purpose to ship around and stockpile fuels that you can’t mine like kerosene.

[SchwinnTropius]

Based on what I know about the game so far (I guarantee it's less than most), if they do anything with the fuels, I believe they may simply add a new exotic type of fuel for the interstellar engines. It keeps the simplicity of KSP1 but accounts for the new engine type. I do agree that a touch more realism in the fuels would be nice, but I don't see the need to complicate the game further and I feel slightly confident the devs may agree.

[SciMan]

As it is, I believe that the best analog for Liquid Fuel is methane not kerosene, because are jet engines that have been made to use liquid methane, regular rocket engines are being made to use it now, and NTRs could be made to run on methane if you can keep the core temperature high enough that the carbon doesn't build up in the small fuel channels.

[SpaceFace545]

13 minutes ago, SciMan said:

As it is, I believe that the best analog for Liquid Fuel is methane not kerosene, because are jet engines that have been made to use liquid methane, regular rocket engines are being made to use it now, and NTRs could be made to run on methane if you can keep the core temperature high enough that the carbon doesn't build up in the small fuel channels.

But no fuel cells what use hydrogen. It’s probably hydrogen because both nervas and fuel cells use hydrogen

[Drakenred65]

There are fuel cell designs that use methane. The drawback being the creation of CO2 in the process, so they would probably not be used on spacecraft for obvious reasons.

 

and res I know about the molten Carbonate fuel cell. The problem that thing has is it’s weight and operating temp, well that and you still have the problem of it’s wast products.

Edited May 9, 2020 by [email protected]

[desert]

I've had the same thought, we get many new types of future fuel, why not add types of today. But I understand why many players wouldn't like it. So, maybe to have separate option, which is not default in normal game difficulty. In this case new players (who usually choose easy or normal difficulty) will not be overloaded by such things. (Same could be applied to Life Support which many players want to have while others prefer more arcade gameplay)

And then just add kerosene, hydrazine, methane, and hydrogen. Kerosene is for early engines and for most planes, hydrazine for small engines, methane for advanced engines, hydrogen for mostly vacuum-optimized engines and Nerva, as well as fuel cells.

Not sure about oxidizers, probably one is enough. And fuel switch for tanks, of course.

Some kind of base management can be tied to these fuel types, different planets with abundance of different fuels, and each fuel requires special facility to be produced

[SpaceFace545]

6 minutes ago, desert said:

I've had the same thought, we get many new types of future fuel, why not add types of today. But I understand why many players wouldn't like it. So, maybe to have separate option, which is not default in normal game difficulty. In this case new players (who usually choose easy or normal difficulty) will not be overloaded by such things. (Same could be applied to Life Support which many players want to have while others prefer more arcade gameplay)

And then just add kerosene, hydrazine, methane, and hydrogen. Kerosene is for early engines and for most planes, hydrazine for small engines, methane for advanced engines, hydrogen for mostly vacuum-optimized engines and Nerva, as well as fuel cells.

Not sure about oxidizers, probably one is enough. And fuel switch for tanks, of course.

Some kind of base management can be tied to these fuel types, different planets with abundance of different fuels, and each fuel requires special facility to be produced

Oxidizer is oxygen what hopefully is the same

[Drakenred65]

Ok apparently some people think the molten carbonate is a reference to Star Wars. 
 

it’s not 

[SpaceFace545]

9 hours ago, [email protected] said:

Ok apparently some people think the molten carbonate is a reference to Star Wars. 
 

it’s not 

So I can’t freeze any kerbals?

[Drakenred65]

Mods....I suspect

 

[Fraston]

Let’s keep it simple.

It’s been liquid fuel, it should be liquid fuel. Any new normal rocket engines should stick to the gold liquid fuel standard

Only if it’s radically different from everything else should it require it’s own fuel (ion requiring xenon, Orion requiring nukes)

[afafsa]

On 5/15/2020 at 5:17 PM, Fraston said:

Let’s keep it simple.

It’s been liquid fuel, it should be liquid fuel. Any new normal rocket engines should stick to the gold liquid fuel standard

Only if it’s radically different from everything else should it require it’s own fuel (ion requiring xenon, Orion requiring nukes)

Why? What's wrong with deepening some of the mechanics? Oversimplifying things ends removing any reason to build colonies. If you can turn ore into literally anything, what's the point of setting up bases on different planets/moons? Is it really so difficult to figure out that ice can be cracked into hydrolox and water and CO2 can be converted into methalox?

 

This community seems to have an allergic reaction to anything that might accidentally teach them something about space exploration. The average player should be more than capable of learning about even the more nuanced things with a better UI and some decent tutorials. If all you want is a KSP1 with better graphics, I kind of don't see the point.

[mattinoz]

Have to agree the system could happily be more complex than it is currently especially if that opens up design challenges. we are talking what 6 to 10 fuel types up from 4. Adding 3 where there was only one is going to help players ramp up so don’t hit a wall of exotic fuel mechanics at some point in the game.  
 

I’d assume these would make resource collection more interesting to boot.

 

Edit to add - if KSP had a mode like this with different colours for fuel types it would add to the fun. 

https://futurism.com/amazing-vid-rockets-transparent?fbclid=IwAR1s5eaI5WFTTDzKHhRUXoypiMf4wEpQBHD9QK4W6GFoTfylXmVS7Y6s8Vs
 

 

Edited May 17, 2020 by mattinoz

[GluttonyReaper]

Just echoing what others have said earlier, but complexity for complexity's sake is really not helpful, especially in a game that's as already as difficult as KSP. It feels obvious when you've been playing a while, but I've seen quite a few new players trying to, for example, attach a liquid fuel engine to a command pod without any fuel tanks at all, because coming from a gaming background, it's certainly not a given necessity, and if you don't have a background knowledge of spaceflight, it might not be something that immediately occurs to you. This is actually the reason the tech tree starts with a solid fuel engine - because you can just stick that on, and it'll work, which might be the difference between the game catching someone's attention and just shutting it down, never to be played again.

That said, I wouldn't mind different fuel types, but it's important that they be interesting and distinct. In my mind, this is the problem with hydrazine and methalox engines. As far as I can tell, methane is just a slightly worse kerosene/RP-1, with the only really advantage being that it could synthesized off-world easier. Would that even make much of a difference, especially given that by the time a player would be thinking about ISRU, they probably mostly switched over to the more 'advanced' methane engines anyway? In that case, it's not even a real choice - it's not an interesting decision, it's just an outright replacement for kerosene after a point that could easily be just represented by new engines. Hydrazine could be interesting... but the real world benefits of it are that it solves real world problems - namely, it's hypergolic, so it's easier to build multiple-ignition engines using it. This isn't an issue in KSP, given all engines have infinite ignitions anyway, and changing that would add more unnecessary complexity.

Hydrazine also raises another problem - realistic accuracy. Hydrazine doesn't use liquid oxygen as an oxidizer, which could raise more questions than it answers - really, the only thing it's accurately depicting is that hydrazine is a fuel used for small engines. Again, there's a reason KSP uses the generic Liquid Fuel rather than anything specific. By abstracting, you remove the problem of accuracy entirely - any resemblance to real life fuel is entirely coincidental, which is why for the 1.0 release they were able to drop the ISP of every engine in the game by ~50, and allow it to be synthesized from 'Ore' without any major complaints about it being inaccurate.

Anyway, this all sounds really down on alternate fuels, but I would say Liquid Hydrogen is a perfect example of a good one! Having played with Cryo Engines for a bit, it's definitely a fun option. It's more expensive and much less dense than Liquid Fuel, but has a much higher ISP, which makes it plenty distinct enough. But it's also interesting - it has the added issue of boiloff, which makes it impractical for anything beyond the the inner Kerbin system, but you can mitigate it later in the game using more advanced tech to store it indefinitely for long periods of time using electric charge, which even ties into another system. It just feels like a very different fuel, used by a very different class of engine. That's pretty much the gold standard for a fuel type

Oh, and just because there's a little bit of talk about resource gathering going on, here's what the original plan for resources was in KSP1 several years ago: https://i.imgur.com/lGlWdyn.png   

[Bej Kerman]

18 hours ago, afafsa said:

Why? What's wrong with deepening some of the mechanics?

Changing liquid fuel to x is rather pointless and doesn't make the game any deeper. It just makes things more complicated.