Stockalike RF Engine Configs v3.2.6 [01/20/19][RF v12]

[Starwaster]

In Fuel_Conversions.cfg, don't reference amount. Use maxAmount instead. Several parts have 0 amount of a resource. (done so that a part CAN be filled but by default is empty)

The end result is that ModuleFuelTank is configured with volume = 0

This is very bad because it results in parts with zero thermal mass which is totally cross the streams bad. (parts explode the first frame after loading into the world)

[Raptor831]

Ah, that is bad. I'll change that up ASAP.

The new thermal system seems to be attracting bugs recently...

EDIT: I've updated Fuel_Conversions.cfg to use maxAmount instead of amount on the repo. It'll be in the next "release", but if you want to test it out it's there.

Edited June 27, 2015 by Raptor831

[Starwaster]

There are %flowMode = STAGE_PRIORITY_FLOW entries in the PROPELLANT nodes inside the ModuleEngineConfigs.

These need to be %ResourceFlowMode = STAGE_PRIORITY_FLOW

(flowMode doesn't work, or doesn't work anymore....)

[Raptor831]

There are %flowMode = STAGE_PRIORITY_FLOW entries in the PROPELLANT nodes inside the ModuleEngineConfigs.

These need to be %ResourceFlowMode = STAGE_PRIORITY_FLOW

(flowMode doesn't work, or doesn't work anymore....)

Noted. On my list to fix.

[Requia]

Why did you up the weight of the LV-N when it's already unrealistically heavy (compared to thrust) in stock (apologies if that belongs to the original RF configs)

[Requia]

Ok, if i turn realistic mass to false the LV-N jumps to over 17 tons. I'm guessing this is a bug and not a feature.

[Requia]

Ok realistic mass complaint removed now that I get tech level is a gui thing not a reflection of how much tech has been unlocked. But reverting to stockish masses still murders it.

Edited July 2, 2015 by Requia

[NathanKell]

Ah, but that just means the LV-N is playing by the same rules as the other engines.

See, in stock KSP, the regular liquid engines have about 1/4 to 1/6 the TWR that real ones do. However, the LV-N has about its real TWR (maybe 2/3 now that the mass is 3t). So if it plays by the same rules as regular KSP engines, it masses a lot.

tl;dr LV-N is OP compared to regular engines, RF makes it play by the same rules.

[Requia]

Where the heck are you getting your numbers? The NERVA (which is a good spec point for minimum tech to launch) specs a TWR of ~5, the stock LV-N has a TWR of 2, your 'realistic' config has an entry TWR ~1.25 of your stockalike LN-V config has an entry TWR of .36.

[NathanKell]

NERVA 2 was about 7.45, NERVA Alpha about 2.86, NERVA Gama 3.4, and RD-0410 was 1.8 (all via astronautix).

TL4 or TL5 corresponds to the mid-late 70s NERVA. TL3 is mid-60s tech. Since RF engines generally include extra mass for the thrust frame, the engine-only TWR will be something like 10 to 15% higher, so correcting for that the TL4 TWR is about 2.2 and the TL5 TWR is about 2.7, a bit low for US engines but high for Soviet.

[Requia]

If TL3 is mid 60s it shouldn't be possible to make it at TL3. Its not until the early 70s that it was actually an option. The NERVA-2 is the FIRST engine that could conceivably have been built, those 60s tests shook themselves apart and vented their reaction mass with the exhaust.

But regardless, I would really like USABLE configs that are meant for Kerbol and not RSS. 17 ton engines don't factor into that.

I've figured out how to change the realistic masses, still can't find the stockalike masses, is it just a multiplier?

Edited July 2, 2015 by Requia

[Raptor831]

If TL3 is mid 60s it shouldn't be possible to make it at TL3. Its not until the early 70s that it was actually an option. The NERVA-2 is the FIRST engine that could conceivably have been built, those 60s tests shook themselves apart and vented their reaction mass with the exhaust.

But regardless, I would really like USABLE configs that are meant for Kerbol and not RSS. 17 ton engines don't factor into that.

I've figured out how to change the realistic masses, still can't find the stockalike masses, is it just a multiplier?

The problem with stock LV-N was that it was massively under-massed compared to real NTR engines. Squad bumped the mass in 1.0, but it's still comparatively light.

This set of config aims to bring realistic mass, thrust, and fuels to stock(ish) KSP. Since it's using corrected TWR, it feels overpowered (generally) compared to stock, with the exception of the NTR engines. Those now feel massively underpowered thanks to their mass. But this is more accurate. NTRs (especially low TL ones) can only be used as orbital engines. And they'll cost you a lot to get them into orbit. Once you get to TL 7 and 8, though, the mass comes way down. The TWR is around 8 times higher compared to TL3, and most of that is mass savings (IIRC).

If you don't like that balance, set the useRealisticMass back to true, and use Kerbal Isp Difficulty Scaler (KIDS) to adjust the Isp down to something that feels right for your preferred game. I've built these while playing on a 6.4x stock scale. Since stock parts are about 64% the size of their real counter parts, and Kerbin is about 1/10th the size of Earth, you end up with a great fit. If that's not what you like, KIDS should be able to scale it for you.

[Requia]

No it isn't. The LV-N is lighter than NERVA-2 would have been, but its also a fraction of the power. It's substantially heavier than the LV03, which is the most complete system (actually built, never finished testing) since the 70s, and *still* a fraction of the power.

But maybe you could explain how the configs work and I can change JUST the NTR (and also whatever else I find, the Mammoth also has issues but its not as big a deal), instead of trying to change every other engine in the game?

[Starwaster]

No it isn't. The LV-N is lighter than NERVA-2 would have been, but its also a fraction of the power. It's substantially heavier than the LV03, which is the most complete system (actually built, never finished testing) since the 70s, and *still* a fraction of the power.

But maybe you could explain how the configs work and I can change JUST the NTR (and also whatever else I find, the Mammoth also has issues but its not as big a deal), instead of trying to change every other engine in the game?

Let me just be sure I have this straight:

You want useRealisticMass = false (for RealFuels) but you don't want the mass multiplier to affect the LVN or you want a different mass multiplier for it, correct?

When useRealisticMass is set to false, engineMassMultiplier (= 4) is applied to all engines

So either change the global to suit what you want for all engines

OR

(I think this is what you actually want)

EDIT: Removed advice where I had you editing original Stockalike_Squad.cfg file - don't do that. Use a Module Manager patch instead

@PART[nuclearEngine]:FINAL
{
	@MODULE[ModuleEngineConfigs]
	{
		@CONFIG[NTRLqdHydrogen]
		{
			massMult = 0.25			
		}
		@CONFIG[NTRLqdAmmonia]
		{
			massMult = 0.25			
		}
		@CONFIG[NTRLqdMethane]
		{
			massMult = 0.25			
		}
	}
}

That completely counteracts the x4 multiplier being applied to the engines. I did each config separately instead of blanketing with a wildcard. You can change massMult to suit yourself for each engine config.

Edited July 2, 2015 by Starwaster

[Requia]

Yes that's exactly it, it gives performance much closer to the stock LV-N. Thanks

Why a modulemanagerpatch instead of direct edit?

[Tellion]

Because the MM patch you can drop into your "patches" folder and effortlessly remove should you want to try something else. If you forget direct edits, you might have quite the headache trying to figure out why things do not behave as expected

[Starwaster]

Yes that's exactly it, it gives performance much closer to the stock LV-N. Thanks

Why a modulemanagerpatch instead of direct edit?

What Tellion said but let me expand just a bit. Updates happen. Sooner or later you're going to have to do a complete reinstall of one thing or another. (or all of them). If you have to reinstall RealFuels and Stockalike RF configs and let's say that Stockalike added some things and fixed broken configs, then you have to update. Maybe after the time that's passed you remember what you changed or maybe you don't.

I have a folder called MyTweaks full of MM patches. Everything I've ever decided to change about my installation over the years and it's usually the first thing that gets installed after Module Manager. I don't have to bother about re-editing this config or that. Easily added. Easily removed.

[TeeGee]

Hi everyone! Just out of curiosity, Ive been trying to find and delete Mon-Hydrazine CFG in the stockalike RF folder to delete it because I don't want to use hydrazine in the place of monopropellant on my craft (due to the fact I would like to be able to use RCSsfx) but I can't seem to find it.

Has it been renamed or ignored in the recent updates? Because even though it isn't in the folder, my craft are still arranged to use hydrazine in the place of monoprop on my craft particularly in stock ven revamp.

[Raptor831]

Hi everyone! Just out of curiosity, Ive been trying to find and delete Mon-Hydrazine CFG in the stockalike RF folder to delete it because I don't want to use hydrazine in the place of monopropellant on my craft (due to the fact I would like to be able to use RCSsfx) but I can't seem to find it.

Has it been renamed or ignored in the recent updates? Because even though it isn't in the folder, my craft are still arranged to use hydrazine in the place of monoprop on my craft particularly in stock ven revamp.

That piece is now in Fuel_Conversions.cfg (link on GitHub). If you remove that, anything not specifically set up to use hydrazine will still use MonoProp. There's not a nice MM way to do this, that I know of. Currently the conversions all are on the :Final pass, so there's nothing that can be run after them.

If it's the RCS plugin from pizzaoverhead, then the plugin is only going to work with ModuleRCS items. Anything that uses ModuleRCSFX won't work. Which is every RCS that's set up for this config. Do Ven's RCS parts use ModuleRCSFX or ModuleRCS?

[NathanKell]

Sorry to say this, but your EI configs are broken (and probably have been since the start).

Inside a CONFIG, you need a ModuleEngineIgnitor {} node, not a MODULE node.

Note that once you fix that, RF 10.4+ will notice those configs as well, so you get limited ignitions and ullage on 1.0.4 with RF 10.4+ without EngineIgnitor.

[TeeGee]

Sorry to say this, but your EI configs are broken (and probably have been since the start).

Inside a CONFIG, you need a ModuleEngineIgnitor {} node, not a MODULE node.

Note that once you fix that, RF 10.4+ will notice those configs as well, so you get limited ignitions and ullage on 1.0.4 with RF 10.4+ without EngineIgnitor.

Ya I was just going to notify the thread this as well Nathan. The engine ignitor script which is now included in real fuels requires a overhaul in stockalike scripts for all the engines. As of right now, there is no ullage or limited ignitions in this engine pack.

Just fyi everyone!

[Svm420]

Would anyone have a basic guide to ignition rule for engines. I am curious as I frequently am setting up new engines for new mods and never know what amount to use.

[NathanKell]

TeeGee: that's not quite right. As I said, RF _is_ backwards compatible with EngineIgnitor configurations done inside ModuleEngineConfig CONFIG nodes. Which RF Stockalike does do. It just has a persistent typo which means they've never worked as such.

So no, RF Stockalike does not require an overhaul to make its ignitions and ullage compatible with RF 10.4+; it merely needs the typo corrected, and that typo has nothing to do with changes in RF.

Svm420: Generally speaking, by role/era:

1. Early engines have one ignition.

2. Lifter engines have one ignition, unless they're meant to land returning stages (there's no technical reason these days they can't have multiple ignitions, it's cost/mass saying only one).

3. Upper stage engines used as second stages (not for final orbital insertion or BLEO operations) have one igniton. C.f. Titan LR91 or Proton's second stage. But see 2.

4. Upper stage engines used for orbital insertion these days have multiple ignitions. Merlin 1D Vac is an example, as is RL10 or the RD-58 on Blok D. This is because it's often more efficient to make multiple burns to orbit. These engines often also serve for BLEO orbital injection (GTO, trans-lunar, escape) where you want to have a parking orbit first.

5. Orbital maneuvering engines generally have lots of ignitions.

By propellant type and cycle:

Engines with hypergolic propellants don't have to worry about igniting their propellants in the combustion chamber. Pressure-fed engines don't have to worry about spinning up their turbopumps when there's no combustion going on, they just open the valves. For this reason, most orbital maneuvering engines are pressure-fed hypergolic engines, and pretty much all RCS is either that or pressure-fed monopropellant (needs at most catalyzing)--there's no real difference between, say, the Lunar Module's ascent engine and its RCS other than size and chamber pressure.

Engines that don't have hypergolic propellants, even if they're pressure-fed, have to worry about ignition, either a limited supply of hypergolic ignition cartridges, or a spark plug.

Engines that are pump-fed have to worry about somehow starting their pumps (which requires starting their generators/preburners) before fuel flow. That's possible, but it's much more complex than "open the valves."

tl;dr lifter engines have 1 ignition except in rare cases; upper stages have 1-3 or so, or, if reused as orbital taxis, 3-15. Pressure-fed hypergolic orbital engines often have effectively unlimited ignitions.

NOTE: All the above are subject to ullage.

It is a myth that Just. Won't. Die. that pressure-fed engines don't have to worry about ullage. They do, except in the rare circumstances where their propellant tanks are small enough (and the need to have them work sans ullaging great enough), like RCS, that there's actually a membrane in the tank to separate the propellant and the pressurant.

So yes, the Apollo SPS (and the LMDE and LMAE) were subject to ullage concerns, despite being pressure-fed hypergolics. Their RCS were fed from tanks with membranes, and that's why the RCS didn't have to worry about ullage, not because of pressurization.

The differences are:

Normal tanks (pressurized to around 2atm): needs ullaging, works only with pump-fed engines

Highly-pressurized tanks for pressure-fed engines (much higher pressurization): needs ullaging.

Membrane (or surface-tension, another method) tanks with highly-pressurized propellants: small, heavy, but don't have to worry about ullage.

Edited July 5, 2015 by NathanKell

[allenby]

I tried the suggested ModuleEngineIgnitor edit on a few of the Stockalike engines and can't seem to get ignition/ullage to appear in-game. I edited the ignitor module sections under each CONFIG node. Is there something else that needs to be changed? Is it working for anyone else?

[Svm420]

Would correct ratios for fuel mixtures be able to be added to the eng configuration generation site. So that when you and add a fuel type configuration it defaults to the correct ratio. It a lot more work right now I either have to memorize a ton of fuel mixture ratios or look them up every time. I love the site have used it a ton as new mods have come out and I add them to my install for real fuels. Also I think RCS maybe glitched in that all fuel types are giving equivalent thrust. They used to vary a bit depending on ether it was bi or monopropellant.

Edited July 5, 2015 by Svm420