[0.25]KSP Interstellar (Magnetic Nozzles, ISRU Revamp) Version 0.13

[Fractal_UK]

...this would have been exceptionally nice to know BEFORE I got halfway through the R&D tree. Is there any way to alter my tree, or am I now boxed into starting a new tree because there was no mention that the altered tech tree is REQUIRED?

You can delete the tree.cfg file in your [KSP main]/saves/[savegame name] folder, that will give you the option to reselect your tech tree of choice. You won't lose any of your progress in the process.

Note that it's not that that the altered tech tree is required but it is heavily recommended. I do my best to support play with other tech trees but unfortunately since upgrades are a KSPI rather than a stock mechanic, these can only work with one tech tree (or tech trees that use the same node names, such as Medieval Nerd's tree redesign).

Edited January 2, 2014 by Fractal_UK

[Dreadp1r4te]

You can delete the tree.cfg file in your [KSP main]/saves/[savegame name] folder, that will give you the option to reselect your tech tree of choice. You won't lose any of your progress in the process.

Note that it's not that that the altered tech tree is required but it is heavily recommended. I do my best to support play with other tech trees but unfortunately since upgrades are a KSPI rather than a stock mechanic, these can only work with one tech tree (or tech trees that use the same node names, such as Medieval Nerd's tree redesign).

Ah, well. Crisis averted. I was afraid all my progress would be lost.

In any case, thanks for taking the time to respond to me, man. Lots of modding communities I've been a part of before haven't been as... err, friendly. Great job on the mod, even if it is a bit (alot) confusing at first. And thanks to everyone who replied with tips! Now if you'll excuse me, there's a problem of a TWR and ISP to solve, and a nuclear reactor and couple of Kerbals to throw at it.

[Donziboy2]

Ah, well. Crisis averted. I was afraid all my progress would be lost.

In any case, thanks for taking the time to respond to me, man. Lots of modding communities I've been a part of before haven't been as... err, friendly. Great job on the mod, even if it is a bit (alot) confusing at first. And thanks to everyone who replied with tips! Now if you'll excuse me, there's a problem of a TWR and ISP to solve, and a nuclear reactor and couple of Kerbals to throw at it.

Another good thing to do is switch the reactors in the VAB from Uranium to Thorium. It will give you another 27% boost to thrust plus a little more ISP.

Edit...

Did some math on non upgraded reactors. These numbers are in vacuum they are much less on Kerbin.

Calculated the number of panels needed for each reactor size based on 40% of its max output, then added the Reactor+Panels+Rocket Nozzle to get kN/T.

This assume your using the reactors mainly for thrust.

Uf4

62.5cm = 1x 1.25m Inline radiator. 0.6475T, using LF gives 0.3kN of thrust or 0.46kN/T

1.25m = 1x Small Heat Radiator. 3.1T, using LF gives 8.9kN of thrust or 2.871kN/T

2.5m = 11x Small Heat Radiator. 17.7T, using LF gives 111.3kN of thrust or 6.28kN/T

3.75m = 4x Huge Heat Radiator. 58.8T, using LF gives 667.5kN of thrust or 11.35kN/T

3.75m = 4x Huge Heat Radiator. 58.8T, using LFO gives 2472.3kN of thrust or 42.04kN/T <good for getting off the ground, not so good on gas

ThF4

3.75m = 22x Heat Radiator. 63.6T, using LF gives 848.5kN or thrust or 13.34kN/T

Edited January 2, 2014 by Donziboy2

[Dreadp1r4te]

Wow, thanks Donziboy! I saw a post earlier in this thread from Fractal showing some screenshots of the upcoming thermal helper plugin. I'm assuming this is going to be in an update? Or is it a separate add-on I could grab right now? I lucked out, I stuck 4 Huge radiators on my 3.75m craft and she's working like a charm. Good call on that "bigger is better" bit.

Here she is, if you're curious:

I'm rendezvousing with my LKO station, Pinnacle Station, because I... well, I neglected to put RCS tanks on my lander. >.>

I need a sticky pad in KSP, I swear.

[RadHazard]

I was bored, so I did some more work on the wiki. Since lots of people are asking what the purpose of unupgraded fission reactors are, I wrote up a small paragraph about the strengths and weaknesses of low-tech nukes on the reactor page, in addition to the expanded information I added. I also touched up some other pages.

[db48x]

I was bored, so I did some more work on the wiki. Since lots of people are asking what the purpose of unupgraded fission reactors are, I wrote up a small paragraph about the strengths and weaknesses of low-tech nukes on the reactor page, in addition to the expanded information I added. I also touched up some other pages.

These edits are superb!

[db48x]

What next?

Thought of another one; build a fusion-powered plane that can function as a SSTO craft on Eve.

[metalpoetza]

Hi guys - I've finished a first pre-release of my KSP_Interstellar missions for KSP_StoryMissions. https://github.com/ajventer/ksp_stuff/releases/tag/0.0.4 this is still very early WIP - currently comprising a single mission chain built around using the thermal rockets with nuclear reactors (on the basis that they were the first major parts I unlocked) it currently ends with using one to do a fly-by of Duna.

I have been looking in more detail at these rockets (and how their values change if you swap fuels) and I suspect it's possible to use them to build a single rocket that can take off from Kerbin (using LFO most likely) ditch the extra fuel, use pure liquid to get to Duna and then use LFO to land and take off - and pure liquid to get back again. This may take a great deal of skill and planning and thus far I haven't managed to do it myself even in Sandbox mode (and I don't want to write a mission for something until I'm sure it can be done - and how feasible it is). The biggest difficulty being the weight of the reactor+rocket for landers (if you don't undock from your liquid fuel tank - it's even worse of course).

That said - I thought I would release the current work as a pre-release for comments and suggestions from the players and developers - this may be as far as this chain goes - the next may be focussing on antimatter detection instead. If you would like to help with these or contribute some missions to it, please feel free to send me a pull request with your changes. If you have ideas you think would help, please feel free to reply to my post and let me know.

[Donziboy2]

Hi guys - I've finished a first pre-release of my KSP_Interstellar missions for KSP_StoryMissions. https://github.com/ajventer/ksp_stuff/releases/tag/0.0.4 this is still very early WIP - currently comprising a single mission chain built around using the thermal rockets with nuclear reactors (on the basis that they were the first major parts I unlocked) it currently ends with using one to do a fly-by of Duna.

I have been looking in more detail at these rockets (and how their values change if you swap fuels) and I suspect it's possible to use them to build a single rocket that can take off from Kerbin (using LFO most likely) ditch the extra fuel, use pure liquid to get to Duna and then use LFO to land and take off - and pure liquid to get back again. This may take a great deal of skill and planning and thus far I haven't managed to do it myself even in Sandbox mode (and I don't want to write a mission for something until I'm sure it can be done - and how feasible it is). The biggest difficulty being the weight of the reactor+rocket for landers (if you don't undock from your liquid fuel tank - it's even worse of course).

That said - I thought I would release the current work as a pre-release for comments and suggestions from the players and developers - this may be as far as this chain goes - the next may be focussing on antimatter detection instead. If you would like to help with these or contribute some missions to it, please feel free to send me a pull request with your changes. If you have ideas you think would help, please feel free to reply to my post and let me know.

LFO and Thorium, your still going to need some boosters to get it up.

[Fractal_UK]

I saw a post earlier in this thread from Fractal showing some screenshots of the upcoming thermal helper plugin. I'm assuming this is going to be in an update? Or is it a separate add-on I could grab right now?

The thermal mechanics helper is going to be part of the next update.

[kendoka15]

I've made a ship currently in orbit around Kerbin and it is powered by a 3.75m Gas core reactor. It has 8 Huge Heat Radiators (all deployed). The WasteHeat first went up, then stabilized, then started to go down, then stabilized, and now it won't go down anymore. Is this normal?

Edit: Nevermind, I figured it out.

Edited January 3, 2014 by kendoka15

[InfinityArch]

So I'm trying to calculate whether it's possible to build a SSTO spaceplane on Eve using KSPI technology, any idea what top speed I could expect to get using thermal turbojet in atmospheric mode, and what TWR I'd need to get into orbit after switching said jets into LFO burning mode? I'm planning on using the unupgraded fusion reactors, given that even with a generator attached to give them power, they weight significantly less than fission reactors thanks to their fuel being the lightest element in the universe.

I'm going to be using FAR by the way.

I've already calculated that trying to get a TWR greater than 1 in LFO mode on Eve would give me slightly less than 1 ton per engine (including fuel!), so a TWR>1 design in rocket mode (which would, in an ideal ascent, be activated when the maximum thrust of the atmospheric mode rockets dropped below that of the LFO mode) is out of the question.

Edited January 3, 2014 by InfinityArch

[Fractal_UK]

So I'm trying to calculate whether it's possible to build a SSTO spaceplane on Eve using KSPI technology, any idea what top speed I could expect to get using thermal turbojet in atmospheric mode, and what TWR I'd need to get into orbit after switching said jets into LFO burning mode? I'm planning on using the unupgraded fusion reactors, given that even with a generator attached to give them power, they weight significantly less than fission reactors thanks to their fuel being the lightest element in the universe.

I'm going to be using FAR by the way.

I've already calculated that trying to get a TWR greater than 1 in LFO mode on Eve would give me slightly less than 1 ton per engine (including fuel!), so a TWR>1 design in rocket mode (which would, in an ideal ascent, be activated when the maximum thrust of the atmospheric mode rockets dropped below that of the LFO mode) is out of the question.

I'm not sure if it's possible in all honest, I've never tried it, I'd guess it isn't possible without FAR but with it, I don't know, you might manage. The velocity curve of even the unupgraded fusion reactors won't stop you until ~3000m/s but it's all about thrust and availability of intake air that will actually determine the real speed you can achieve. I guarantee you'll be able to get high into the atmosphere but I'm not sure how fast you'll be able to go while doing it.

You might be able to do it by augmenting your thrust with a few extra rockets that you use for the boost up from the mid-atmosphere once you need to transition from atmospheric flight. The key is getting enough altitude for long enough that your fusion rocket has time to push you into orbit.

[Haarlock]

Firstly, I'd just like to say that this is a great mod. It's become one of the core mods that I use with KSP.

However, I do have an issue with refueling my nuclear reactors. I've looked around on the wiki, and here to a degree (but 500+ pages is alot and I can't seem to find what I'm looking for with the search function).

Despite having access to more uranium and/or thorium on any given ship, and having a reprocessing plant actively working to remove actinides from the reactors, they all seem to just 'give out' after a long time. I understand that in order to fire a reactor back up, you have to go EVA, wait for it to cool, then right click and Restart Manually. However, no matter where I seem to place the uranium/thorium pods on a ship, I can never actually get the reactor to use up the fuels in there. They will receive 'depleted fuels' from the reprocessing plant, but even then the reactor never takes from the pods themselves. I've tried attaching fuel lines in and out from the pods to the reactor, I've tried docking ports, I've even slapped pods onto the sides of the reactors themselves, and no matter what the thing never seems to use the pods' fuel.

So I guess to sum up my question... how do I use a uranium and/or thorium pod to refuel a reactor?

Thanks in advance, and apologies if this has already been covered in this thread, but I couldn't find anything detailed on how to do it.

[Donziboy2]

So I'm trying to calculate whether it's possible to build a SSTO spaceplane on Eve using KSPI technology, any idea what top speed I could expect to get using thermal turbojet in atmospheric mode, and what TWR I'd need to get into orbit after switching said jets into LFO burning mode? I'm planning on using the unupgraded fusion reactors, given that even with a generator attached to give them power, they weight significantly less than fission reactors thanks to their fuel being the lightest element in the universe.

I'm going to be using FAR by the way.

I've already calculated that trying to get a TWR greater than 1 in LFO mode on Eve would give me slightly less than 1 ton per engine (including fuel!), so a TWR>1 design in rocket mode (which would, in an ideal ascent, be activated when the maximum thrust of the atmospheric mode rockets dropped below that of the LFO mode) is out of the question.

It should be possible, as long as your not trying to lift 100T of fuel:P

Remember Eve has a much thicker atmo at sea level, your still going to have to try it.

Usually in Kerbins atmo depending on how your TWR is you may get to 20-25Km.

I may hyperedit in a plane later and see what happens.

Edit also, most of my craft never have a TWR of 1 or more, at sea level they will be around 0.6, once you hit high altitude it will drop fast. Most of my SSTO's I usually make sure I can do 4-5ms@ 35Km. Which is usually plenty.

[Domfluff]

I am really enjoying this mod. It gives meaning to parts that are usually under utilised (the massive wheels, for example), and most of everything works the way it's supposed to, with appropriate drawbacks and everything. I'm still not sure how I feel about the inclusion of an Alcubierre drive, nor the harvesting of antimatter, really, but the rest of it is amazing. I haven't unlocked those in career mode, so for all I know it might not feel like cheating by then.

It actually feels very similar to playing the boardgame High Frontier, which is no faint praise indeed.

I really like how ISRU is handled - my problem with Kethane is that it's too simple - in reality, a methane rocket is fantastic for Mars... but that's all. That's a major limitation when your scope is "the entire solar system".

A few thoughts:

I've been running a Mun base (surface labs are great, and using TAC life support means that it doesn't feel overpowered to grind science points from a pair of labs, since I have to keep resupplying them), and trying to run an aluminium rocket. I landed a surface refinery, and hooked it up with KAS's pipe parts... but I can't transfer the electrolysed aluminia products across docked ships Currently, to make this work I've had to land a second hybrid rocket with a couple of refineries attached (with fuel lines), so that this could mine Alumina, convert it into fuel, then transfer to the refinery-less rocket for return. Lugging around a refinery on the rocket seems less than optimal...

I know you mentioned solar sails, but what about a Mass Driver? As a propulsion system, rather than the Heinlein ground-based track. Atomic Rockets has the following stats for a typical system: Thrust Power 0.3 GW Exhaust Velocity 30,000 /s Thrust 20,000 N Mass 150 tons Power required 350 MW Efficiency 90%

It might require something like the Project Orion code to simulate continuous impulses though, which might be a big ask. Speaking of which, Orion would fit in very well. The chief advantage of a Mass Driver, of course, is that it's propellant is regolith, so you can fill it up anywhere. It would be ideal for Jool's outer moons, Gilly and Ike at this stage, despite the low thrust and high mass. Clearly it's an interplanetary engine.

If there could be a decent Sail implementation (I honestly don't know how that's doable with the current time warping), then laser propulsion would be the obvious upgrade, and would work much like the microwave transmitters.

I agree with Scott that the current ISRU implementation is difficult to use well/realistically. The best solution I've found so far is mounting a pair of refineries on the radial attachment points, rotated through 90 degrees (so that they sit vertically, half inside the rocket). This works well, but looks pretty terrible, like an aluminium hybrid rocket has a pair of tortoise shells... you can use the quad couplers to make a near-sphere, similar to Discovery. Still doesn't make sense, but at least it looks better

In all, this is an excellent mod, and can only get better. It's satisfying to see that KSP is enough of a simulation to support this kind of additions without breaking everything - using real-world values for Isp and the like, and ending up with real-world engineering problems and solutions. Thank you!

[RadHazard]

Firstly, I'd just like to say that this is a great mod. It's become one of the core mods that I use with KSP.

However, I do have an issue with refueling my nuclear reactors. I've looked around on the wiki, and here to a degree (but 500+ pages is alot and I can't seem to find what I'm looking for with the search function).

Despite having access to more uranium and/or thorium on any given ship, and having a reprocessing plant actively working to remove actinides from the reactors, they all seem to just 'give out' after a long time. I understand that in order to fire a reactor back up, you have to go EVA, wait for it to cool, then right click and Restart Manually. However, no matter where I seem to place the uranium/thorium pods on a ship, I can never actually get the reactor to use up the fuels in there. They will receive 'depleted fuels' from the reprocessing plant, but even then the reactor never takes from the pods themselves. I've tried attaching fuel lines in and out from the pods to the reactor, I've tried docking ports, I've even slapped pods onto the sides of the reactors themselves, and no matter what the thing never seems to use the pods' fuel.

So I guess to sum up my question... how do I use a uranium and/or thorium pod to refuel a reactor?

Thanks in advance, and apologies if this has already been covered in this thread, but I couldn't find anything detailed on how to do it.

Fission reactors have to be refueled manually. You have to shut down the reactor, wait for it to cool, and then use a kerbal on EVA to right click and select the "refuel" option. This option should be available as long as you have enough fuel of the correct type and the reactor isn't completely full of actinides.

[InfinityArch]

Quick question: Will a radial intake attached to a precooler benefit from said cooling unit?

[Lightwarrior]

Simple question - is there any way to disable precooler mechanic? This thing is really game breaking because it forces to place lots of big and ugly parts on spaceplanes, and without this even stock crafts will not work.

I understand that it is "more realistic", but... intakes are totally unrealistic anyway (with those "place anywhere"), and this is defenitely "not fun".

[Donziboy2]

Behold the Lift Masta!

Able to put 306T of fuel and monoprop into LKO. It will only cost you 40.6T of fuel to get there and only weights 511.4T on the runway.

Main body welded to reduce part count, total only 115 parts. Uses 8x 2.5m Fission Reactors.

[Fractal_UK]

Quick question: Will a radial intake attached to a precooler benefit from said cooling unit?

Not at present - still split on whether to add something for radial intakes.

Simple question - is there any way to disable precooler mechanic? This thing is really game breaking because it forces to place lots of big and ugly parts on spaceplanes, and without this even stock crafts will not work.

I understand that it is "more realistic", but... intakes are totally unrealistic anyway (with those "place anywhere"), and this is defenitely "not fun".

There isn't, I guess I'll add an option in the .cfg in the next update. That said, it doesn't by any stretch stop SSTOs working without them, it's trivial to build a spaceplane that switches to LiquidFuel/LFO just before the maximum temperature threshold is hit. You will spend more fuel doing it this way but that's part of the tradeoff.

I've been running a Mun base (surface labs are great, and using TAC life support means that it doesn't feel overpowered to grind science points from a pair of labs, since I have to keep resupplying them), and trying to run an aluminium rocket. I landed a surface refinery, and hooked it up with KAS's pipe parts... but I can't transfer the electrolysed aluminia products across docked ships Currently, to make this work I've had to land a second hybrid rocket with a couple of refineries attached (with fuel lines), so that this could mine Alumina, convert it into fuel, then transfer to the refinery-less rocket for return. Lugging around a refinery on the rocket seems less than optimal...

Fuel lines (and things that function like fuel lines) are the key to making this work. If you can fuel line to a docking port and then connect to that, you should be able to get a good connection - I'm not exactly sure how KAS pipes work with respect to fuel transfer.

know you mentioned solar sails, but what about a Mass Driver? As a propulsion system, rather than the Heinlein ground-based track. Atomic Rockets has the following stats for a typical system: Thrust Power 0.3 GW Exhaust Velocity 30,000 /s Thrust 20,000 N Mass 150 tons Power required 350 MW Efficiency 90%

It might require something like the Project Orion code to simulate continuous impulses though, which might be a big ask. Speaking of which, Orion would fit in very well. The chief advantage of a Mass Driver, of course, is that it's propellant is regolith, so you can fill it up anywhere. It would be ideal for Jool's outer moons, Gilly and Ike at this stage, despite the low thrust and high mass. Clearly it's an interplanetary engine.

It's certainly a possibility - it needs quite a unique model which is a major stumbling block, the code is less of an issue. I'd like to implement "regolith refueling" though.

If there could be a decent Sail implementation (I honestly don't know how that's doable with the current time warping), then laser propulsion would be the obvious upgrade, and would work much like the microwave transmitters.

I did some work on it but ran into some problems with numerical stability when trying to edit orbits during high timewarp. I don't know if I can solve it but I'll probably come back to it at some stage.

I agree with Scott that the current ISRU implementation is difficult to use well/realistically. The best solution I've found so far is mounting a pair of refineries on the radial attachment points, rotated through 90 degrees (so that they sit vertically, half inside the rocket). This works well, but looks pretty terrible, like an aluminium hybrid rocket has a pair of tortoise shells... you can use the quad couplers to make a near-sphere, similar to Discovery. Still doesn't make sense, but at least it looks better

Yeah, I actually tried to do some work on a 2.5m inline refinery model myself to address this issue but the result was pretty horrendous. Making a decent texture for a simple part is unfortunately beyond me!

I'm still not sure how I feel about the inclusion of an Alcubierre drive, nor the harvesting of antimatter, really, but the rest of it is amazing. I haven't unlocked those in career mode, so for all I know it might not feel like cheating by theny

It actually feels very similar to playing the boardgame High Frontier, which is no faint praise indeed.

The late game is sort of like the expanded high frontier late game, it's a totally different challenge by that point, it's all about having sufficient infrastructure, in this case to maintain your supply of advanced resources. I don't have anything that would quite qualify as a "Terawatt Thruster" but some of those parts get close. The Alcubierre drive can be a bit of a mixed blessing, very useful once you figure out how to use it but liable to leave you with 15km/s burns until you do.

In all, this is an excellent mod, and can only get better. It's satisfying to see that KSP is enough of a simulation to support this kind of additions without breaking everything - using real-world values for Isp and the like, and ending up with real-world engineering problems and solutions. Thank you!

Thanks for the feedback and glad you're enjoying it so far!

[InfinityArch]

On a side note Fractal, is it realistic that you still need precoolers for intakes feeding thermal turbojets, especially ones using intertial fusion or gas core nuclear reactors to heat the atmospheric intake? That's so far been the biggest barrier to my attempt to make an Eve SSTO.

[Lightwarrior]

There isn't, I guess I'll add an option in the .cfg in the next update. That said, it doesn't by any stretch stop SSTOs working without them, it's trivial to build a spaceplane that switches to LiquidFuel/LFO just before the maximum temperature threshold is hit. You will spend more fuel doing it this way but that's part of the tradeoff.

It would be nice.

Yes, such spaceplanes can be built, but they most likely will never go beyond kerbin orbit without refuel.

And BTW those R.A.P.I.E.R. engine, if it is designed based on real Sabre engine, already have integrated precoolers.

Also how will those thermal turbojets, being heated by reactors with 15k+ core temperature, will overheat from atmospheric friction?

Edited January 3, 2014 by Lightwarrior

[Shad0wCatcher]

Infinity: No matter the type of combustion system, pre-cooling air always helps; cooler air means denser air which means more fitting into the combustion chamber before expulsion.

[InfinityArch]

@Shad0w: I suppose it helps, though for nuclear turbojets I imagine the issue would be loss of thrust at high air speeds rather than the engine overheating.