[WIP] Convair NEXUS - super heavy Earth Launch Vehicle

[TiktaalikDreaming]

Updated version with working Gas Core nuclear thermal rockets and a few options for the second stage.

[KAO]

how are the control thrusters supposed to be put on? they don't seem to align with the round fuel tank bits, or is their alignment still in progress?

I can't wait to see this when it's all done and textured.

[TiktaalikDreaming]

how are the control thrusters supposed to be put on? they don't seem to align with the round fuel tank bits, or is their alignment still in progress?

I can't wait to see this when it's all done and textured.

They did align, but I needed to rotate the tank at one stage by 5degrees due to the support structures. I'll be rotating the torus back, as it's also not aligning with the engine's pipes. I cleverly rotated the whole tank instead of just the meshes I needed to rototate. :-/ I keep meaning to fix it, but always forget.

[stratochief66]

That is beautiful. I hope you keep at it!

[TiktaalikDreaming]

That is beautiful. I hope you keep at it!

It may seem like I'm not keeping at it, but I've been bogged down trying to get landing legs to work. Those big second stage tanks were expected to be re-purposed for moon or Mars colonies, which strongly implies landing them. Thus, enornous legs. Plus my video card died and Unity (editor or player) will not function at all without hardware acceleration enabled in DX.

Video card fixed, but my landing legs are still a bit ........

[KAO]

ah! it's not dead!

Please don't lose hope

[TiktaalikDreaming]

And I think I have legs working. Jeb[us], that took a bit of work.

[TiktaalikDreaming]

ah! it's not dead!

Please don't lose hope

Not dead. Just uploaded 0.9 I think all the basic parts are there now. I want to get the secondary aerobrake/flap type made, then texture stuff before I call it non-beta, but all the parts are basically functional now.

[hraban]

Hello TiktaalikDreaming,

which of the KSP-physics parameters you have bent so your NEXUS project can start at all?

With the standard physics the DeltaV of the main stage is 0.97. Mind you, only the main stage!

Under these circumstances, is not to think of a payload!

[Overlocker]

DeltaV of the main stage is 0.97

I think you mean TWR (Thrust-to-Weight Ratio), Delta-V is the amount of force the fuel and engine can add to the ship. Still, what program did you use to know the TWR? Cause in MechJeb the SLT is not the same as the TWR ...

[hraban]

I think you mean TWR (Thrust-to-Weight Ratio), Delta-V is the amount of force the fuel and engine can add to the ship. Still, what program did you use to know the TWR? Cause in MechJeb the SLT is not the same as the TWR ...

Yep, i mean the TWR / SLT and i use MechJeb. Both, TWR and SLT is to low to success a takeoff. Sorry typo.

[Technical Ben]

That is giantnormouse. Wow.

[TiktaalikDreaming]

Yep, i mean the TWR / SLT and i use MechJeb. Both, TWR and SLT is to low to success a takeoff. Sorry typo.

You should check what else you have installed. I tested this using a stock install of KSP (ie, no other mods), and TWR was definitely not below 1.0

Also check that you placed the control rockets. You'll need four to match original Nexus designs, and I'm pretty sure without them you'll have less than TWR of 1.0.

Base design is much like .

Hopefully you can see the four control rockets spaced around the edge. The base Nexus design has 24,000,000 lbTrust from the main engine and 8,000,000 lbTrust from the control rockets. And 24,000,000 lbs for total weight, so without the control rockets, the TWR is 1.0, aka, going to sit on the launch pad until you've burnt a fair bit of LOX+LH. Skipping the control rockets is like skipping five and a bit SaturnV F1 rockets.

For extra heavy payloads, extra control rockets can get you the TWR to get airborne, although you'll trade delta V for that privilege. I've tried it, and with 6 and a heavy payload you can still get to orbit using stock Kerbin planet sizes. I doubt it'd work on Earth, but it'd be OK for parabolic insertion instead of single stage to orbit.

[TiktaalikDreaming]

Just to let people know: My next update will be to make this Community Resource Pack compliant, and switch to using LOX + LH for the main engines, and LH for the Gas Core Rockets.

I'll also be de-sillying the Blutonium-TetraFluoride nuclear fuel to the actual fuel name (Uranium TetraFluoride aka UF4) to be more in line with CRP, and submitting that fuel for later inclusion. With that, I'll be doing some part/mass adjustments to get it all to match 1/8th of the Convair Nexus-1.

After that release, it's on to texturing.

Then variants. The tailored Nexuses, and Nexus-2 (double mass+payload) and possibly the super-Nexus (bigger again).

[Shad0wCatcher]

I may be mixing my mods (may be KSPI only) but UF4 already exists with its correct density in either CRP or in KSP-Interstellar's implementation.

[TiktaalikDreaming]

I may be mixing my mods (may be KSPI only) but UF4 already exists with its correct density in either CRP or in KSP-Interstellar's implementation.

I've looked through the list for CRP several times, and it has various Uraniums, but no UF4 that I can find. I may just be missing it. I'm guessing then it's in the Interstellar resources. I might double check to be sure (and steal theirs, so I don't have to come up with numbers and so I don't conflict with theirs).

Thanks for the heads up.

Looks like it may just be memory based mixing of data. There's Thorium TetraFluoride and Uranium Nitride, one after the other in the list for the KSPI section of CRP. Both a bit different.

Edited July 7, 2015 by TiktaalikDreaming
Updated info

[TiktaalikDreaming]

I've converted everything I can find (not 100% sure I caught all the engines and tanks) to Community Resource Pack fuels, plus I've added two new fuels for the Gas Core NTRs. Uranium TetraFluoride as the main nuclear fuel, plus a seed for the propellant, Tungsten (again, I was a bit surprised this wasn't already in CRP). Tungsten acts as a neutron and gama ray absorber, as Hydrogen is quite crap at that.

Mass ratio of about 1% with Hydrogen aparently works OK. My first thought was 1% of a 60 foot diameter tank is still going to need some extra parts, but then good old Wolfram vs Hydrogen densities puts the volume ratio at ~0.00004, I can get by with a few tens of litres.

I've set both Tungsten and Uranium tanks to hold quite a bit at max, but the default amounts are a bit over one fuel burn for Tungsten and about twice that for Uranuim. Both can be doubled. So, it's perfectly reasonable to do a one way trip with mining and purification systems to regenerate enough H2 to come back. And for extreme versions, it'd be a lot safer to mine and purify Tungsten than Uranium TetraFluoride. You really don't want to be handling UT4.

Realistically, you probably want to wait a while before exiting a craft that's touched down using these GCRs, even in a vacuum. The exhaust from a mix of UT4, H2, and fission products is not friendly to anyone. Thankfully it's quite reactive and likely to finish coroding what it's going to corode fairly quickly. Leaving just mildly radiactive surfaces.

Anyway, I'm away for a few days, so will upload this when I get back, after I've done more testing than seeing if the GCRs still work on a test bed.

[Gaalidas]

And I thought my posts could make people's heads hurt. I'm gonna need drugs to get over this one.

[kerbiloid]

I've looked through the list for CRP several times, and it has various Uraniums, but no UF4 that I can find.

UF4/Uranium Tetrafluoride was used in original KSPI.

As far as I know, currently its KSPI-Extended fork is the only known alive version of KSPI.

http://forum.kerbalspaceprogram.com/threads/111159-BETA-1-0-4-KSP-Interstellar-Extended-1-2-4-%28last-updated-1-7-2015%29

It is synchronized with CRP. UF4 is replaced with EnrichedUranium - to match with USI and NFT.

[TiktaalikDreaming]

UF4/Uranium Tetrafluoride was used in original KSPI.

As far as I know, currently its KSPI-Extended fork is the only known alive version of KSPI.

http://forum.kerbalspaceprogram.com/threads/111159-BETA-1-0-4-KSP-Interstellar-Extended-1-2-4-%28last-updated-1-7-2015%29

It is synchronized with CRP. UF4 is replaced with EnrichedUranium - to match with USI and NFT.

Ah. Ok, that makes sense. I sent a pm to rover dude asking if that represented UF4, but no reply yet. Uranium metal is very much a different substance with very much different chemical properties though. Most reactors work with different forms with UF4 or UF6 as a waste product, depleted of course.

[TiktaalikDreaming]

Updating to 0.10 with new fuels as previously explained.

[TiktaalikDreaming]

I'm going to step through making the existing parts more complete, one at a time.

Most parts need an actual UV-texture. Most currently just have a generic one colour texture applied per mesh at the moment, and need actual textures. This will bloat out the RAM use a bit, but I'll do my best to keep it sane.

I'll be tidying up any weirdnesses (like the clipping on the flag mesh when you zoom out) and attach nodes etc as I go, so if people have concerns I might not have noticed with the curent release, please let me know.

I'll be applying Community Tech Tree patching. This means the parts will fit the normal tech tree, but if CTT is installed, the parts will shift over to those tech nodes.

[TiktaalikDreaming]

Just another quick update. Most of the genuinely Nexus parts are done, and I redid my rocket nozzles. I have the second stage bits and pieces to do before uploading. The parts are being added to appropriate CTT nodes as I go and I've started adding config for "RealPlume" for the engines etc.

New rocket nozzle in blender.

In game

With plumes!!!

[Shad0wCatcher]

Now that sir, is a gorgeous beast. And apologies for the apparent dating of myself (been using KSP-I since it was first released; completely forgot about the resource swap (names remained) after either Boris (for 0.90) or Freethinker (current). Also I wasn't completely off my rocker!

 REACTOR_FUEL_MODE
{
	name = FissionUF4
	ReactorType = 1
	GUIName = Uranium Tetraflouride
	ChargedParticleRatio = 0.0
	Aneutronic = False
	NormalisedReactionRate = 1.0
	NormalisedPowerConsumption = 1.0
	FUEL
	{
		name = EnrichedUranium
		FuelName = EnrichedUranium
		UsagePerMW = 1.530542611476e-11
		Unit = l
	}
}

EDIT: Granted; that just telling the reactors how much fissionable mass is eaten per unit of power but I knew UF4 still existed in KSP-I...if only in name. I wish I could hop on the internet at my house; still have a 0.90 copy of KSP there with a 0.25 zipped up somewhere. It definitely had UF4 with correct mass when KSP-I had its own resource display (the ping-pong balls while flying over the planet).

Edited July 29, 2015 by Shad0wCatcher

[TiktaalikDreaming]

Now that sir, is a gorgeous beast. And apologies for the apparent dating of myself (been using KSP-I since it was first released; completely forgot about the resource swap (names remained) after either Boris (for 0.90) or Freethinker (current). Also I wasn't completely off my rocker!

 REACTOR_FUEL_MODE
{
    name = FissionUF4
    ReactorType = 1
    GUIName = Uranium Tetraflouride
    ChargedParticleRatio = 0.0
    Aneutronic = False
    NormalisedReactionRate = 1.0
    NormalisedPowerConsumption = 1.0
    FUEL
    {
        name = EnrichedUranium
        FuelName = EnrichedUranium
        UsagePerMW = 1.530542611476e-11
        Unit = l
    }
}

EDIT: Granted; that just telling the reactors how much fissionable mass is eaten per unit of power but I knew UF4 still existed in KSP-I...if only in name. I wish I could hop on the internet at my house; still have a 0.90 copy of KSP there with a 0.25 zipped up somewhere. It definitely had UF4 with correct mass when KSP-I had its own resource display (the ping-pong balls while flying over the planet).

Nice.

I imagine it's usually used on a unit per MW type arrangement, but rockets have their own different whatsit. But thankfully I had a bunch of approximated ISPs and "fuel leakage percentages". 1% by mass of UF4 to H2 is actually quite a small amount of % by volume. Still makes the exhaust into a toxic death gas of course. :-)

PS: I didn't really doubt that it *was* there. I was just unsure if it was still there. :-)