Limitless Solar Cruiser - Need help and ideas

[stildawn]

Hi All

I'm very new to KSP, only had it for about a week or 2 but loving it so far. Anyway so I have a space station in HKO which I plan to load up with fuel, and then I plan on trying to design and build a massive Limitless Solar Cruiser, I have read about the Kethane Mining Mod, so my basic idea was to design this cruiser and build it in orbit. It would have a massive fuel capacity, as well as multiple modular craft attached to it for planetary missions.

These are the separate modular craft I'm thinking of:

- Multipurpose Lander (Able to take Kerbals and a Rover down and up again)

- A few satellite probes

- Perhaps a Space Plane for atmospheres that landers are not suited for

Also with the Kethane Mining Mod, I would need a set of modular craft that can perform the mining/orbit transport task. Now I have never tried the mod (will install tonight) but is something like this feasible? Can a mining lander be made that will land, mine and come back with more kethane that it uses? The idea would be that the mother ship can essentially cruise around the solar system indefinitely refueling as it goes.

I have a few other questions relating to this plan:

- Taking into account that the Cruiser will never be required to come into orbit as it will be built in space, what is the most efficient type of engine for space maneuvering (orbit changes, transfers etc)? Would it be worthwhile using the Xeon/Elec engine route instead of the liquid fuel engine route?

- Can Kethane be converted to the xeon gas fuel?

- Is there any sort of mod that helps with orbital construction? I understand the docking mechanics, but I find that docking joints (and joints in general) are rather weak and wobbly? Is there a mod to allow struts to be placed in space or something? I usually strut up my module parts well on the ground, but where they dock together I cant do in the VAB obviously?

- How long does Kethane Mining take? Can it be done of the fly at all? Or does it really require permanent bases?

That's it for now, thanks heaps in advance.

Edited June 30, 2014 by stildawn

[Red Iron Crown]

- Taking into account that the Cruiser will never be required to come into orbit as it will be built in space, what is the most efficient type of engine for space maneuvering (orbit changes, transfers etc)? Would it be worthwhile using the Xeon/Elec engine route instead of the liquid fuel engine route?

The LV-N nuclear engine is the most popular choice for big orbital ships. Ion engines have a higher Isp but much lower thrust, you will need a ton of them and the associated electrical systems to have a practical ship.

- Can Kethane be converted to the xeon gas fuel?

I don't use that mod but my understanding is yes, it can.

- Is there any sort of mod that helps with orbital construction? I understand the docking mechanics, but I find that docking joints (and joints in general) are rather weak and wobbly? Is there a mod to allow struts to be placed in space or something? I usually strut up my module parts well on the ground, but where they dock together I cant do in the VAB obviously?

Kerbal Attachment System has struts that can be installed in space via EVA.

- How long does Kethane Mining take? Can it be done of the fly at all? Or does it really require permanent bases?

Definitely doesn't require permanent bases, if fact that's a bad idea because kethane deposits deplete. You need some components: A kethane drill and tank, a converter to make it into the fuel of your choice, and tanks to hold that fuel. How you distribute them between lander(s) and your mothership is mostly a play style decision (though obviously the drill and kethane tank must go to the surface).

[Kryxal]

I have a kethane drilling ship, it basically consists of the BIG kethane tank, 4 radially-placed T-400 fuel tanks (with fuel lines to the kethane tank), 8 of those tiny engines attached to the fuel tanks via cubic octagonal struts, RCS ports and monopropellant, the smaller kethane converter, the kethane generator (IMPORTANT on outer planets!), a probe core and some solar panels, landing legs and two drills.

On second thought, here's a previous version, fuel lines are a touch different:

[stildawn]

Thanks for the replies.

1. Is the LV-N engine stock? Or is it a mod? What fuel does it use?

2. I guess this isnot relevant if I'm going to use nuclear

3. Awesome thanks I'll check it out, though it sounds hard if I need to do it via EVA haha.

4. I plan on doing the converting on the mother ship to limit the mass required for a lander, hopefully I can make the lander efficient enough to bring lots of raw fuel back.

[Red Iron Crown]

LV-N is stock, it uses regular liquid fuel/oxidizer.

[cantab]

Also with the Kethane Mining Mod, I would need a set of modular craft that can perform the mining/orbit transport task. Now I have never tried the mod (will install tonight) but is something like this feasible? Can a mining lander be made that will land, mine and come back with more kethane that it uses? The idea would be that the mother ship can essentially cruise around the solar system indefinitely refueling as it goes.

Yes, at least for most bodies.

- Taking into account that the Cruiser will never be required to come into orbit as it will be built in space, what is the most efficient type of engine for space maneuvering (orbit changes, transfers etc)? Would it be worthwhile using the Xeon/Elec engine route instead of the liquid fuel engine route?

- Can Kethane be converted to the xeon gas fuel?

These are related. While kethane *can* be converted into xenon, it's not as efficient as converting it into LFO. Kethane>LFO is about a 1:1 mass ratio, but if you convert it to xenon it's about 1:0.4 for the small converter and 1:0.25 for the larger one (yes, the big one is much WORSE at making xenon). Therefore an ion-engined ship will end up not needing much less kethane than a nuclear-engined one. Combine that with the stock ion engines and xenon tanks being ill-suited to big ships, and I'd say go with the LV-Ns.

- Is there any sort of mod that helps with orbital construction? I understand the docking mechanics, but I find that docking joints (and joints in general) are rather weak and wobbly? Is there a mod to allow struts to be placed in space or something? I usually strut up my module parts well on the ground, but where they dock together I cant do in the VAB obviously?

KAS lets you place struts on EVA, while quantum struts gives you gadgets that can strut your craft in flight. In stock a common approach is to design big motherships with "puller" engines mounted radially at the front, rather than at the rear.

- How long does Kethane Mining take? Can it be done of the fly at all? Or does it really require permanent bases?

It's pretty quick. Depends how many drills you take of course, but it's no problem to land a ship, start drilling, timewarp until the tanks are full, stop drilling, and launch. Scanning's the bit that consumes real-world time since you need to be flying the scanner and at a low timewarp or it'll miss bits; I suggest starting scanning then watching some TV or something while it does its stuff. (Or just scan until you find a deposit then go for it, rather than trying to survey the whole body.)

One final gotcha: kethane supplies are finite! A really big miner can drain a whole field in one go, so if you decide to build huge be mindful of that.

[Kryxal]

Actually, I take that smaller converter down to top up my fuel tanks, while it lands easily with quarter-full tanks (for lower-gravity bodies, of course) you need lots of fuel to lift the kethane ... better safe than sorry, and you have the generation anyway for the drills...

[Haze-Zero]

This is mostly personal preference, but you may want to make the Kethane Miner also be the craft that converts your Kethane into fuel. This will be the most convenient, because you can land with half tanks or less and then mine the Kethane, perhaps even converting it into fuel as you mine and then lift off with a full fuel load. What you don't use in your ascent, gets returned to your mother-ship. Depending on your landing skills, you may want to make this craft into a Rover incase you fail to land on a deposit.

Its been covered here, but Kethane works like this.

-You deploy a scanner in an (polar) orbit around a planet at a certain height depending on your scanner. Each one has different ranges, and different power consumptions. A polar orbit will eventually scan the entire body except on moons that are tidally locked to their parent planet.

-After circling a bit, which you can do in the lower speeds of time warps, your scanner will find a deposit.

-Then you will want to deploy your Miner/Converter, which you want to ALSO be equipped with a scanner, to land at the deposit.

-Deploy solar panels, often the bigger the better. Deploy Drills. If you have enough solar power, you can also start converting as you drill. You can Timewarp the whole time you are doing either of these.

-Fill up your tanks on the Lander

-Return to mother-ship

-Refuel mothership and repeat the process to get as much as you need.

Things to Note incase you didn't already know OR Things to consider.

-Eve and Tylo are VERY challenging to land and/or escape from. It is difficult to design landers to land and/or escape from these two bodies and often require specifically made craft for these two bodies. It is possible to (semi-easily) design a lander that can land and escape from every other landable bodies in one multi-purpose craft.

-Eve, Laythe, Kerbin and Duna are the only bodies with atmospheres. A lander with parachutes can land on bodies with atmospheres. While parachutes become useless on bodies without atmospheres, these can be significant weight savings when considering them against the extra weight of Space-Plane.

-Laythe and Kerbin are the ONLY bodies in which Jet Engines work. If you wish to fly your space-plane on Eve, or Duna you will need to rely solely on rocket engines. Your wings will work on these two bodies but not jet engines. Because of this fact, I would recommend that you save the weight and NOT take a space-plane at all. You will only get to really enjoy flying it on 1 other body besides Kerbin.

-IIRC the Kethane Mod (its been a long time since I used it) has a Jet Engine that runs solely on Kethane, no Oxygen required. Though I could be wrong but it maybe worth checking out, if you're intent on having your space-plane.

-The Kethane Convertors follows the REVERSE of fuel-flow rules. This is often confusing to first time users of Kethane.

The Nuclear Engines are certainly the way to go for your mother-ship. You may want to consider using them for your lander as well, but while they are efficient they do not provide much thrust. Depending on how heavy your miner-lander is, you may want to consider 3 or more.

Edited July 1, 2014 by Haze-Zero

[cantab]

-IIRC the Kethane Mod (its been a long time since I used it) has a Jet Engine that runs solely on Kethane, no Oxygen required. Though I could be wrong but it maybe worth checking out, if you're intent on having your space-plane.

Yup, the "KE–J65 Zero Bypass Turbine". It can be pretty efficient, but the gotcha is it has an intake integrated into it and does not work with regular air intakes, so no air hogging.