Interplanetary SSTO with nerv engines

[jsisidore]

15 hours ago, Val said:

I updated the Triana with new landing gear that doesn't explode and made a boring video of the launch.

It shows that the craft has no issue going at 1000 m/s at 10 km, while climbing and accelerating.

(Video should be done uploading and processing 2 hours after posting this. I have to go to bed.)

That was a mad video, clearly you were imagining yourself sitting inside the cockpit  I envy your setup, everything is so pretty.

Things I noticed:

Your take off was far more quicker than mine, are your specs are still the same? I want to compare.

You don't need the help of nukes to break sound barrier and you reach mach 3 while below 10km, I didn't know that!

You still have heaps of fuel left and I bet you can go to Duna with that.

[Val]

2 hours ago, jsisidore said:

I've installed the engineer mod thingy and I think that I'm too heavy. Anyway, my design is impossible to achieve the orbit.

It weighs less than the Triana, so I don't think that's an issue. I think, it has too much drag.

You'll need the big wings if you're planning on going to Duna, so the only optimization I can think of there is, to use fewer, but larger parts to reduce flex and the need for struts.

These are things you want to avoid, in this prioritized order.

• Struts and Fuel lines.
• Externally mounted Solar panels, batteries, antennas and other utilities that could be placed in a cargo bay.
• Excessive RCS blocks. On sub-50 t crafts, you only need 6 ports for translation. Rotation can be done with the cockpit reaction wheel.

Some Angle of Incidence will also help, once the above has been solved.

And you definitely need more fuel, if you plan to return from Duna without refueling.

1 hour ago, jsisidore said:

Your take off was far more quicker than mine, are your specs are still the same? I want to compare.

Just download it again. The updated version is here.

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You don't need the help of nukes to break sound barrier and you reach mach 3 while below 10km, I didn't know that!

Yup. That's the power of low drag.

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You still have heaps of fuel left and I bet you can go to Duna with that.

Yes, getting to Duna orbit should be very possible, and returning to Kerbin, likely, too, without refueling.

Landing, while technically possible, will be very hard with those small wings, and returning impossible withour refueiling.

Even this 66 t beast isn't able to do that.

https://kerbalx.com/crafts/9756

[mk1980]

i did a roundtrip to duna surface and back for some forum challenge a while back. it's not an easy task. you need A LOT of fuel to pull that off without mining equipment to make fuel in situ.

that plane wasn't pretty. it was basically a lot of fuel tanks with some engines at the back and a passenger cabin at the front. from experience, you'll need something like 3500 m/s in kerbin orbit to get to the surface of duna and back. my plane had a bit more and had like 200 m/s left after aerobraking into kerbin orbit -which i spent on a plane change to try and line up with the equator for a KSC landing (didn't work, that beast was uncontrollable with empty tanks)

i basically had to "cheat" with the landing on duna (there are parachutes stowed in the service bays on the inner tank stack). getting back to orbit was painful with just 2 nukes. not going to do that again ever.

bottom line is - it's a lot of effort to squeeze in enough fuel for the transfers and the return from duna surface to orbit. and it's quite a hassle to get a plane with so much excess fuel to kerbin orbit in the first place.

[jsisidore]

1 hour ago, Val said:

1. Excessive RCS blocks. On sub-50 t crafts, you only need 6 ports for translation. Rotation can be done with the cockpit reaction wheel.

2. Some Angle of Incidence will also help, once the above has been solved.

3. And you definitely need more fuel, if you plan to return from Duna without refueling.

https://kerbalx.com/crafts/9756

1. What are ports of tranlsations?

2. What is Angle of Incidence? You mean wings?

3. Is there a ratio of fuel to weight?

[jsisidore]

4 minutes ago, mk1980 said:

i did a roundtrip to duna surface and back for some forum challenge a while back. it's not an easy task. you need A LOT of fuel to pull that off without mining equipment to make fuel in situ.

that plane wasn't pretty. it was basically a lot of fuel tanks with some engines at the back and a passenger cabin at the front. from experience, you'll need something like 3500 m/s in kerbin orbit to get to the surface of duna and back. my plane had a bit more and had like 200 m/s left after aerobraking into kerbin orbit -which i spent on a plane change to try and line up with the equator for a KSC landing (didn't work, that beast was uncontrollable with empty tanks)

i basically had to "cheat" with the landing on duna (there are parachutes stowed in the service bays on the inner tank stack). getting back to orbit was painful with just 2 nukes. not going to do that again ever.

bottom line is - it's a lot of effort to squeeze in enough fuel for the transfers and the return from duna surface to orbit. and it's quite a hassle to get a plane with so much excess fuel to kerbin orbit in the first place.

I see. You landed on Duna with parachutes? I wouldn't call that cheating if it is more efficient. What if you take your design and just "cut it in half"? Two rapiers and one nuke? If basically you are saying that the mass was a challenge in itself? Will the laws of game physics allow for it to work?

[mk1980]

yeah i suppose it might be possible to to a half size version of the same thing. but that plane had almost no payload to begin with (really just the passenger cabin for 4 kerbals, not even a cargo bay with science instruments or similar). and some of the elements in the design are sort of "fixed" weight - you'll need at least 3 landing gears and i don't trust in the small ones, so the "half size" plane would have to carry the same weight of landing gears. don't know if that would break the design completely. won't make things easier, though. 

instead of the 4 person cabin, i could use the mk1 cabin for 2 passengers, or an inline cockpit (which is about the same weight). those items have terrible heat resistance, though. reentry from an interplanetary transfer is no joke. an it's not fun to fly all the way to duna and back just to blow up when you finally get home

i don't consider that type of spaceplane very practical, tbh. i only made it for the challenge, but if i were to use something like that in a career game, i think i'd cut the fuel down dramatically and just pack a mining drill and small converter. or more likely - i'd just send up another plane and refuel the expedition plane in kerbin orbit before i send it off.

 

[Val]

23 minutes ago, jsisidore said:

1. What are ports of tranlsations?

Translation is movement without Rotation.

 

And you need at least one RCS thruster (port) pointing in each of the 6 directions.

 The 4-port thruster is bad for spaceplanes because of low temperature tolerance.

The single port thrusters has great temperature tolerance.

 

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2. What is Angle of Incidence? You mean wings?

Angle of Incidence is the term for when the wings are mounted to the fuselage in such a way that they have Angle of Attack, even when the fuselage and rest of the craft does not.

The reason why this is a good thing is explained in Angle of Incidence section of my article. (I linked it earlier, too)

 

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3. Is there a ratio of fuel to weight?

Probably. But it's too much hassle to calculate, because it depends on engine types and payload, so I just trial and error it.

[jsisidore]

20 minutes ago, Val said:

Probably. But it's too much hassle to calculate, because it depends on engine types and payload, so I just trial and error it.

Thanks. That's how I'm doing it, with a trial and error approach, it's fun but tedious. I will stay with the original engine combo and I'm thinking instead of a rover to put a drilling setup, this way the whole operation would be less stressful...

Edited June 10, 2016 by jsisidore

[jsisidore]

Val, talking about "fuel lines", I assume you have two way cross feed between your main and side tanks?

[mk1980]

you don't need fuel lines for the rapier engines - they pull fuel from all tanks equally even when you switch them to closed cycle mode. the nukes pull fuel like standard rocket engines (most distant tank first, drain empty, then move to the next). fuel lines add drag and nukes burn slowly, so it may be more efficient to just transfer liquid fuel manually to the tank that is directly attached to the nuke.

unless you are lazy (like me  )- in that case you'll want at least some fuel lines that feed into the tanks of the nukes. they do add drag, so it's not smart to use them on a plane if you can avoid it.

[AeroGav]

6 hours ago, jsisidore said:

..

3. Is there a ratio of fuel to weight?

First of all, Kerbal engineer shows a lot of useful stuff but don't trust it's delta V info especially relating to spaceplanes.   Rocket engines, and this includes the NERV, can only take fuel from tanks in the same fuselage stack as themselves, unless you use manual fuel transfers.  Therefore kerbal engineer will not take account of fuel in the rapier engine pods when calculating your delta V.

Second,  going to Duna and back single stage is very hard.   I have only just recently done it, and the margins are thin.   It would be nicer to enjoy the trip and land on a few different sites, do a bit of sightseeing, not sweat every inch of the way.  Actually I told you about this ship in my first post in this thread -

https://kerbalx.com/AeroGav/Astrojet-Lancer

Touchdown over 70m/s results in a crash landing most  of the time, so quicksave a few hundred metres above the surface.  Really I would not attempt to land there unless your spaceplane can land at under 40m/s on Kerbin.  On Duna stalling speeds are higher due to thin atmosphere.

The above plane has two service bays which i rotated to face downwards and each one has a downward facing pair of vernier thrusters in it, which i use the RCS controls to thrust upward and lower my landing speed a bit more.   My 30 ton Astrojet Citation has 3 verniers mounted in the belly and landed at 50 m/s.

Next point - Rover.

I've never launched one from a spaceplane,  i think it would be really cool, but honestly, why ?  You have an airplane.  With wings. Wheels,  and engines.  You can visit every biome on Duna by flying to it or just drive over the surface like a rover.

 

Now back to the overall mission concept.

Like I say, single stage to duna is very hard.   Consider making the pods on the sides with the Rapiers jettisonable.   Use fuel ducts or manual transfers to suck all the fuel out of them first,  then when the rapiers flame out at 29km, jettison the Rapiers (2 tons each), the empty tanks, the intakes and the drag associated with all that.    This is the least labour intensive way to make a comfortable round trip to Duna.   No refuelling, no docking or rendez vous,  just takeoff,  and aim for the little red dot.

https://kerbalx.com/AeroGav/Astrojet-Citation-X

2 underwing panther pods/fuel tanks, 1 rapier at the back,  2 nervs either side of the rapier have jettisonable covers for reduced drag.

after jettisoning all that stuff, reach orbit with nearly 4000 delta V.   Duna and back with ease, visit every biome too.

 

Alternatively,  you could refuel your space plane in low kerbin orbit before setting off for Duna, with a rocket or another spaceplane.  This is a lot of work however because i means a rendezvous and docking maneuver.

I've done it with Insitu Resource Utilization too,  but i had to stop at minmus to mine fuel, did not try to go direct to duna.  In fact, even though this plane shed 2 panther boosters and only had the small ISRU converter and a single small drill, no payload beyond the cockpit, it only reached minmus from Kerbin with 400 dv left.

Of course, having finally reached Duna with an ISRU spaceplane, you  might just want to keep going.  I just kept planet hopping outwards to Eeloo before coming home.   Mission time 40 years.  Hope my Kerbonauts brought a good book.

 

Optimising your design -

Put the solar panels inside the cargo bay.  I never use RCS thrusters on a spaceplane, because drag is always more important than weight.   Reaction wheels instead.

Eliminate struts and fuel lines, each one is like a 5% drag penalty.

Try attaching nose cones to the back of your engines, then use the offset tool to slide them forwards so they can no longer be seen, which means the game will no longer realise the nozzle is blocked and give you the benefit of the reduced drag while still being able to use the engine.  Nozzles are a major source of drag.   This is gamey but what you are attempting is very hard and i think it's justifiable.

 

Fuel Fraction -

I already covered this in a previous answer.  A rocket can be up to 80% fuel in weight, but a spaceplane has a lower fraction, a NERV spaceplane with heavy, but efficient engines lower still.   50% fuel fraction is actually the upper end of the scale, it might be hard to fly with that much.   40% more typical.

 

Wings -

You can tile the big S wings like the modular ones if you are a little creative with the rotate and offset tool.   Can be ugly if you get too close to it, but looks ok from most angles -

Try to avoid attaching wings to other wings to minimise flexing.    The 3 inner wing sections all attach direct to the main fuselage. the outer one attaches to the mid wing.  

The advantage of big S spaceplane wings is that each one holds 300 fuel.   Also consider swapping the plain nosecones for NCS adapters which also hold 80 fuel each - it all helps.

Edited June 10, 2016 by AeroGav

[jsisidore]

This new info raises questions.

But first my plan, and it is quite simple:
I will not refuel in orbit, I was thinking about but it is just too cumbersome. Thus I will not need RCS since I do not intend to dock.
I will refuel on Duna(or Minmus, really no clue at this stage) with a small mining setup which I will fit into a small cargo container. This will give me the right ballance entering Kerbin atmosphere.
I'm definetly looking at those big S wings, since I want to angle them, I already installed a mod for this job, but when it comes to wings I tend to procrastinate.

I don't want to jetisson anything because I think I might need it, but this raises a question:

1. can you land a ship with nukes with no problem on Duna and then on Kerbin?

2. Another question: fuel crossfeed. If rapiers ignore inteconnection between tanks and drain fuel eqaully(weird), that means they will never run out before nukes, but if nukes will I will have tanks full of fuel and no way for them to get to that fuel.

3. How would one transfer fuel manually without a fuel line?

[mk1980]

27 minutes ago, jsisidore said:

This new info raises questions.

But first my plan, and it is quite simple:
I will not refuel in orbit, I was thinking about but it is just too cumbersome. Thus I will not need RCS since I do not intend to dock.
I will refuel on Duna(or Minmus, really no clue at this stage) with a small mining setup which I will fit into a small cargo container. This will give me the right ballance entering Kerbin atmosphere.
I'm definetly looking at those big S wings, since I want to angle them, I already installed a mod for this job, but when it comes to wings I tend to procrastinate.

I don't want to jetisson anything because I think I might need it, but this raises a question:

1. can you land a ship with nukes with no problem on Duna and then on Kerbin?

2. Another question: fuel crossfeed. If rapiers ignore inteconnection between tanks and drain fuel eqaully(weird), that means they will never run out before nukes, but if nukes will I will have tanks full of fuel and no way for them to get to that fuel.

3. How would one transfer fuel manually without a fuel line?

1. what dou you mean exactly by "land with no problem"? i don't think i noticed any problems with the nukes. when you make "traditional" (non-plane) spaceships with nukes and reenter retrograde, nukes can blow up, but on a plane that's very unlikely. usually the stuff at the nose gets hot first. you'd probably blow up the node of the plane before the nukes even display a heat bar. if that's not what you mean, please clarify

2. the rapiers will need both oxidiser andliquid fuel to work, so the moment you run out of oxidiser, they stop working (in "closed cycle mode"/"rocket mode"). that's not a bad thing. if you have multiple fuel types on a ship, you generally want to burn the least efficient fuel first to maximize the deltaV you can get out of the ship

3. on a windows PC, you hold down the alt key ( i think mac and linux sysems have different "modifier" keys) and click (or was it right click?) 2 (or more) tanks. then the game shows "in" and "out" labels on the contect menu of the tanks and you can transfer fuel from one tank to another.

the system works best when you drain multiple tanks into one target tank (click the "in" button on the target tank) or refill multiple target tanks from one source (click the "out" button on the source tank). if you click the "out" button on multiple tanks, the logic gets confusing and the tanks will seemingly randomly push/pull fuel

also note- if you want to do that in career mode, the function requires a building upgrade (i think the R&D must be upgraded) - not relevant in this case i guess.

 

also a word of caution regarding mining: if you don't have a survey scanner in orbit that gives you an idea where the higher ore concentrations are, it is a bit of a gamble. you may end up with a poor location and it will take a long time to refuel. you should bring an engineer with a high level (level is the rirrelvant in sandbox/science mode-- all kerbals are level 5 by default). engineers speed up the mining dramatically (i think a level 5 engineer speeds it up by a factor of *20 or something). and you need neough power and cooling for the drill(s) and converter to work properly. also, you must have at least one small ore tank (the converter can only convert ore to fuel and the ore must be "buffered" in an ore tank - can't directly convert freshly mined ore to fuel without an ore tank)

 

[jsisidore]

2 hours ago, mk1980 said:

also a word of caution regarding mining: if you don't have a survey scanner in orbit that gives you an idea where the higher ore concentrations are, it is a bit of a gamble. you may end up with a poor location and it will take a long time to refuel. you should bring an engineer with a high level (level is the rirrelvant in sandbox/science mode-- all kerbals are level 5 by default). engineers speed up the mining dramatically (i think a level 5 engineer speeds it up by a factor of *20 or something). and you need neough power and cooling for the drill(s) and converter to work properly. also, you must have at least one small ore tank (the converter can only convert ore to fuel and the ore must be "buffered" in an ore tank - can't directly convert freshly mined ore to fuel without an ore tank)

 

Thanks for clearing that up. I did setup a mining base with 4 drills and a big converter on the Mun a couple of months ago, I remember it took many days to refuel, I can't imagine how long it will take it to refuel with a small setup, really no clue.

So I made it to kerbin orbit! With some fuel to spare. The new design had 36 tonnes and more fuel.

[Waxing_Kibbous]

Here is a fun video:

 

[AeroGav]

3 hours ago, jsisidore said:

I don't want to jetisson anything because I think I might need it, but this raises a question:

1. can you land a ship with nukes with no problem on Duna and then on Kerbin?

1.  Of course.   Duna has much less gravity than Kerbin and a thin atmosphere,  so takeoff under nuke power is very easy.   You can land back on Kerbin without any power at all, just gliding, you just need to  re-enter somewhere reasonably close to the space centre.    

Jettisoning the airbreathing engines as you pass through 29km on Kerbin can make things easier if you are struggling because you won't need them again - it's just 4 tons +  of dead weight  you are hauling to Duna and back.   I dont see a point in jettisoning anything else because you will need your mining equipment on Duna itself.   Once you have refuelled there, you could theoretically leave it behind, but there is no point because the return to Kerbin requires less delta v than the outbound journey.     In fact the hardest part of the trip is the initial step from Kerbin to Minmus.

I would just bring a single small drill and the small converter.    When you are mining,  you can go into time warp at 100,000x normal speed and the tanks refill just about instantly.   The only problem is, during the night time, you run out of electricity, the converter and drill stop and don't automatically restart when the sun comes up again.    It get's a bit tedious having to restart them every morning.

However, on Minmus, there is some kind of bug where solar panels continue to produce power even at night.     On Duna you might have to restart 20 times to get enough fuel to completely refill, or half that much to just have enough to go home again.  It might be easier to refuel on Duna's moon,  because apparently it is tidally locked and one side is permanently facing the sun and the other permanently at night.

PS  - orbital survey scanner - they don't weigh much but they are bulky, you can put it in small cargo bay but it will clip through other stuff.   

Gratz on orbit btw.

Edited June 11, 2016 by AeroGav

[mk1980]

i did a bit of testing regarding the ISRU. made a "quick and dirty" tourbus-style spaceplane with an mk3 passenger cabin in sandbox and just enough deltaV to get to minmus to refuel.

the cargo bay contains a small converter, a large drill (i'd always go for a large drill if you land "blindly" with no knowledge of ore deposits - the small one requires a minimum of 2.5% and if your landing spot has less, you're screwed). 1 big solar panel (might need more for outer planets- solar power output scales with proximity to the sun) and 1 small radiator. plus a big battery as buffer (would need more than 1 if it's supposed to cover the whole night). and a surface ore scanner (not really necessary if you're not going to drive/hop around in search for better spots)

the tanks were almost empty when i landed and it took about 50 "in game" days to fill up ~7000 LF and ~4500 Oxidiser. there are multiple engineers on the craft, but i honestly don't know if only the highest level counts or if multiple engineers stack. obviously, with more drills or the big ISRU, it could have been much faster, but chances are that you'll have to wait a few months or years for the launch window back home anyway if you fly to duna or further out/in, so it doesn't really matter that much if you need 5 days to fully refuel or 100.

the landing spot had a moderate ore concentration (4.5%)

if you rely on ISRU, it's probably a good idea to have a named save (ALT+F5) while still in orbit so you can redo the landing and pick another spot if you happen to land on a really terrible ore concentration.

 

Edited June 11, 2016 by mk1980

[jsisidore]

That is a massive ship. Well yes I don't "go" anywhere without saving first. I got a question regarding the lift, is it okay if you have can't lift your nose while taking off? Will I be able to lift off on Duna? I went further than 120m/s before reaching the end of the runway. Also what landing gear do you use? Crash tolerance wise will it make sense go for those that have 70m/s, I assume this is the max speed to land safely?

[mk1980]

it's more of a "brute force instead of efficiency" craft. the payload is basically the mk3 cabin (6.5 tons) and about 3 (?) tons worth of  mining equipment in the cargo bay. there are more elegant ways to get such a payload to minmus, but brute force also works

i tend to use the medium sized landing gears on mk2 planes and either the large or extra large (for heavy cargo) on mk3 planes. i think this plane actually uses the medium gear since it's *relatively* light for an mk3 SSTO (< 100 tons fully fuelled)

in my duna SSTO, i also used medium sized gear, but i didn't land it like a plane, so i guess that doesn't really count. 

regarding the pitching up: when in doubt, you can always put a few reaction wheels somehwere in the tank stacks or in a cargo bay. they don't have a lot of mass, make orbital maneuvers less tedious and help (a bit) with maintaining attitude during reentry. alternatively, you can put a few RCS ports or vernor engines (basically more powerful RCS ports that use LF/Ox instead of monopropellant) on the belly somewhere in the foreward half of the plane and toggle RCS for the takeoff (so they assist when you pitch up). guess that should be enough.

[jsisidore]

Alright, or all bad, the trip to Duna and getting into orbit was a piece of cake, but as soon as I began to actually land I realized it will never happen. Unless I learn how, are there any good tutorials on how to land an ssto on Duna? I found one video but the guy was using parachutes, for some reason I did not got one.

Also, the surface is ridiculously hilly.

Think I will put on some parachutes and bigger landing gear next time.

[Val]

3 hours ago, jsisidore said:

Alright, or all bad, the trip to Duna and getting into orbit was a piece of cake, but as soon as I began to actually land I realized it will never happen. Unless I learn how, are there any good tutorials on how to land an ssto on Duna? I found one video but the guy was using parachutes, for some reason I did not got one.

Also, the surface is ridiculously hilly.

Think I will put on some parachutes and bigger landing gear next time.

Yeah, it's really hard to land a plane on Duna. Took me several hours of Quick Loads before I pulled this one of.

 

Using parachutes or VTOL engines can help though. This one I nailed in first try.

 

[AeroGav]

4 hours ago, jsisidore said:

Alright, or all bad, the trip to Duna and getting into orbit was a piece of cake, but as soon as I began to actually land I realized it will never happen. Unless I learn how, are there any good tutorials on how to land an ssto on Duna? I found one video but the guy was using parachutes, for some reason I did not got one.

 

Also, the surface is ridiculously hilly.

Think I will put on some parachutes and bigger landing gear next time.

This is why I said you need to get your landing speed below 70 m/s, preferably 50 or 40.

My 20 Ton ship i linked in this video , 

Has two pairs of Big S delta wings and one pair of Big S strakes (lift rating 22 total) = 40 m/s stalling speed on wing lift alone.

With 4 Vernier lift engines in the service bays I can bring that down to 25 m/s.  I was trying to see how slow I could land,  but it would have been better to add a little more speed and not be pitched up at such an extreme angle on touchdown since plane tumbles forward so hard when the rear wheels hit.

 

I suspect your 35 ton craft needs more wings Jsisidore.

 

I built a craft very similar to yours Jsi  in 1.0.5,  and it took me about 15 attempts to get down in one piece.   The problem is due to the very uneven terrain - one wheel hits first and causes the plane to start flipping or tumbling.   The nose, tail or wingtip dig in to the ground and your plane starts desintegrating.

The only real fix for this is to get the landing speed down.

What may help a little 

1.  from orbit, you can see a dark trench running east to west across about 1/4 of Duna's diameter,  slightly north of the equator.   This is a lowland and is slightly flatter than the rest, though not by much.  More importantly it is at low altitude, which means thicker air on touchdown = more lift = slower landing speed.

2. widely spaced gear helps to make it less prone to tumbling.  Attach to the wings near the tips, not to the fuselage, but remember to use angle snap tool to make sure they are straight.   I used medium gear.     I have not tried it, but perhaps a 4 landing gear "car" style layout would be better than the usual tricycle.    

 I also landed a taildragger successfully.

3. LAnd with SAS on.   If uneven wheel contact jolts the plane off prograde, the SAS will react faster than you can to start trying to correct the deviation.

Here is a video of my Astrojet Citation landing on Duna at 50 m/s.  A bit rough but somehow the wings didn't break...

 

EDIT -  I would like to emphasise that all 3 of the craft pictured above landed on Duna successfully first time, on account of their low landing speed and widely spaced gear,  where the one coming in at 100 m/s crashed 14 tries out of 15.

Edited June 11, 2016 by AeroGav

[jsisidore]

Great videos guys. Yes AG, I remember you said I need more wings to land on Duna, but the stock parts force you to create really abstract shapes, I wish for a better wing builder where you could design your own wings, in fact it is quite silly that there is none.

Val, what is that orange arrow marker in your video, it seems useful.

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I have not tried it, but perhaps a 4 landing gear "car" style layout would be better than the usual tricycle.

Seems logical.

[AeroGav]

You could try out B9 Aerospace's procedural wings mod.   Create wings with any span, thickness and sweep angle you want.

[Foxster]

Just for fun, here's another variation...

You can just squeeze a nuke in here on the back of a surface-mounted nosecone. Keeps the whole craft low-drag by having just the one fuselage. 

And here's a way to get an intake and a capsule at the front...