The Most Efficient Spacecraft Designs That Can Go Further More

[Kerbal Nerd123]

Today I realized that i didn't explore other planets at all I only explored mun and the other moon. SO I was like let's go exploring in KSP in that time realized i need some sort of a good and efficient spacecraft.So in this topic we will just talk about what's the best spacecraft to build for landing on other planets and coming back safely.My Targets are to land on Duna,Eve Or Jool. I haven't yet build a good craft to go somewhere 

[Wjolcz]

A lander.

[Sharpy]

46 minutes ago, Veeltch said:

A lander.

One?

A good method to cover several biomes of Eve is to send a bunch of microlanders

[juanml82]

The easiest way is to do it Apollo style: an interplanetary tug carrying a lander.

A good medium sized tug is a 2.5m stack with a probe core, reaction wheel, RCS and electricity. Fuel works with an orange jumbo tank (use interstellar fuel switch to turn it into a liquid fuel only tank) with either four radially attached Nervs (radially attach an MK1 liquid fuel tank, the nervs attach to the bottom of it, remember to use fuel lines to pass fuel from the central tank) or a mod's 2.5m Nerv alternative (MRS has a good one). You can throw in a mobile science lab to it, Make sure you add docking ports.

You Mun lander should serve as the basis for your planetary landers for Duna and most of Jool moons. If you're using Terrier engines, you might want to replace them for aerospikes for Duna and maybe for Vall, depending on your lander's weight.

In Duna parachutes (specially drogue) will help you slow down but they won't slow you down enough, so you'll have to make a powered landing anyway - parachutes save you fuel. Duna has an atmosphere but doesn't have oxygen, so airbreathers don't work. While you can fly a plane (with aerospikes, terriers or some mod engine which works in any atmosphere) you need to design it differently than a Kerbin's plane. There is a tutorial about flying with wings in Duna somewhere. Keep in mind it is a challenge. Dropping on vertical rockets is a lot easier.

Laythe has an oxygenated atmosphere, so you can may want to carry a spaceplane there. Basically, if it can go from the KSC all the way to LKO, it will easily work in Laythe. But Laythe is mostly water and the terrain is rather rolling, so horizontal landings can be tricky. OTOH, you can land in the water with the proper design. Or just use a vertical rocket. Parachutes will slow you down enough to land.

Tylo requires a lot of dV and thrust to land (something like 3,500 m/s for the whole down and up again trip). While nervs will give you a lot of dV (and double as interplanetary engines), they may not allow you to kill your horizontal speed before crashing into the terrain. Personally, I use a 3.75m stack with a Rhino to kill horizontal velocity and most of the vertical velocity to land there, and stage it before I actually land.

Eve is KSP's final boss. I haven't yet check which kind of design work with all the changes in heat and drag since 1.0.5

[Magzimum]

Follow the following steps:

1. Build a lander - these are usually specific for the Planet / Moon you're trying to visit. They differ in:
   1. Amount of fuel to land and take off again
   2. Parachutes (often not functional, sometimes essential)
   3. Your design choices, such as the number of Kerbals and science instruments
2. Build a launcher
   1. Add Moar Boosters until it is capable of going there and back again.

Most important: just try. You will fail several times, and if you don't start trying, you won't get there.

[Foxster]

If you haven't already then I'd strongly recommend an information mod like KER or MJ. Its really hard to plan a longer trip without knowing things like dV and TWR. 

Also have a search back through Spacecraft Exchange on this forum. There are some pretty amazing designs there for going just anywhere and doing anything. 

[Aegolius13]

Nukes are advisable for most interplanetary destinations, unless your skip is very small.  Though it's less of a big deal for trips to Duna, which is not much more delta intensive than the Mun. 

[KerikBalm]

4 hours ago, Kerbal Nerd123 said:

... for landing on other planets and coming back safely. My Targets are to land on Duna,Eve Or Jool. ...

Good luck with that....

Just kidding, I'm pretty sure that you mean one of its moons.

Anyway, for interplanetary missions, you'll definitely want a lander that separates from the main craft.design each lander for the destination, and the interplanetary stage(s) according to the mass of your lander.

Hint: an Eve lander will be much more massive than a Duna lander

[Chiron0224]

8 hours ago, Foxster said:

If you haven't already then I'd strongly recommend an information mod like KER or MJ. Its really hard to plan a longer trip without knowing things like dV and TWR.

I concur, now if they would only UPDATE THEM FOR 1.2!!!  Seriously though I know not to poke the bears, they are working as hard as they can.  I am getting anxious though because I've just gotten to that point in my current career save where my eyes turn to Duna and the other planets.

[IWanttobeEVA]

For Duna and Eve chemical rockets work just fine. I prefer the mothership+lander approach. Build it with a little more dV than you would to go to Mun and it will be pretty close. You can test it by going the Mun and back to see who much extra dV you have.

Mission to Duna before leaving Kerbin:

 

 

Edited November 19, 2016 by IWanttobeEVA

[StrandedonEarth]

9 hours ago, KerikBalm said:

Hint: an Eve lander will be much more massive than a Duna lander

An Eve lander can be smaller than a Duna lander because you don't need to do a powered landing in Eve's thick atmosphere; 'chutes work just fine. An Eve ascent vehicle, on the other hand....

Edited November 19, 2016 by StrandedonEarth

[Foxster]

37 minutes ago, Chiron0224 said:

I concur, now if they would only UPDATE THEM FOR 1.2!!!  

Err, MJ was updated for 1.2 quite a while ago. Or at least the dev version was, which is really solid. 

[KerikBalm]

8 hours ago, StrandedonEarth said:

An Eve lander can be smaller than a Duna lander because you don't need to do a powered landing in Eve's thick atmosphere; 'chutes work just fine. An Eve ascent vehicle, on the other hand....

Well... a "lander" is not a technical term... so far the only spacecraft called a "lander" was meant to land and return. I was also replying to a question explicitly about landing and returning

Bust even for a descent vehicle, I'm not sure that's right. I often need to do powered landings on Eve because of the strong gravity (but then again I'm also landing much larger craft, since there is an intent to return).

Even excluding powered landing on eve, Eve descent also has leads to much more heating, and thus you need to use more mass on thermal protection.

Dunas atmo isnt that thin, you can do unpowered descents as well. They may be worth it if you dont intend to return, and thus the engine mass doesnt do double duty (so that the added mass is just a tiny bit of fuel vs a multiple parachutes)

 

[Kerbal Nerd123]

Holy Crap Too much stuff

[septemberWaves]

On 11/18/2016 at 11:38 AM, Kerbal Nerd123 said:

My Targets are to land on Duna,Eve Or Jool.

If you want to land on Jool itself you're going to be very disappointed.

In any case though, the best way to make a vehicle for a particular location depends on the location. You do need to be good at docking though - whilst a Direct Ascent profile (single launch, single vehicle that lands everywhere, no docking required) is doable for Duna, it's far more difficult than other methods, and in any case Direct Ascent doesn't work well for Eve or for Jool's moons. It can be done, but it's easier to just learn how to dock spacecraft. Also, if you have a way of calculating delta-v, this map can be very helpful (there's also a version to include the Outer Planets mod if you ever use that).

Duna

Duna's easy to do with a Duna Orbit Rendezvous (Apollo-style) profile, wherein you have a single launch from Kerbin that has two payloads: the Duna lander and the Kerbin return vehicle. Duna's not difficult to make a single stage lander for, but for someone who's less experienced it might be best to try a 2-stage lander consisting of a descent module and an ascent module. Landing on Duna and returning to orbit (assuming you use parachutes and an engine to land) takes about as much delta-v as going from low Kerbin orbit to the surface of the Mun and then back to an aerobraking trajectory with Kerbin. The Kerbin return vehicle is even simpler, since it only takes around 600m/s of delta-v to escape Duna's SOI, which means a rather small fuel tank (for comparison, an ascent from the surface of the Mun takes a similar amount of delta-v). If you also want to land on Ike, it's usually easiest to add a bit of extra fuel in the ascent stage of your Duna lander, and use that for the Ike landing.

Jool system

In terms of difficulty (assuming you want to return your kerbals to Kerbin), the next level is the Jool system. In order of difficulty for landing and returning, the moons follow this order: Pol, Bop, Vall, Laythe, Tylo. You can't land on Jool itself because it is a gas giant and thus has no surface, but you could potentially drop a probe into its atmosphere to transmit some science data.

For the Jool system, you'll probably want to construct an interplanetary transport in a separate launch from your landing vehicles. The transport will need nuclear engines (which run on liquid fuel with no oxidizer) because the Jool system takes a lot of delta-v to get to. You'll also need to learn how to use the Joolian moons (mainly Laythe and Tylo) for gravity braking, as this can cut down enormously on the amount of delta-v you need to get into orbit of Jool. Also, you'll need to consider which moons to visit; unless you're doing a Jool 5 mission, it's generally best to do Pol, Bop, and Vall with the same mission, and have a single dedicated mission for each of Laythe and Tylo.

For the landers, Pol and Bop are very easy to land on and have such low gravity that even an ion engine can land a reasonably-sized payload on them, so there's no point using a multi-stage lander. Vall can be done using slightly less delta-v than the average Duna lander, and it's also not difficult to make a single-stage lander for Vall.

Laythe gets rather challenging. It takes almost 3000m/s to ascend from Laythe (for comparison, a Kerbin ascent takes around 3500m/s for the average pilot), which generally means a rather large lander is needed. The good news is that you can land using parachutes instead of fuel - but be careful, because Laythe is mostly ocean and has very few islands large enough to land on easily. Laythe missions can be done most easily using a spaceplane as Laythe's atmosphere has oxygen, but since you appear to be rather new to the game I imagine spaceplanes may be somewhat beyond your current abilities. Still though, give it a try if you want to - no one learns anything in this game without attempting it themselves.

Tylo is the ultimatum for non-atmospheric landing vehicles. It's nearly the size of Kerbin but has no atmosphere to slow you down. Theoretically it takes only 4500m/s to land on Tylo and return to its orbit, but I've found that it's safest to go with at least 5200m/s. In case you don't use a mod that lets you calculate delta-v, this is similar to the delta-v needed to get from the surface of Kerbin all the way to Mun orbit. Single-stage Tylo landers are plausible, but ugly, and also enormous and thus enormously difficult to transport to Tylo. Your best bet is to use the tiny rover seat instead of a crew pod, and minimize your lander mass as much as possible. Also, you probably should cheat your landers to Tylo beforehand (in a test save if you don't want to cheat in your career) just to test them out and ensure that they work. The last thing you want is to crash into the surface of Tylo after spending a huge amount of time and effort designing the necessary spacecraft and flying them to the Jool system. Another thing which might be a good idea - particularly with a very massive Tylo lander - is to send your Tylo lander separately from your crew vehicle, and rendezvous them in Tylo orbit.

Eve

Eve is the single most difficult planet to land on and return from (in the stock solar system at least). The planet takes the least amount of delta-v to get to, which is convenient because Eve ascent vehicles are absolutely gargantuan. The amount of delta-v needed to ascend from Eve is more than double what it takes to ascend from Kerbin - and you have to land a rocket capable of doing that on the surface of Eve in the first place. You also need to use engines that actually work in Eve's thick atmosphere, which really means that your only options for the lower stages are aerospikes or Vector engines. You'll also want to use asparagus staging. Basically, Eve landers are enormously difficult to engineer compared to anything else in the game, and it's probably best to find a more in-depth explanation of how to reach Eve orbit from the surface of Eve - or just try it out yourself by cheating various vehicles to the surface of Eve and finding out exactly what doesn't work.

 

And one more thing: if you're going anywhere with gravity much higher than that of Moho, don't forget ladders.

[Thrawn889]

I have a pretty basic duna lander on its way to Duna not sure if i have any images of it but its a variation of my Mun lander with an engineer to reset my Parachutes before i leave. I might get them stuck tho,

 

I use KER. If you do a Forum search there is a 1.2 compatible release of it. Just not on Curse as it s main modder is Awol so its being updated by others.

[StrandedonEarth]

5 hours ago, KerikBalm said:

Well... a "lander" is not a technical term... so far the only spacecraft called a "lander" was meant to land and return. I was also replying to a question explicitly about landing and returning

I was mainly being a smartS 

[IncongruousGoat]

If you're considering ion engines, remember that solar power generation follows an inverse-squared law, meaning that any ion spacecraft in the outer solar system will be limited by their battery capacity-there's just no way to pack enough solar panels to provide continuous burn. They are good for low-mass Moho missions, though. If you're patient.

Also, for Laythe (and Eve too, I suppose, if you want to go down that route), remember-your lander has to be aerodynamically stable. You can't build the typical low-profile low-CoM lander; it needs to look more like a launch vehicle. Which doesn't make the already difficult task of landing on Laythe any easier.

Also, with all this talk of mods for calculating delta-V, let's not forget to mention how to do it by hand:

The Tsiolkovsky Rocket Equation:

Where Ve is exhaust velocity (equal to specific impulse multiplied by 9.81 m/s^2). m0 is the wet mass (the vessel mass when full of fuel) and mf is the dry mass (the vessel mass when empty of fuel).

[KerikBalm]

18 hours ago, eloquentJane said:

The transport will need nuclear engines (which run on liquid fuel with no oxidizer) because the Jool system takes a lot of delta-v to get to. You'll also need to learn how to use the Joolian moons (mainly Laythe and Tylo) for gravity braking, as this can cut down enormously on the amount of delta-v you need to get into orbit of Jool. Also, you'll need to consider which moons to visit; unless you're doing a Jool 5 mission, it's generally best to do Pol, Bop, and Vall with the same mission, and have a single dedicated mission for each of Laythe and Tylo.

...

Laythe gets rather challenging. It takes almost 3000m/s to ascend from Laythe (for comparison, a Kerbin ascent takes around 3500m/s for the average pilot), which generally means a rather large lander is needed. The good news is that you can land using parachutes instead of fuel - but be careful, because Laythe is mostly ocean and has very few islands large enough to land on easily. Laythe missions can be done most easily using a spaceplane as Laythe's atmosphere has oxygen, but since you appear to be rather new to the game I imagine spaceplanes may be somewhat beyond your current abilities. Still though, give it a try if you want to - no one learns anything in this game without attempting it themselves.

Tylo is the ultimatum for non-atmospheric landing vehicles. It's nearly the size of Kerbin but has no atmosphere to slow you down. Theoretically it takes only 4500m/s to land on Tylo and return to its orbit, but I've found that it's safest to go with at least 5200m/s. In case you don't use a mod that lets you calculate delta-v, this is similar to the delta-v needed to get from the surface of Kerbin all the way to Mun orbit. Single-stage Tylo landers are plausible, but ugly, and also enormous and thus enormously difficult to transport to Tylo.

...

Eve

Eve is the single most difficult planet to land on and return from (in the stock solar system at least). The planet takes the least amount of delta-v to get to, which is convenient because Eve ascent vehicles are absolutely gargantuan. The amount of delta-v needed to ascend from Eve is more than double what it takes to ascend from Kerbin - and you have to land a rocket capable of doing that on the surface of Eve in the first place. You also need to use engines that actually work in Eve's thick atmosphere, which really means that your only options for the lower stages are aerospikes or Vector engines. You'll also want to use asparagus staging. Basically, Eve landers are enormously difficult to engineer compared to anything else in the game, and it's probably best to find a more in-depth explanation of how to reach Eve orbit from the surface of Eve - or just try it out yourself by cheating various vehicles to the surface of Eve and finding out exactly what doesn't work.

Re: Jool - you don't need Nukes. You just need to stage. dV requirements for the stock kerbal system are approximately 1/3 of real life dV requirements, but real life spacecraft don't outperform KSP rockets by nearly that much. I've made plenty of missions to go to Jool that use chemical engines. Even fully reusable ones. One ejection stage to take the craft from LKO to an escape trajectory, and then the next stage needs only 1000 m/s to get to jool. THe first stage can then aerobrake down to LKO for refeuling. Returning is also harder of course, but you can get one heck on an oberth effect from Jool, not to mention gravity assists.

But yes, Nukes make it a lot easier to do.

Re- Laythe - Most things float, so you can just design for a water landing. There wont be a flat planting, but your kerbal can still have a swim and take samples. Also note that orbital velocity is about 500m/s less than on kerbin, which makes SSTOing much much easier because the amount of dV you need from rockets after your jets stop working is much less (roughly half what you need on kerbin). Also its atmosphere profile is different, so jets will keep working at a higher altitude than on kerbin. Also note that jet TWR on the surface of laythe is less than on kerbin due to laythe's atmosphere being 0.6 atmosphers while its gravity is 0.8 Gs

Re: Tylo - the single stage landers aren't all that big.

My smallest lander with an enclosed cabin and full science package was <24 tons and 25 parts. Foxster got it done in about 15 tons.

Of course, this requires efficient designs, and good piloting because the margins are thin.

 

Re: Eve- dont forget mammoth engines. Also don't forget that its a lot easier if you land at a high elevation. You can land at a place that is 7km. Someone manages a SSTO from that 7km mountain.

 

[ShadowZone]

I myself am a big advocate of the "big cruiser, small lander" style of interplanetary exploration vehicles.

I once explored the entire Outer Planets Mod planets and their moons with one vehicle. The main ship was capable of landing on the smaller moons (Ovok, Priax, Tal, ...) while the lander was used to get on and off the "harder" moons (for instance Slate, Eeloo, Wal, ...).
While on those smaller moons, the main ship used its ISRU to replenish its fuel. So I always had enough power to get to the next celestial body.

Turns out it made for a nice video series
https://www.youtube.com/watch?v=_bBo1wiwaqo&index=3&list=PLLGqKphkhc2D3VG9NN6inD5xEeQ1itMyN

 

[Sharpy]

A note about Duna.

Lander mission alone is boring.

Make a good rover. Capable of crossing a good piece of Duna. Say, something that can travel between Northern Shelf and Northern Basin, through Midland Sea and two canyons. You'll cover at least 8 biomes. And the trip will be memorable.

Of course hauling all that ascent equipment around Duna is pointless, so build an ascent vehicle. In my experience, LV-N is perfectly capable of lift-off from Duna surface and a trip all the way back to Kerbin, so a two-craft mission (rover and return vehicle) is perfectly sufficient. Although having an orbital base is nice too.

[Terwin]

I generally go with rather large Mk3 based vessels so that I can store the ISRU in a cargo bay.

For the mun, I generally need 3 nuke engines, then I add a few empty fuel tanks/ore cans, slap on a couple extra nukes and head to Duna.

If you get low on fuel on your way to Jool/Duna, land on a low-g body first to refuel(Pol/Bop for Jool, Ike for Duna).

Several of my trips to Moho stop by Gilly(Eve) for a refuel.

For anything beyond a single-target scan-sat(to scan a given planet/moon for ore and biomes) I generally take ISRU along for the ride, if it weighs less than your return fuel, then it is more weight-efficient than hauling your fuel all that way. 

(I always bring ISRU because I am pretty good at having enough fuel to get there, but often do not have enough to get back without a refuel) 

[septemberWaves]

On 11/21/2016 at 1:04 PM, Sharpy said:

A note about Duna.

Lander mission alone is boring.

Not true! At least, not if you have that mod installed that brings back Duna's old appearance (Duna Restoration Project). And in any case, designing and flying a Duna mission can be very fun because it's easy, so there's a lot of room for interesting vessel modifications (for aesthetic or practical purposes). That being said, rovers are quite a fun payload.

[Majorjim!]

On 11/19/2016 at 4:02 PM, eloquentJane said:

Eve landers are enormously difficult to engineer compared to anything else in the game,

Nah.. No where near the hardest thing. It's just a case of TWR at launch and dv. It seems hard because there is no stock dv readout. An Eve ascent craft is a doddle to make. They are just suuper ugly and peeps find it hard to launch them from Kerbin for some reason.  I am in the process of thinking about one day maybe considering making a 'real life' looking Eve ascent rocket.

Edited November 22, 2016 by Majorjim!

[Jonfliesgoats]

On 11/18/2016 at 8:04 PM, Chiron0224 said:

I concur, now if they would only UPDATE THEM FOR 1.2!!!  Seriously though I know not to poke the bears, they are working as hard as they can.  I am getting anxious though because I've just gotten to that point in my current career save where my eyes turn to Duna and the other planets.

There is a decent DV calculator at strout.net and TWR is thrust/mass*local gravity.  On consoles I find I am much more calculator dependent, and it makes the game more fun.

Here's the strout.net link, if you don't feel like running the tsiolkovsky equation in your graphing calculator app:

http://www.strout.net/info/science/delta-v/