How to build up the nerve to go to Duna?

[Heartstrings]

So, I'm afraid I'm stuck. I don't know where to go, really. I'm rather new to the game, and I hit a roadblock something a week ago or so, and I'm having issues designing a rocket, heck, even a lander that could take me to Duna successfully. It's a combination of lack of motivation, overwhelmedness by the game's scope (and more specifically the massive distances involved between planets), a concern for safety for my kerbals, and having my first and second missions to the Mun (second time was to rescue the first, third time was to rescue the rescue mission) as well as my trip to Minmus being thiiis close to being a colossal failure because apparently I simultaneously overbuild and underbuild my rockets.

I need help. Can somebody find me a guide or something, or explain what I'm doing wrong, because I'm incredibly nervous and it's completely wrecking the game for me.

[Arron Rift]

If I'm not mistaken, you can use alt-F5 and alt-F9 to keep multiple quicksaves of your game. Every major mission I do I make a quicksave called "home" while the rocket is sitting on the Launchpad. Then make separate quicksaves once you are in orbit around Kerbin and while in orbit around the body you are landing on and once you've landed successfully...just make tons of quicksaves. That way if you get to Duna but slam straight into it, you can reload to back when you were in orbit and try again. If all else fails you can reload your "home" quicksave and have all your kerbals right back on Kerbin safe and sound like it never happened!

I do this, and to date I've never had to do a rescue mission

[Axelord FTW]

Practice,

monkey see, monkey do (watch videos of people doing it)

become apathetic toward kerbals...

P.S. post craft and we'll bicker about how better it could be.

EDIT: @Arron Rift.

That's scaredy-cat speak. Going and hoping for the best is best. Not to mention, much more thrilling!

Edited January 27, 2015 by Axelord FTW

[Heartstrings]

If I'm not mistaken, you can use alt-F5 and alt-F9 to keep multiple quicksaves of your game. Every major mission I do I make a quicksave called "home" while the rocket is sitting on the Launchpad. Then make separate quicksaves once you are in orbit around Kerbin and while in orbit around the body you are landing on and once you've landed successfully...just make tons of quicksaves. That way if you get to Duna but slam straight into it, you can reload to back when you were in orbit and try again. If all else fails you can reload your "home" quicksave and have all your kerbals right back on Kerbin safe and sound like it never happened!

I do this, and to date I've never had to do a rescue mission

Practice,

monkey see, monkey do (watch videos of people doing it)

become apathetic toward kerbals...

P.S. post craft and we'll bicker about how better it could be.

EDIT: @Arron Rift.

That's scaredy-cat speak. Going and hoping for the best is best. Not to mention, much more thrilling!

Apathetic towards kerbals? :U

But thanks for the Quicksave thing, I didn't know that. Time to murder kerbals but consistently set time back so they'll never know how much of a screwup I am!

Actually, this doesn't really help me with rocket building. I keep not adding enough fuel, or something, and if I add more then it just explodes on the pad, or the lower stages don't get built up enough, and by the time I quit I have a rocket capable of getting there but not back that takes up half or more of the VAB.

[OhioBob]

Why not try unmanned missions first to worked through all the problems before risking your kerbals?

[Heartstrings]

It's not that I'm concerned about the kerbals, it's that my rockets either don't get there, or are way too big and can't get back.

[Hannu]

Solution depends on your personal restrictions. People have very different sets of opinions and choices. You should tell what you do not want to do or use.

It is very difficult to make a Duna trip without planning. You have to know delta-v of many maneuvers, launch windows, basic orbital mechanics for dockings etc. One way to do it is to use suitable mods and tools. MechJeb is an excellent mod. It can show dvs of stages, calculate maneuver nodes, launch windows and even execute burns. In my opinion space flight game without such capabilities is a joke (or good modding platform). But seemingly other people find the long series of guesses without information and failed experiments as a fun and basic calculations and planning as a cheating or at least too nerdy stuff. Of course you can calculate everything by hand. Consult Wikipedia or textbook of celestial mechanics. Some basic knowledge from math is necessary. Alexmoon's porkchop plot calculator is an excellent tool to find out launch windows and dv requirements of interplanetary transforms.

Planning is best to start from lander. You can even test it if you use Hyperedit mod. Then you build a mother craft with enough dv for interplanetary burns (and life supplies, if you use such a mod). Then launcher to put everything on orbit around Kerbin.

You can also start unmanned and follow a real progress. First you can build a flyby probe. You learn to use porkchop plots to find launch windows and make interplanetary burns and trajectory corrections. Next step is an orbiter. You add a Duna orbit insertion burn. Then you can make a lander. Real planetary lander probes go typically straight to the atmosphere, but you should to do a low orbit first, because you learn for future. You find out what landing needs. After that the last step is an unmanned return probe. You need also Duna orbit rendezvous and return to Kerbin. After that you just build a larger manned ship and go on.

There are huge number of tutorial videos, if you want to use them. You can see what kind of stages is needed. But I decided that I make everything by myself and watch videos after that.

[Axelord FTW]

Actually, this doesn't really help me with rocket building. I keep not adding enough fuel, or something, and if I add more then it just explodes on the pad, or the lower stages don't get built up enough, and by the time I quit I have a rocket capable of getting there but not back that takes up half or more of the VAB.

This sounds like you are missing vital information.

Are you playing stock? Stock doesn't nearly provide enough information (well, it sorta does, but not readily) about how a rocket will behave and how far it can go.

How much delta-v does your ship still ahve once in low kerbin orbit (80km>70km AP&PE)? Do you know the delta-v budget needed to lift from Duna? How to you break your vessel (sections)?

Do you use any aerodynamic mod? Any part mods?

Also, what Hannu said.

[timsfitz]

Sounds like you need more practice building quality rockets. Maybe download someone else's and learn from them. Getting to Duna and back will be easy for you in a few months. Nuclear engines are your friends.

[Talavar]

To help with your fear, Get mechjeb, find "suicide burn" under custom window, add it to the "orbit info" window, keep it on your screen. Set periapsis to something like 10-15 KM. after entering the atmosphere, set SAS to retrograde and click on your hud and switch from orbit to surface. .. I suggest doing a quicksave before entering the atmoshere, and watching it crash into the ground once.. only watching how the Suicide burn works. It will fluctuate, but after watching it once you'll get a pretty good Idea of what's going on. Suicide burn calculates the last moment that you can save yourself by thrusting. if it goes under 0, you're dead. The atmosphere makes changes to this, so that's why I suggest watching ti first, then reloading and then actually trying to land. Also, use the Delta V window from mechjeb while building your ship. I Try to get atleast 12,000 DV total for vaccume (best to have extra just in-case something goes wrong). these two things are invaluable while Designing and landing manually. Good luck!

[OrtwinS]

1) Install Kerbal Engineer, it'll provide you with per stage dv information

2) Keep this map close by: http://www.kingtiger.co.uk/kingtiger/wordpress/wp-content/uploads/2014/02/KerbinDeltaVMap.png

just add up the numbers for your chosen location. From low Kerbin orbit to low Duna orbit you need about 1430 m/s dv for example. It is NOT exact, but it is a good indication (I suggest adding 50% extra dv, for reassurance)

3) Use something like Kerbal Alarm Clock or Protractor to figure out when to launch to Duna, I recommend KAC because it'll also allow you to add alarms at SOI changes and such, so you don't accidentally miss you injection burn .

3) Build unmanned probe missions first. Nobody in his right mind drops manned missions on the first go. We send robots.

4) Quicksave, use it, love it. There is no shame in it. Alt+F5 even allows you to name them and Alt+F9 allows you to load a specific save.

[Wanderfound]

Duna isn't really any harder to get to than the Mun. The transfer burn is only about 1,000ÃŽâ€V, and the ability to land on parachutes makes touchdown a breeze. Getting back to orbit isn't quite as easy as the Mun, but it's still not hard; thin atmosphere, low gravity.

I suspect that you'll be going a bit more conventionally than this, but the demonstration may be useful anyway:

[DocLangy]

Unmanned first of course.

Get your basics down in Kerbins SOI, make a few more trips to the Mun until you can reliably land and return without it being a nail biter.

Videos helped me as well. Keep up the good work. I've only ever been to Duna and Eve, I've never even seen Jool, it's all a learning process.

[Heartstrings]

Well thanks all of you. At least now I feel like actually playing the game, if just to test these ideas, and that's quite helpful. I'll shoot for the Mun a few more times, then try applying some of this stuff to get to Duna.

[Axelord FTW]

Well thanks all of you. At least now I feel like actually playing the game, if just to test these ideas, and that's quite helpful. I'll shoot for the Mun a few more times, then try applying some of this stuff to get to Duna.

Wait till you start getting *redacted* urges toward mods like TAC, FAR, DRE, Remote Tech...

[Pecan]

The Drawing Board in the tutorials section of this forum is the best place to look for which guide would suit you.

Mine has vehicles for all uses (er, except Tylo, Laythe and Eve) :-)

[Luis]

I would also suggest that you don't try and do the entire mission in one launch. Once you are comfortable with orbital rendezvous you can run your mission in stages. Launch your lander and your transfer stage separately and dock them together in Kerbin orbit. Send an unmanned refuelling ship to Duna ahead of time and leave it in orbit. Your lander just needs to have enough fuel to to a round trip from a low Duna orbit to the surface and back. Everything else you can refuel in orbit.

[problemecium]

I wouldn't listen to these people who are all suggesting you get a bunch of mods like KER, MechJeb, etc. They mean well, and those mods are indeed very helpful, but if you stick with manual controls for now, you'll develop important skills that'll make your life easier later on. A lot of us have played for months and never got the hang of docking, for instance, due to always relying on automated systems, and consequently they have to resort to launching wobbly behemoths for every mission.

What I do recommend is that you make liberal use of the Quicksave system. Feel free to hit F5 every time you successfully complete an important step and before anything dangerous like aerobraking. Before you know it you'll have lots of practice under your belt, or at least have discovered 999 ways not to do something

[Forty21112]

Well, I may not be of help since I've only landed in the Mun today, but I would suggest a good launcher stage.

For me, Booster stages are good to go when they can reach 3/4 into orbit. (And just coast the rest until the apoapsis)

Orbiting stages should get you half or 3/4's the way to your destination.

I can't offer a better way on making, flying or landing stuff, but, you also have to remember that the nail-biting anxiety you get from flying there is nothing compared to the happiness and exhilaration you get when you get there safe and sound. (And mostly intact). Good luck on your Duna mission!

[Frank_G]

I wouldn't listen to these people who are all suggesting you get a bunch of mods like KER, MechJeb, etc. They mean well, and those mods are indeed very helpful, but if you stick with manual controls for now, you'll develop important skills that'll make your life easier later on. A lot of us have played for months and never got the hang of docking, for instance, due to always relying on automated systems, and consequently they have to resort to launching wobbly behemoths for every mission.

What I do recommend is that you make liberal use of the Quicksave system. Feel free to hit F5 every time you successfully complete an important step and before anything dangerous like aerobraking. Before you know it you'll have lots of practice under your belt, or at least have discovered 999 ways not to do something

I totally second this. Building up a good foundation of skill and knowledge is essential to get your ships where and how you want it. It also gives you the understanding of how to optimize craft and give you a feel for things.

[andruszkow]

I feel that one important thing to know about transfering to bodies outside Kerbins SOI, is phasing angles, because it seriously reduces the fiddleing with maneuver nodes and adjustment burns.

You can transfer to all bodies in the system without knowing them, but knowing how the planets should be aligned before trying a transfer to ie. Duna, saves you a lot of fuel, and therefore reduces the fuel requirement of your transfer stage.

I've never tried mods that assists with Phasing angles, but I've learned from these forums, that when you want to transfer to Duna, switch to map mode, zoom out, and time accellerate until Duna is in front of Kerbin in it's orbit around Kerbol (the sun). If you imagine a straigt line from Kerbin to the sun, and a straight line from Duna to the sun, the angle between Kerbin and Duna should be about 45 degrees (I think it's about 44 degrees, but 45 should be just fine). This is the optimal alignment between those two planets for a transfer.

You can use this amazing guide for a graphical presentation of how Kerbin, Duna and your transfer stage should be aligned.

[Nedal]

Also if you don't want to mess with mods and phase angles and such. How I used to do interplanetary transfers was to, eject from kerbin going the right direction. Away from kerbins direction around the sun to go inner. Or faster than kerbin to go outer. Get your kerbol periaps (inner) about matching somewhere on the destination planets orbit. Fix any inclination (burn normal on decending node or vice versa). Then when you get to the periapsis, fiddle with a node until you get an encounter on the next orbit. You may have to time warp a lot. try to manipulate your orbit so that it more closely matches the destination planet, so for duna, you'd want to burn retro grade at the periapsis to get your encounter, not Prograde (this helps not waste deltav once you arrive to make orbit). Overall it's not much more inefficient than using correct transfer windows. You just waste a lot of kerbal years timewarping. Sometimes you have to go around a few times to get a decent node to encounter.

[soulsource]

I also recommend that you don't cheat use mods in the beginning.

The required dV values for Hohmann Transfers (using Oberth Effect) have already been posted here, yet there's an updated version of the map that also gives you the worst case dV required for inclination changes (the numbers outside the coloured lines).

If you want to find out how to calculte these numbers yourself: Check out the two Wikipedia articles I linked above. For the worst case inclination dV requirements, the highest velocity on the transfer orbit (at periapsis) has been multiplied by 2*sin(inclination/2). To derive phase angles, calculate the time it takes to do a Hohmann transfer and look which angle your target planet moves in that time. You'll want your target planet to be that angle before 180°.

In order to calculate the dV of a stage, you'll need the wet and dry mass, the specific impulse (Isp), and the rocket equation. In the latest version of KSP an approximate readout of the craft mass is given in the VAB, so you can simply write it down once with full tanks, then drown all the tanks of the stage (right click menu), and note down the dry mass. Don't forget to fill the tanks again after this. The Isp value of the engines is displayed if you right click the part in the part list.

(Just as a sidenote: In previous versions, where the mass readout wasn't available yet, I was using a spreadsheet and summing up the part masses manually. I managed to do a return mission to Eve like this, but it gets very, very tedious.)

(Just another side note: I've written an alternative derivation of the rocket equation using the fuel consumption as a starting point. I know it's less elegant than simply starting with the change of momentum, but it might or might not be more intuitive)

Edit: There was a mistake in the rocket equation. Thanks Pecan for pointing it out.

Edited January 27, 2015 by soulsource
Ooops, the g*Isp term is of course in the numerator... Copy&Paste...

[merendel]

I wouldn't listen to these people who are all suggesting you get a bunch of mods like KER, MechJeb, etc. They mean well, and those mods are indeed very helpful, but if you stick with manual controls for now, you'll develop important skills that'll make your life easier later on. A lot of us have played for months and never got the hang of docking, for instance, due to always relying on automated systems, and consequently they have to resort to launching wobbly behemoths for every mission.

What I do recommend is that you make liberal use of the Quicksave system. Feel free to hit F5 every time you successfully complete an important step and before anything dangerous like aerobraking. Before you know it you'll have lots of practice under your belt, or at least have discovered 999 ways not to do something

While I sort of agree with the point about mechjeb I have to disagree with adding KER into that mix. It is better to learn the skills behind orbital manuvers vs just haveing mechjeb do them all for you. However KER offers no auto pilot functionality nor will it figure out manuvers for you, just information windows about your craft and situation. Yes you can either math out the dV by hand or with experience eyeball it but I dont really see a good argument for doing that the hard way. Other bits of information KER provides are also avalible in game but not in a convenient format that alows you to see all the data points at the same time.

[eddiew]

1) Install Kerbal Engineer, it'll provide you with per stage dv information ...*snip*

All these points are excellent advice for your first interplanetary

KER will give you the confidence that your ship, on paper, will make the trip and come back by giving you a clear readout of delta-v and thrust-to-weight ratios. Transfer Window Planner will help you optimise your launch date for the most efficient route, and KAC will make sure you don't miss the launch. Optionally, MechJeb will plot that route for you and make a manoeuvre node that you can warp to.

And absolutely, 'bots before boots. My inner RP always points out that you can't be sure about landing conditions until you have landed - so better to land a probe first, or better, several probes.

You could also look into Kerbal Construction Time, which will allow you to run simulations around any planet/moon that you have 'visited' (e.g. with a probe lander). This would let you test out your Duna lander and return vehicle, for example, so that you know that will work, and all you have to worry about is the interplanetary transfer (which is ultimately just a rocket with enough delta-v to push you there).

Also, don't worry about failure! My biggest design error to date also turned into my best mission in the game to date. KSP gives you a wealth of tools for fixing mistakes, and the rescue missions, or the cobbled together solutions you end up with, are often more fun than the original plan!

Good luck!