Pecan

A little thing to watch out for is that not all fuel tanks are equal. The very small and 3.5m tanks mass more per fuel unit they contain than the others. The very small tanks are more expensive per fuel unit as well.

merendel and magnemoe - thanks for those examples, I'll be chucking them into the mix to see what comes out :-) Keep 'em coming.

Yeah, you're probably right. It isn't nearly wrong enough for stock - 40t payload is too much for newbs too. I'll dig out one of my 2t 'fails' for you tomorrow. Oh, wait a minute - how about Bantam. It handles well at low-speeds and altitudes (~60m/s take-off and landing) while also being able to reach orbital speeds and altitude on less than 50 units of fuel, leaving ~50-60m/s for rocket circularisation. Should you be scared of space for some reason there is enough jet fuel to circumnavigate Kerbin entirely within the atmosphere. Bantam light spaceplane The 'flaw' is that it still uses air-hogging. Take most of the intakes off for a perfectly normal spaceplane that still works better than anything in stock. Replace one of the fuel tanks with a 'cargo bay' if you want to carry payloads.

This is another spaceplane. SP 40 B with Fuel Module payload It's almost good - it shows you how to balance a payload so it can be detached without making the 'plane unflyable. It could put any payload you like, up to 40t, into a 75km+ circular orbit. It is, by spaceplane standards, fairly low-part. The tiny flaw is that it no longer works in 0.25. Won't even take off. Hint: is it just a problem with rear landing-gear preventing it rotating?

As with my question to Sivert, can you say what you mean by 'significant payload', as I'm finding SRBs don't add significantly to payloads over about 10 or 20t. I'd love more information and examples for this, whether I'm right or wrong, because I'm about to start writing a tutorial on exactly this subject. It would be nice to get it right!

As Laie said the tri-coupler makes a good-looking rocket. It's in there at the tech-levels you've reached but I can't remember exactly which and the design that Umbralraptor ninja'd me with is the same, just tanks connected straight to each other rather than the tri-coupler, so you don't really need it except for looks. Minmus is harder to reach, especially because of the plane-change but that's a manoeuvre you ought to practice because you'll need it quite a bit. Having got there the low gravity and big, flat areas make it so much easier to land on and re-orbit from that overall it's the easier mission. Even if it doesn't look like it, Minmus really is a lot better for a first landing than Mun. If you're not landing Mun is much better because it's easy to get to and has more biomes for science.

Sivert3, this is all great data but could you run a plot with a more interesting payload? 5t and that is too small for anything outside Kerbin's system so what do you make of the 10 - 50t range? As far as I've been able to check (quite a bit but not enough to publish) SRBs stop being cost-effective for anything but small loads, making SSTO rockets quite attractive.

The traditional way to measure "the lightest possible launcher for a given payload" is the Payload Ratio. Many people will already have this figure calculated for their launch vehicles and it'll help compare results here with other threads and equations if you use that measure. For KSP rockets 10% is 'acceptable', 15% 'efficient' and 20% sometimes obtainable. Can't find the thread yet but a few people have broken the 20% barrier and you should expect several entries in that range. For jets the ratio is more like 60%, somewhat lower for spaceplanes as they have to drag wings and landing-gear with them. Payload Ratio always was the way launch-vehicles were judged in KSP before 0.24 because mass was almost the only way to measure them. Since cost and recovery now count as well you might like to look at the other 'cost effective' launcher threads too.

Congratulations and applause - realising it can be done and being inspired to do it are the first steps :-) Make the thread 'answered', it doesn't stop people commenting any more and shows that useful answers are contained.

Replying to a 2-year old thread to say "I think there's a mod for that"? The Mk2 cockpit they're talking about isn't even the Mk2 cockpit we have now. Lock it sal_vager, lock it.

Control surfaces are automatically replaced when you open the .craft file. There is no difficulty copying ships between 0.24.2 and 0.25 - apart from the fact that some of them just don't fly any more.

Yes. Ride 'em, Space Cowboy

How do you do that for sandbox? @Fendleton: Do you mean it's a good starting-point in that it shows you why you shouldn't do it but if you do you shouldn't do it like this? (Honestly, I can't tell if you're joking).

Huh? Do you mean the Harrier family such as the AV-8B? SSTO rockets are not just possible, they're easier. They're good for a much wider range of payloads - especially things too heavy for 'planes to handle without exrensive mods and/or thousands of parts. The part count is way lower than a spaceplane for an equivalent payload (except where the payload is very light). There is absolutely no need to fiddle with the throttle. Even if there were they'd still be a hundred times less difficult to fly than spaceplanes ^^. Spot-on there though. SSTO rockets absolutely drink fuel. My standard 100t-payload SSTO rocket only manages 13.5%. Of course, if you build a VTVL SSTO with jets you get all the fuel-benefits that spaceplanes do and still don't have to drag all those extra, massy, useless parts (like wings) along with you so you get the best payload ratio possible.

I believe you, because I read the change log in the readme.txt "Added a new stock craft, the Learstar A1: A hybrid multistage vessel that functions very much like the Shuttle did." Like all other stock vehicles, I deleted it. I can always unzip them again in the unlikely event that I want to fly a bad vehicle.

Alright, everything except the spaceplanes is ok. "Trainer" will be replaced with "Trainer C" (don't ask what happened to "B") "Crew Shuttle SP" will be upgraded to "Crew Shuttle +" If a miracle occurs I may even get those updated tomorrow, otherwise it'll be some time during the week. The text (PDF first) will take at least until next weekend.

For a guide that will show you 30-odd designs and 50-something missions from a simple rover to spaceplanes and interplanetary rockets you might like to look at the tutorial in my signature. Mods that I recommend there are mainly informational ones because stock KSP doesn't give you a lot of the information you need for designing vehicles - Kerbal Engineer Redux (KER), VOID (full name too long to type) or MechJeb (MJ, also an autopilot). Another very useful one once you have several flights in progress at once is Kerbal Alarm Clock (KAC), but you don't need that when you're just starting. Actually used in the tutorial are SCANSat (for mapping satellites) and Procedural Fairings (aesthetics) but you don't need either those or anything else to build and fly the craft. I am currently updating it for KSP 0.25 though and must warn you that the trainer aeroplane is almost unflyable :-( Everything else tests ok so far.

SSTO = Somewhat Simpler Tall Object.

Tutorial required! Get writing/filming ^^.

Yes, exactly what I'd prefer if it was me. Comfortable rocket SSTO launches, section-assembly in orbit, final construction at destination.

In 0.25 there are icons on the space centre screen itself showing where vehicles and debris are around KSC. You can click these to recover (or fly) different things without going via the tracking station.

You can imagine all forces acting on, or around, the CoM. A force going directly through the CoM will push the vehicle in that direction, out of line it will tend to rotate the vehicle. So if all your engines are above the CoM they'll be pushing the top of the vehicle more than the bottom, making it tend to tip nose-down. CoL works the same - if it's behind the CoM it will tend to make the plane nose-down, if it's in front it will tend to make it nose-up (off to the side, the plane will roll, etc.). While a plane that wants to go up sounds good in practice it makes the vehicle to prone to flipping which is why standard designs put the CoL just behind the CoM - too far and it'll be too hard for other things like wings/control-surfaces to counteract and the thing will never get off the ground.

I'm glad you did though - I hadn't heard of VTVL before either but it might be handy for making the distinction between something that is meant to launch/land and fly 'vertically' and something that can launch/land vertically but fly horizontally. (... until 45-degrees of course, then I'm just stuck again ^^)

1. Not very big because you'll use very efficient LV-N engines for the space-only operations. 2. Depends on how good you are at designing one, but 10% payload-ratio is the minimum you should aim for, 15% can usually be done and 20% is sometimes possible. If you use a jet-powered launch vehicle you can do a lot better than that. 3. None at all, unless you are using one or more mods you aren't telling us about.

A 100t-payload SSTO launch vehicle would be your best option, but harder to build and fly (especially land), since then you can get all, or at least a large part, of the craft cost back once you land and recover. Launches that only cost fuel are cool ;-0 Talking of which - if you are launching fuel tanks amongst that 600t, try sending them up empty and refuelling them later. That way your 'huge' lift only has to cope with a smaller mass in one go. As a rule, use engines with the best ISP, work out what they can lift and go with that. Bigger payloads (>100t) tend to result in less efficient vehicles because of diminishing returns, but it can be done.