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I keep quitting because of this one single reason.


Dragonchampion

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Like a lot of people, I was really annoyed for a long time that I couldn't make an SSTO. Eventually I did manage to make a few that worked, did some missions with them, and haven't used them since. In the end, as cool as they are, there's nothing they can do that isn't much easier with rockets.

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Another thing to keep in mind here is that spaceplanes in the game are easy compared to real life. Just look how many orbit capable SSTO spaceplanes there are IRL. Nope not one as of yet. Of course they are working on it and have several concepts but none have come to fruition yet.

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SSTOs are never really necessary for anything. They can get you better fuel usage, it's true, but it also ups the challenge factor considerably. It only gets worse if you have NEAR or FAR installed (or I suppose with the new stock aerodynamics for 1.0), as suddenly you have to worry about the actual nature of lift instead of just having the right overall position of center of lift relative to center of mass.

As a veteran of building SSTOs in both current-stock and FAR aerodynamics, I can give you some good tips, though.

1. Center of lift should be slightly behind center of mass, always. A little above or below isn't that big a deal, but behind is essential! As an aerospace engineer once put it, "an airplane with its center of lift behind its center of mass will fly poorly, an airplane with its center of lift in front of its center of mass will fly once".

2. Center of mass should not change meaningfully as fuel drains. This is the biggest engineering hurdle, hands down. Thanks to tweakables, you can see how fuel affects your center of mass as it drains by draining the tanks of fuel in the VAB or SPH, so this is less of a problem than it could be to engineer. It's still what kills most spaceplanes on the way up to orbit, though!

3. You need more wings than you think you need. A good rule of thumb is that your craft should have a wingspan at least as wide as it is long. It's very easy to tell if a craft does not have enough wing surface area, as it will have a very hard time even getting off the ground.

4. You need more engines than you think you need. The high-altitude turbojet and RAPIER engine both can lift about a 16- to 20-ton craft reliably. That's pretty lightweight, all things considered. And of course, you have to remember that their own weight also has to be lifted...

5. Control surfaces are your friends. Some long control surfaces on the rear wings, a vertical control surface on the tailfin, and two horizontal adjustable winglets on top of the tailfin will give you roughly the same control authority as a commercial jet plane has. Stick a pair of adjustable winglets as far forward as possible too for extra control.

4. Know your change-over point! Even a well-built SSTO can still get caught in a flat spin or aerodynamic failure state. Depending on how many intakes you have on your vessel (more is good, but too many is kinda cheat-y), you'll probably be in danger of a flame-out with the turbojets and/or RAPIER engines around 22000 to 24000m. Keep an eye on your IntakeAir, and switch over to rocket engines as soon as it gets down to 0.01 per engine. It's advisable you set up an action group for this, and also set that action group to toggle the air intakes (which are a liability in rocket mode).

5. Know your ascent profile too! Early on, you want to gain altitude and speed both, so keep around 45 degrees. As you reach 8000 to 10000m, you can start slowly making your way to pointing closer to the horizon, as the need for horizontal speed will increase and the need for vertical speed decrease. By 20,000m, you should be nearly in level flight, climbing at a very slow rate but gaining alarming levels of horizontal velocity. Once your speed is getting pretty high (depending on your build, anywhere between 1200 and 1750m/s, start aiming more upwards. As soon as you reach the switch-over point to rocket engines, you'll want to be aiming as up as you can. Aim for an apoapsis of around 100000m for best results, and keep an eye on it; if it dips back into the atmosphere before you reach your peak, push it back up.

6. Don't be afraid to re-engineer your craft! If you don't have enough fuel to circularize once you reach orbit, you need to design your craft around a larger fuel capacity. If you can't seem to stay stable, you need to make your craft more aerodynamic (especially in FAR and the coming 1.0 stock aero!). If you find your jet engines cut out and put you into a flat spin, you need to change over to rockets at a higher level of IntakeAir.

Hopefully some of that will help you. Best of luck to you!

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Is there any way to remove the legs afterwards? I don't do bases like that because I feel that's not a base... that's a giant rover. That's why I've been looking into SSTO;s I've seen so many good bases (http://i.imgur.com/vCHFTi1.png is the best I have seen) but I don't know how they get the actual pieces there. I see no wheels, so they couldn't have driven them, and I remember a while back I saw how someone used a SSTO to deliver the pieces, airdropping them in with parachutes.

*snip*

That helps a lot. I will try to make another one this afternoon. I didn't know about the "never have enough engines or wings" part. That's probably why my first one didn't take off.

Edited by Dragonchampion
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Is there any way to remove the legs afterwards? I don't do bases like that because I feel that's not a base... that's a giant rover. That's why I've been looking into SSTO;s I've seen so many good bases (http://i.imgur.com/vCHFTi1.png is the best I have seen) but I don't know how they get the actual pieces there. I see no wheels, so they couldn't have driven them, and I remember a while back I saw how someone used a SSTO to deliver the pieces, airdropping them in with parachutes.

That base was built on-site using Extraplanetary Launchpads, given its size, shape and the presence of "rocket parts" containers.

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Other than that you might be able to use KAS to pull the legs off?

I never considered making wheels removeable by KAS. That would solve a lot of problems.

That base was built on-site using Extraplanetary Launchpads, given its size, shape and the presence of "rocket parts" containers.

Really? I have EPL, but I always thought that you need a fully functional base BEFORE starting to produce things. After all, Kerbals at your base will die if they don't have food/water/oxygen.

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Why can't a base be a rover or a rover a base. It has several Hitchiker Cans and a Mobile Science Lab. It can't be a Mobile Science lab if it's not mobile! :P

But if you want to you can use radial decouplers and the little SRBs to jettison the legs and rockets after you land like this...

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I didn't like the little rover attached on the nose so I kept the landing legs and relocated the rover to hang underneath.

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Covered parking! :D

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Wait for 1.0!!

All this will change. Should be for the better. The fuel flow logic is changing to keep a more stable CoM as well as no more asymmetric flame out. Also the new aero and stability guides in the SPH should be a welcomed change. In saying that we cant be certain that it will make it easier as atmospheric affects and changing ISP's will make it a big game changer.

This, trying to learn about planes now will be pretty pointless as they will change a lot in 1.0, all the other stuff who don't include atmosphere will not change much so do anything else.

Took years for me to make my first successful SSTO plane. SSTO rockets on the other hand is pretty easy, its just an rocket who has 4-500 m/s left then it reach orbit.

An 3.75 meter stack with an 24x4 engine can deliver 18 ton to LEO then return to KSC. This will probably change to because of re balance and new aero will make it harder to do pinpoint landings.

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Everything, at one time or another. They don't always fail in the same way. The sole shared feature is that they fail.

Well, there are a lot of ways for a spaceplane to fail.^^

I recommend just taking your best plane and going to the FAR thread (if you're using the mod) including some screens? Although, considering you're a lot longer here than me and put so much time into spaceplanes, I have to wonder if you already tried that. It just doesn't seem to be that hard to me, Often annoying or tricky, but not impossible.

B9s sabres are btw a secret weapon for spaceplanes. They reach ridiculous speads on liquid fuel alone, which makes Spaceplanes soooo much easier.

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Holy cow! That's almost exactly what I was looking for. I'll either try this, or do it piece by piece and use detachable rover wheels to move them in position. Thanks!

Removable wheels... I seem to remember seeing a tutorial on base building that was quite good...Temstar's The Art of Modular Base Building.

Links to KSP Base Building videos...

http://www.google.com/?gws_rd=ssl#q=ksp+base+building&tbm=vid

I am sure there are other good tutorials out there. But as others have said, with the release of 1.0 you will probably have to modify your delivery system.

It can't hurt to practice building them in the SPH and rolling them out on the grassy field on either side of the runway to see how they will fit together until then.

Please post pics of your accomplishments!

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You usually don't fly SSTOs to other planets.

...but occasionally you do. :)

This was for FAR, so it won't be directly applicable to the OP (who is using stock aero AFAIK), but as a demonstration:

Edited by Wanderfound
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In real life, real space agencies have managed to achieve orbit, land probes on Venus, Mars, Titan and even a comet, dock spacecraft, land humans on the moon, send probes to bodies in the outer solar system, even have one probe photograph another one as it was entering the atmosphere of another planet.

No one has ever made an SSTO, winged or not!

And according to Elon Musk, who seems to know a thing or two about spaceflight, on planet earth this isn't done because for such a project, "success isn't one of the possible outcomes".

So if SSTOs are not part of the way you do spaceflight... so be it!

Also, dumping stages is great: it's in-flight part count optimization. :)

Having said that, I am surprised by the number of people who have considerable skill building and doing pretty much anything, except SSTO planes. (A few weeks back there was a tread where many people voiced similar experiences.) It seems many people learn how to dock Gilly to Ike in a polar orbit around Jool before achieving LKO in a plane, if I may exaggerate slightly. This puzzles me as this great community has put out many comprehensive guides to building planes.

http://forum.kerbalspaceprogram.com/threads/52080-Basic-Aircraft-Design-Explained-Simply-With-Pictures

http://forum.kerbalspaceprogram.com/threads/65638-Basic-Airplane-Space-Plane-Aero-Tutorial

http://forum.kerbalspaceprogram.com/threads/46067-Spaceplane-SSTO-Troubleshooting-Guide

As others have said, don't try learning planes before 1.0 comes out.

Edited by n.b.z.
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Why can't a base be a rover or a rover a base. It has several Hitchiker Cans and a Mobile Science Lab. It can't be a Mobile Science lab if it's not mobile! :P

But if you want to you can use radial decouplers and the little SRBs to jettison the legs and rockets after you land like this...

or you could right click the command pod and reclassify it as what ever

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Or as fun as a rocket! Having said that.. Landing one from orbit is very satisfying.

I have to agree with this. Rockets are nice and convenient and all, but successfully making an SSTO is one of the best feelings.

I made one that had a payload fraction of 60%. It was great.

Never underestimate rockets, though. They can do everything an SSTO spaceplane can do. And SSTO spaceplanes can do everything rockets can do. It just might require more time...

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Honestly, SSTO aren't impossible : I read a few guides and managed to make an un-efficient one on my first attempt.

My second attempt was good enough to become efficient once I mastered the proper ascent profile. 20 launches later, I'm confident I can use it to bring 55% of an orange tank in orbit every-time (for 2,000 Kredit worth of fuel). Granted, it isn't always easy to fly (it behaves in yaw between 27K and 33K), but I like plane flying anyway.

However, I use it for refueling (launching empty allows me to keep all my payloads under 25T) and ferrying between Kerbin and LKO and back. I personally don't see the point of bringing them further than LKO, they aren't going to be as efficient as my transfer stages.

I made a quick tool to allow me to switch mk2 fuselage sections, so i can easily make Cargo, Fuel and Crew variants (any combination, really), but I'm too late in career for these sat contracts to be worth it, and mk2 bays are too small for bigger things.

I think mk3 isn't as easy, but mk2 is enough for my needs. If i hadn't managed to make it work, i would have launched the fuel/crew pods with conventional launchers anyway, so SSTO aren't really required for a successful career. But they sure save money.

My design (to show that it isn't complicated, I didn't even follow the "intake at the back" advice). it has been refined slightly since:

c7BRKsy.png

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M SSTOs never have enough fuel to do anything once in orbit. So I stick to the tried and true, rockets. Not to mention it takes a while for SSTOs to get into orbit...

Just go fast in the upper atmosphere and bring along only the bare minimum of rocket engines.

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You should download one that's actually functional, follow the manual, see if you succeed and build your own.

SSTOs are super useful when playing on ultra hardcore difficulty in carreer mode.

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Yeah, SSTOs are pretty fun to build (especially landing them as majorjim said), but overall their use is pretty limited. Even some of the best designed SSTOs tend to carry up a fraction of what a rocket can. I like building shuttles though. They are quite challenging and fun to use. With stage recovery they also can be quite cost effective, unlike the real Space Shuttle. It's the best of both worlds: the fun of launching a rocket and the fun of landing a spaceplane/SSTO.

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I have to agree with this. Rockets are nice and convenient and all, but successfully making an SSTO is one of the best feelings.

I made one that had a payload fraction of 60%. It was great.

Never underestimate rockets, though. They can do everything an SSTO spaceplane can do. And SSTO spaceplanes can do everything rockets can do. It just might require more time...

Spaceplanes are cheap to operate, they have two downsides first they are less flexible you can always upgrade an rocket with some boosters and easy make specialized rockets for oversize payloads.

Just adding an fuel tank or an small cargo bay segment to planes require rework and testing. Second takeoff and landing take far longer time.

I end up with using them mostly for crew and resource supply, rescue and interplanetary probes. For satelites around Mun, Minmus and Kerbin I found two trashcans did the work well enough.

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My advice for spaceplanes would be to start small, this was my first successful design...

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Just one turbofan, two ram intakes and two small 48-7S rocket engines.

Once you get the basic principles Centre of Mass / Centre of lift etc. and the launch profile right then you can scale up to bigger craft fairly easily. By the souns of it your main problem seems to be asymmetric flameout causing your craft to spin which is why I would start with a single engine design. I think that this asymmetric flameout problem is being dealt with in update 1.0 so you may have more luck with your designs then anyway. they're also adding a few tools to make aircraft design a bit easier which should help.

Don't give up, you'll get there and it's very satisfying when you do. :)

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