Balance.

[Jas1126]

Hello. I have tried time and time again to make a proper rocket (Launch stage with a space plane attached to the side) but I can never get it to fly straight. I have come close but it's still an immense struggle to keep it pointed upward. How do you go about balancing it? I have tried putting useless parts here and there to try and get the weight equalized to no avail. Would somebody have a couple of working examples that I can study that used stock parts?

Thank you.

[Yellowburn10]

I don't have any examples to show, but I do have some tips. It takes a little more than making sure the CoM is right, you need to have it line up with the Center of Thrust, or CoT. Where both of them land will depend which way your craft will fly. To help this, instead of putting random parts to even out the mass, use some thrusters and tweak their thrust limiters, to make sure the CoT is directly beneath the CoM. If you have a plane radially attached to your rocket, try to have the CoT line up with your CoL (center of lift) more than your CoM. Also the new RCS nozzles that use liquid fuel are handy to keep your rocket straight during accent, too.

If any of this looks wrong, please correct me.

[Jas1126]

Thanks very much for the tips. Still, I would love to see a functioning design or two if anyone has it.

[Linear]

In .25, one of the default crafts is a shuttle-type launcher.

[worir4]

In .25, one of the default crafts is a shuttle-type launcher.

Even this is immensely difficult to fly. I recommend you use a load of Vernier thrusters to try keep it the way you want it pointing.

[Frozen_Heart]

You have to angle the engines so that the CoT is always going through the CoM.

[MKI]

(Its like 6 in the morning haven't slept yet forgive me for any grammer/spelling issues)

I have been able to make around 2 effecient self propeled shuttle designs out of around 50 prototypes and rebuilds.

Simply put its TOUGH AS NAILS.

Here are a few questionable screenshots of my craft. Its my attempt at making a Space Shuttle design, with SRBS, external tank, with primary thrust coming from the Ship itself. It was my most successful Shuttle designs ever. It was able to reach 10k altitude without ANY control beyond SAS with a near perfect straight up launch trajectory. Beyond that it was able to get to a stable orbit and use its two OMS engines to transfer withing 1100 Delta-v of nearby LKO targets. No cargo capacity sadly, but worked perfectly as a Kerbal Transport unit, going to stations and returning with excellent glide capabilities.(it was simple and light)

2 are closeups of the engine and bottom design. Sorry for the lack of better pictures, i only took these.

NOTE: this design is outdated, as this was before the MK3 part changes and wing changes.

Last I checked this ship became unstable after the changes, so i no longe have its design on hand.

But it was at a great example for its time.

http://steamcommunity.com/sharedfiles/filedetails/?id=252417423

http://steamcommunity.com/sharedfiles/filedetails/?id=252417411

http://steamcommunity.com/sharedfiles/filedetails/?id=253103697

http://steamcommunity.com/sharedfiles/filedetails/?id=252417439

http://steamcommunity.com/sharedfiles/filedetails/?id=252417449

http://steamcommunity.com/sharedfiles/filedetails/?id=253103731

The key to my design, as the propulsion is on the Ship itself is angling of the engines. 4T35's gave me average gimbal. With the outer 2 at higher angle (like 15? or so) than the inner 2. (10 degrees?)

I also tried my best to keep the fuel as high up as possible(hard to see in the pictures) with the decoupler attatched to the Crew Compartment. As a higher placement means the fuel moves less in relation to the center of thrust. The SRBS are also placed low and are tweaked heavily to burn out JUST as the fuel moves to far due to the higher trust from the SRBS.

Simply put this design DOESN'T work anymore(its .24), as the MK3 parts were changed, as were the wings. Your best bet is to keep a few things in mind. But don't get down, the game has added a few things to help us get Asymetric designs under control.

1. Keep things simple. More parts you add more confusing things get. Especially if you add more fuel, as its movement during acent is hard to determine without actually trying it out. More parts you add, more thrust you need and thus more fuel you need. Its a complicated cycle which is unkind to any asymetric ship, as fuel displacement is your enemy and your litterally balancing it above your engines all the way to orbit. (and beyond in some cases!)

2. Keep your fuel "above" your thrust. In my designs the thrust and center of mass allowed a very straight ascent path(possibly 3 degrees off the prograde during straight ascent). If you take off and immediatly starting going past 10 degrees from straight up your design wont work. Without massive changes to your thrust vectoring.

3. Tweak your thrust levels of your ascent engines along with changing the angling of your thrust vector. Minor adjustments can create big effects.

4. VERNOR VERNOR VERNOR- hands down the easiest way to get anything under control. In an asymetric Shuttle Design stick a few of these on the External Fuel tank/stack and you will get MASSIVE control over your ship. This is at a cost, as you now must carry more fuel to keep your ship under control, so putting 6+ on your ship will eat away your fuel reserves. So getting your ship to be close to stable will help greatly.

I plan to remake a new shuttle utiling the new parts and cargo bays.

Vernors can be a big help, but relying on them to much wastes to much fuel when you can make better design choices. Asymetric Shuttle designs are the hardest thing to make in this game hands down. Until we get a high gimbal high thrust engine to compesate for fuel movements and offset centers of mass, we must build our ships perfect.

Goodluck!

Edited October 15, 2014 by MKI

[Bishop149]

I've never even bothered trying this TBH its easier just to launch 2 light shuttles at a time so the weight is always precisely balanced on the either side of the rocket, and you get twice the spaceship for your launch!

The real spaceshuttle goes up with its own thrusters firing while still attched to the boosters / fueltank, so I assume this offset thrust is just enough to balance out its own weight. you could probably achieve something similar in KSP by setting the thrust limiters just so on the shuttles engines. . . . but would take a fair old bit of trial and error to get right.

[cantab]

Space Shuttle alikes are always going to be difficult in stock KSP. The main engines need to thrust through the centre of mass, or nearly so, but said centre of mass shifts around, and no engine in KSP can gimbal anything like as much as the real SSME's did to handle that.

So you might be better off taking the approach used by Buran, with the main engines under the external tank. I would guess they were off-centre so the thrust would be better aligned with the CoM, though there will still be shift in that to deal with.

[turkwinif]

What's the advantage of space shuttles v. regular ol' streamline rockets, IRL and KSP? Now that I think about it, what's the point of using a shuttle in KSP if it's a ton easier to send stuff up and return with a rocket?

[r4pt0r]

the shuttle is a reasonably safe, reusable lander essentially. has good crew/cargo capacity.

[ZedNova]

Here's a shuttle i recently made:

It's all about balancing the center of thrust with the Center of mass, and making sure it stays balanced until the main tank is out of fuel.

Edited October 15, 2014 by ZedNova

[Sandworm]

I think you guys as missing the point with those shuttles. The realworld shuttle was much more than a reusable crew return vehicle. That could be built without the wings, as SpaceX is building the Dragon today. Shuttle's main job, what made it different than a reusable capsule, was to bring back the expensive rocket engines. So any shuttle design that has engines mounted on the non-reusable tank is a shuttle in appearance alone, more akin to the Buran than the shuttle.

[Frozen_Heart]

I think you guys as missing the point with those shuttles. The realworld shuttle was much more than a reusable crew return vehicle. That could be built without the wings, as SpaceX is building the Dragon today. Shuttle's main job, what made it different than a reusable capsule, was to bring back the expensive rocket engines. So any shuttle design that has engines mounted on the non-reusable tank is a shuttle in appearance alone, more akin to the Buran than the shuttle.

How bout this then...

[Alshain]

How bout this then...

http://i.imgur.com/eKL1c7C.png

Yep, that's a shuttle. Strangely mounted, but it's a shuttle.

Edited October 15, 2014 by Alshain

[Frozen_Heart]

Yep, that's a shuttle. Strangely mounted, but it's a shuttle.

Strangely mounted due to the engines having very little gimbal. The other options were even more reaction wheels or relying on RCS.

[Alshain]

Well it's better than the shuttles I've built. I wonder how Scott Manley overcame that, I know he built one during his IQ series.

EDIT: Oh, I guess he

. I may have to try my hand at building one of these. My problem is I'm terrible at unpowered landings. Edited October 15, 2014 by Alshain

[Giggleplex777]

What's the advantage of space shuttles v. regular ol' streamline rockets, IRL and KSP? Now that I think about it, what's the point of using a shuttle in KSP if it's a ton easier to send stuff up and return with a rocket?

It's cooler?

In all seriousness, shuttles allow you to send crew and cargo to orbit and then return them to the surface; what would otherwise require two launches can be done in one.

Edited October 15, 2014 by Giggleplex777

[FishInferno]

What's the advantage of space shuttles v. regular ol' streamline rockets, IRL and KSP? Now that I think about it, what's the point of using a shuttle in KSP if it's a ton easier to send stuff up and return with a rocket?

It's cooler?

Other than being cooler, there is no real advantage. The shuttle just adds dead weight that could be used for more payload capacity.

And I know the whole thing about reusability and all that, but 2 things:

1. The shuttle was still expensive and the reusability didn't help much.

2. If you just stack the payload on a normal rocket, you never need to build the shuttle in the first place!

[Pecan]

There's nothing you can do with a shuttle that you can't do with a rocket, in stock KSP.

There's nothing you can do with a rocket that you can't do more cost-efficiently with a jet-launched vehicle in stock KSP.

Stock KSP is different to that mythical planet 'Earth' that so many people talk about.

[sdj64]

And there's nothing you can do with a shuttle that you can't do with a rocket on Earth either. The Saturn 5 sent up crew and cargo (the lunar lander) combined in one launch, so the Shuttle isn't alone in that capability. The shuttle orbiter had an empty weight of more than 3 times its max payload. If the payload was set inside a simple fairing on top of the rocket it could have saved most of this extra weight.

One important reason for using it was cross-range: The military mandated that if required, it could launch into a polar orbit and de-orbit one orbit later, during which time the Earth moved underneath by 1000 miles. The shuttle could glide back to Cape Canaveral over this distance if it had to. Second reason was for experiments that could be done in a pressurized, reusable lab in the cargo bay then flown back to Earth. Also, as said before, the Shuttle did reuse the expensive main engines, but it's debatable whether or not it would have been actually cheaper. Something like SpaceX's model of flying back the spent stages down to Earth would probably be the cheapest option.

Most of that was taken from the Wikipedia article, you guys inspire me to get lost in Wikipedia so many times...

[Sandworm]

There was one thing that shuttle could do that rockets couldn't. It could potentially bring something back, something that was in orbit and needed to be brought down. Remember that it was Nixon that OKed the program. This capacity to return material was certainly the driving force behind Buran.

(1) Capturing, stealing, a piece of Russian/enemy hardware. Possible in theory, but extremely difficult and impossible to accomplish quietly.

(2) The maintenance of on-orbit weapons systems. Any orbital weapon could never be allowed to fall from orbit. You cannot de-orbit an old nuclear missile. You have to pack it up and bring it back in a controlled manner. Shuttle never did this, but in the the days of the real starwars programs such things were contemplated.

[LethalDose]

Other than being cooler, there is no real advantage. The shuttle just adds dead weight that could be used for more payload capacity.

And I know the whole thing about reusability and all that, but 2 things:

1. The shuttle was still expensive and the reusability didn't help much.

2. If you just stack the payload on a normal rocket, you never need to build the shuttle in the first place!

Well, the reusability didn't help much because IRL it never lived up to the hype. Shuttles were originally supposed to have a 2 week turn around, but... reality. We don't have that issue as much in KSP.

I think you guys as missing the point with those shuttles. The realworld shuttle was much more than a reusable crew return vehicle. That could be built without the wings, as SpaceX is building the Dragon today. Shuttle's main job, what made it different than a reusable capsule, was to bring back the expensive rocket engines. So any shuttle design that has engines mounted on the non-reusable tank is a shuttle in appearance alone, more akin to the Buran than the shuttle.

The ability to bring back those expensive engines is still a "reusability" issue, though.

[Pecan]

There was one thing that shuttle could do that rockets couldn't...

NOT in KSP, which is the point I made. It is easier to make a rocket or even a spaceplane that is balanced and recoverable, in KSP, than it is to make anything like the monstrous, unbalanced, 'Earth' shuttle. The tricky bit, in fact, is making a rocket/spaceplane that is balanced and flies/lands well either with or without a payload, so in some ways it's simpler to land with one than without.

[Alshain]

NOT in KSP, which is the point I made. It is easier to make a rocket or even a spaceplane that is balanced and recoverable, in KSP, than it is to make anything like the monstrous, unbalanced, 'Earth' shuttle. The tricky bit, in fact, is making a rocket/spaceplane that is balanced and flies/lands well either with or without a payload, so in some ways it's simpler to land with one than without.

There is one thing in KSP that building and flying Shuttle can do that a rocket or SSTO Spaceplane can not do... it can prove your ability to build and fly a Shuttle.

Why build a station?

Why go to the Mun?

Why build a rocket?

Why play the game at all?

All of those can be answered the same way you would answer "Why build a shuttle?"

Answer: Because it's fun.