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[STOCK] Space Shuttle "Resolution"


Naito

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Beautiful! Did you make the modules? I would like to see those as a complete station.

Thanks!! Yes, they're linked in my sig and on the first post in this thread. I haven't had time to play much lately though, so it's still just Zarya and Zvezda right now =(

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Thanks!! Yes, they're linked in my sig and on the first post in this thread. I haven't had time to play much lately though, so it's still just Zarya and Zvezda right now =(

LOL turns out I repped you for them already. I am a silly sausage. I love the look of them, good luck with the project mate.

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  • 4 weeks later...
  • 2 months later...

First of all let me say I absolutely LOVE this ship. I've spent countless hours trying to make a shuttle in KSP that handles properly and could never get anywhere close to getting it right. This took me a couple nights to figure out how to fly it properly and I've pretty much figured it out. I've got a ton of time flying traditional rockets in KSP but I'm sort of a noob with spaceplanes.

 

I have two problems that I hope maybe you can give some advice on. First, because the thrust is offset from the cockpit axis, I'm finding it hard to accurately burn at maneuver nodes. I pitch the nose up approximately 10 degrees above the node when I burn which gets me in a fair approximation of where it should be, but I still wind up having to make a bunch of corrective burns afterwards. Trying to get a precision orbit (much less rendezvous) is real tricky. Any advice on how I can better aim the ship when I'm flying in orbit?

 

Second, when I'm landing, I usually lose control and start to tumble around 25km or so. The ship rolls left to right, getting more aggressive with each roll until it rolls 90 degrees to one side, and starts to tumble end over end for a full minute or two before I can regain control and land. Any advice on how to keep it stable? I usually come in at a fairly shallow re-entry, starting around the burn 100km altitude and ending with a periapsis targeted around 15km or so.

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This ship is a bit old and not fixed for the current version, someone fixed the tumble with some clipped in rear elevators for shuttle style craft, maybe try that. You should probably look for more current craft if you want it fixed for you. My shuttle replica works in this version, but quite small compared to the above.

Here you go heres the fix from Flakbadger

 

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Thanks selfish_meme! I wanted to avoid putting any other fins on the craft if possible, but I hadn't considered offsetting them into the body to hide them.

Now, if only I could get the navball orient to the direction of thrust instead of dead-forward from the cockpit, I'd be perfectly happy. My less-than-optimal solution has been to add a probe core at the same orientation as the SSMEs and use it as the "control from here" part whenever making a burn to reflect the actual direction the ship will fly.

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I am, yeah. Positioning the probe core in the middle of the SSMEs hides it from being an ugly protrusion at the back of the craft. It's close enough to the OMS center of thrust that it's "good enough" to get me to where I want to be within an acceptable margin of error.

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  • 4 months later...
On 1/21/2016 at 10:01 AM, devikwolf said:

First of all let me say I absolutely LOVE this ship. I've spent countless hours trying to make a shuttle in KSP that handles properly and could never get anywhere close to getting it right. This took me a couple nights to figure out how to fly it properly and I've pretty much figured it out. I've got a ton of time flying traditional rockets in KSP but I'm sort of a noob with spaceplanes.

 

I have two problems that I hope maybe you can give some advice on. First, because the thrust is offset from the cockpit axis, I'm finding it hard to accurately burn at maneuver nodes. I pitch the nose up approximately 10 degrees above the node when I burn which gets me in a fair approximation of where it should be, but I still wind up having to make a bunch of corrective burns afterwards. Trying to get a precision orbit (much less rendezvous) is real tricky. Any advice on how I can better aim the ship when I'm flying in orbit?

 

Second, when I'm landing, I usually lose control and start to tumble around 25km or so. The ship rolls left to right, getting more aggressive with each roll until it rolls 90 degrees to one side, and starts to tumble end over end for a full minute or two before I can regain control and land. Any advice on how to keep it stable? I usually come in at a fairly shallow re-entry, starting around the burn 100km altitude and ending with a periapsis targeted around 15km or so.

Wow it's been a long time since I signed in =) Super old bump and reply!

Thanks for the compliments Devikwolf!!  Glad someone's still flying this!!

I actually JUST tested it on 1.1.2 now (this is the first time I've fired up 1.1.2 lol), and it seems to fly fine to me.  I was able to get it up to a circular 500km orbit and back using the same "realistic" flight profile as I used to fly (auto-pilot Radial mode out to about 2km-ish, then switch to prograde, roll to heads up about 30s after booster separation), but was with an empty cargo bay.

Maneuver nodes are tricky.  I don't really have any good advice for that, I've always just ended up overbudgeting on fuel to make up for it.  I was working on a version that has gimbalable OMS engines instead, but never got around to finishing.  Other "trick" I'd thought of trying was putting in a small probe core that was properly offset along the thrust axis so that you can switch to controlling from there for burns, but again wasn't something I got around to before I stopped playing. (ninja edit: looks like you already did this! does it work ok?)

For landing, couple tips.  Make sure you dump fuel to bring your CG forward as much as possible, you should only need a little bit for the entry maneuvering.  Keep your nose high about 30 degrees up from the direction of travel, you should be able to do S-Turns.  I usually have it set to just stability assist during re-entry.  From 100km altitude I'd aim even more aggressively for the periapsis, there's a lot of hypersonic life when you keep your nose that high.  Nose down once you get past the heating stage (around 1200m/s I think), and try keep your speed up above 150m/s or so during the glide or you won't be able to pull out in time.

Really glad someone's still enjoying this craft =)

Edited by Naito
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Updated for 1.1x

https://kerbalx.com/Naito/KSP1-Shuttle2016

MWV7hV9l.jpg

New for this version:

  • Uses new KSP SSMEs
  • Certified to launch 0 to 68T without adjustments! (4 full Ore tanks to 100km!)
  • Vernier engines as well as RCS for maneuvering
  • Redesigned OMS pods now use Fuel+Oxidizer rather than Monoprop. Shares fuel with fuel cells and vernier thrusters. SSME fuel is still isolated from rest of shuttle systems so you can safely burn to ET fuel exhaustion and still have OMS fuel remaining!
  • hybrid boosters (SRB integrated in LRBs to provide a bit of extra thrust and more dramatic exhaust effects)
  • additional control point added beneath rudder for better alignment when using maneuvering nodes
  • Reduced part count!

Should otherwise fly just like the previous version!

The control point under the rudder is just a small "probe" that is better aligned with the craft's CG when in orbit.  It should help make using maneuvering nodes more accurate.  Just switch between controlling from there and the cockpit as required.

Edited by Naito
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Nice thing about all the extra power the new SSMEs provide is this thing actually becomes a fairly useful launcher :)

Y2aKLPQl.png

uhUtVeLl.png

I can upload the com-sat as well if anyone's interested.  It's pretty basic really.

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1 hour ago, XpertKerbalKSP said:

Duuuude, for some reason (using the KS-25s) I can never seem to do a stable roll. I roll for a bit, then it yaws, pitches, etc.

Can you give me some advice for making my shuttle be able to roll? eg. what engines I should use, or the engine alignment, etc.

Are you talking about your Voyager Shuttle?

I tried launching it, but it loses control quickly if you pitch at all within the atmosphere.  That's pretty typical of top mounted spaceplanes though; there's a reason why the Boeing X-37 and other top-mounted spaceplanes are enclosed in a fairing nowadays.  It doesn't have anything to do with the KS-25s, if anything the super-gimbal range of the KS-25s might keep it flying straight a little longer, but the top mounted wings will still tip it over eventually.

Couple ways to get around that:

1 - put a fairing around the whole winged orbiter (con: extra weight)

2 - launch really slowly until you fly out of the atmosphere (con: lots of gravity losses)

3 - put even bigger wings on the bottom of the rocket (probably still won't work unless you combine it with #2)

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On 6/10/2016 at 8:25 AM, Naito said:

Are you talking about your Voyager Shuttle?

I tried launching it, but it loses control quickly if you pitch at all within the atmosphere.  That's pretty typical of top mounted spaceplanes though; there's a reason why the Boeing X-37 and other top-mounted spaceplanes are enclosed in a fairing nowadays.  It doesn't have anything to do with the KS-25s, if anything the super-gimbal range of the KS-25s might keep it flying straight a little longer, but the top mounted wings will still tip it over eventually.

Couple ways to get around that:

1 - put a fairing around the whole winged orbiter (con: extra weight)

2 - launch really slowly until you fly out of the atmosphere (con: lots of gravity losses)

3 - put even bigger wings on the bottom of the rocket (probably still won't work unless you combine it with #2)

Well, thanks for checking out my craft, but no :P.

I mean when I try to make a real Space Shuttle replica, my shuttle cannot roll because it pitches and yaws out of control.

Thx for checking out my Voyager Shuttle anyway! :P:)

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49 minutes ago, XpertKerbalKSP said:

Well, thanks for checking out my craft, but no :P.

I mean when I try to make a real Space Shuttle replica, my shuttle cannot roll because it pitches and yaws out of control.

Thx for checking out my Voyager Shuttle anyway! :P:)

Ah my bad, you mean in general?

Well the real shuttle uses gimbalable SRBs and the SSMEs to help it roll and maneuver during launch.  If you use SRBs in KSP, you're gonna have a hard time rolling because SRBs in KSP still don't gimbal, so you're reliant on the SSMEs to maneuver.  Inigma's SRB shuttle overcomes this with a ton of SAS units to induce the necessary torque, I used liquid engines instead partly because of the gimbal difference.

Secondly make sure the "neutral" state of all your engines point towards the CG of the ET and Shuttle as closely as possible.  The closer they are, the more they can gimbal in every other direction for maneuvering.  If they point straight up, then you use up almost all of your gimbal range already just pointing towards the initial launch CG, leaving much less available to adjust course and roll etc.  That'll make your shuttle more likely to pitch and twist out of control whenever you try to give it any control inputs.

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11 hours ago, selfish_meme said:

You don't need huge amount's of SAS but it needs to be placed in the right spots, like a tripod.

That's one way to do it yes.  THIS shuttle doesn't use ANY SAS modules anywhere though, even with the current payload abilities =)

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Made a small "big" update =)

Revision 2.2: GPC OPS modes

The Space Shuttle General Purpose Computers (GPCs) were rather old and could not really handle the operations of the shuttle orbiter all at once, being simultaneously a rocket, spaceship and airplane. Thus the GPC software was divided into multiple OPS modes. Each was specialized in a specific area of flight.

This KSP shuttle sorta simulates this by having 4 distinct control points: Cockpit, Docking port, Orbit computer, Re-entry computer.

  • The cockpit is obvious, it defaults to a 0 degree alpha making the orbiter fly most like an airplane. This is also the preferred mode to fly during initial launch while SRBs are attached.
  • The docking port is also pretty obvious, it is best used during docking operations
  • There are TWO additional control points located below the rudder and above the center SSME.  The lower one is the "on-orbit ops" mode computer.  It defaults to a 15degree alpha, which points the OMS engines better through the CG of the orbiter in orbit, allowing for more precise adjustment burns.

  • The upper one is the "re-entry" mode computer.  It defaults to a 40 degree alpha, which corresponds to the recommended re-entry angle for optimal heat control and S-turns.

Switch to the Orbit computer once you separate from the ET. Recommend you keep it here for the duration of on-orbit operations, aside from docking.

For Re-entry, the new re-entry mode makes S-Turns a cinch!

  • Switch to the Re-entry computer once you complete your de-orbit burn and select hold prograde
  • You’ll now be able to complete proper S-Turns simply by using the roll controls. The computer will keep you at the proper 40 degree nose up position.
  • Switch to the Orbit computer once you’re down to about 1300m/s, you’ll see your pitch trim saturate about then.
  • Switch to stability assist mode, and switch back to the cockpit for control and land from there!
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1 hour ago, FCISuperGuy said:

Very interesting way of simulating the GPCs! Mind if I borrow the idea on my own shuttle? You'll get full credit, of course.

Of course you can! :)

 

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