SkyHook Posted May 11, 2013 Share Posted May 11, 2013 (edited) I am trying to build a shuttle using B9 parts and FAR, and I need help! I have managed to build a shuttle that lifts of well at 80% throttle, but the weight imbalance caused by draining fuel is too much, and it eventually tips over, overwhelmed by the weight of the shuttle on its back. I have found a plugin that dynamically controls thrust (which may or may not be enough to stop the imbalance), but before I edit the config files of ALL of my engines, I wanted to turn to the community for advice. Has anybody successfully built a space shuttle in the NASA configuration? if so, what are you tips? Pics would be appreciated CoM, CoT, and CoL MarkersThe complete shuttle.The involuntary tip of death :/Uploaded with ImageShack.us Edited May 14, 2013 by SkyHook Link to comment Share on other sites More sharing options...
mushroomman Posted May 11, 2013 Share Posted May 11, 2013 (edited) I've rather easily built nasa-style space shuttles in the past (though I did cheat a little by putting ullage engines on the other side to keep it from flipping when the SRBs come off). I think what you could be doing wrong is putting an engine on the bottom of the big orange tank. That tank fuels the shuttle. Not it's own engine.I would get a picture of mine, but I don't have or the .craft anymore. Edited May 11, 2013 by mushroomman Link to comment Share on other sites More sharing options...
CalculusWarrior Posted May 11, 2013 Share Posted May 11, 2013 (edited) The main problem with NASA shuttles is that the centre of thrust does not go through the centre of mass. You have a massive shuttle perched on the side of a rocket. Also, I believe that the lift from your wings is causing some of that problem, creating a torque about the CoM.Some space shuttle mods either use massively gimballing engines (out unless you want to create a new part or use those mods), or else point the engines away from the External Tank & SRB's (what I would suggest). Edit: This is what I mean:If you're going for a straight up NASA launch, I would suggest following mushroomman's suggestion; omit the central engine.Another question, have you tried launching the shuttle with cargo? How much does it tip then? Edited May 18, 2013 by CalculusWarrior Link to comment Share on other sites More sharing options...
SecondGuessing Posted May 11, 2013 Share Posted May 11, 2013 Whenever I do a radially mounted space-plane I always just add the weight of the plane to the other side of the main tank using fuel tanks. It's not often pretty, but it works. Link to comment Share on other sites More sharing options...
Supernovy Posted May 11, 2013 Share Posted May 11, 2013 I usually do a similar thing by using an even number of EFTs. It doesn't count as NASA configuration any more, but it stops the CoM imbalance completely.It should be noted that the Energia used its own engines to propel the Buran, although I suppose that isn't NASA configuration either. Link to comment Share on other sites More sharing options...
Tw1 Posted May 11, 2013 Share Posted May 11, 2013 (edited) The only shuttle like thing I've made uses a pair of tanks, one on each side, perpendicular to the wings.It still turns a bit, but it's controllable, and it's just due to small problems with the orbiter design that need ironing out.I'm uncertain of the benefits of th NASA shuttle design, it seems strange to waste some thrust steering like that. Unless someone can explain why they decided to make it work as it did? Edited May 11, 2013 by Tw1 Link to comment Share on other sites More sharing options...
Shuttle Posted May 11, 2013 Share Posted May 11, 2013 Yes, one guy created a NASA-style shuttle. And I created Buran-style shuttle without any additional engines/RCS for stabilization http://kerbalspaceprogram.com/stock-space-shuttle/ Link to comment Share on other sites More sharing options...
Fel Posted May 11, 2013 Share Posted May 11, 2013 (edited) Maybe actually BUILDING it "In NASA Configuration" would help. [i mean, this WAS the most complicated build NASA did... so following specifications should yield far better results](TWRs are also much higher than they should be, especially at second stage (should be around 0.8)... and I still am wondering if you should be throttling the liquid engine that high during launch or saving most of that for second stage. [which would help persevere balance])Additionally, you need control surfaces on the Shuttle, to lean the rocket back rather than gimbal it around. (And the SRBs should be gimbaled which AGAIN hurts launch)*Point is to look up the specs rather than 'building it by your gut.'... although I do need to check it... I still feel that the main engines shouldn't come strongly into play until you breach the lower atmosphere (solving most of the "tipping" problems) Edited May 11, 2013 by Fel Link to comment Share on other sites More sharing options...
Frederf Posted May 11, 2013 Share Posted May 11, 2013 Definitely look to the FAR mod. It makes a lot of adjustments to aerodynamics and allows much tweaking of control surfaces. Link to comment Share on other sites More sharing options...
Deaf3279 Posted May 11, 2013 Share Posted May 11, 2013 They look cool, but I have mod that I download other day. I don't remember where it come from. Hope you dont mind I post 8 picture... why there's no picture of land? .... I crashed :-p I sucks with landing plane. Link to comment Share on other sites More sharing options...
Netris Posted May 11, 2013 Share Posted May 11, 2013 Try using Damned Robotics. Put a powered hinge with you engines on it and use it to gimbal them. That way, you could move the CoT to the right direction.EDIT : Deaf, it's Tyberdine Aerospace ^^ Link to comment Share on other sites More sharing options...
White Owl Posted May 11, 2013 Share Posted May 11, 2013 Try using Damned Robotics. Put a powered hinge with you engines on it and use it to gimbal them. That way, you could move the CoT to the right direction.EDIT : Deaf, it's Tyberdine Aerospace ^^You beat me to it! LOLI've been successfully launching space shuttles for months, using the method Netris describes. It takes some practice to learn how to manually gimbal engines while flying the ship, but it works very well. Link to comment Share on other sites More sharing options...
SkyHook Posted May 11, 2013 Author Share Posted May 11, 2013 You beat me to it! LOLI've been successfully launching space shuttles for months, using the method Netris describes. It takes some practice to learn how to manually gimbal engines while flying the ship, but it works very well.The great owl offers his advice! I am an avid fan of your videos, so I know of the method, but wanted to use a more elegant option, but you can't argue with what works. Downloading now! I will post in the forum when/if I have success. Link to comment Share on other sites More sharing options...
AncientAstronaut Posted May 11, 2013 Share Posted May 11, 2013 Yeah I don't know what to do either. I have been trying to build a space shuttle in KSP but even when I make sure the center of thrust is going directly through the center of mass, it doesn't seem to work. Link to comment Share on other sites More sharing options...
Netris Posted May 11, 2013 Share Posted May 11, 2013 You beat me to it! LOLI've been successfully launching space shuttles for months, using the method Netris describes. It takes some practice to learn how to manually gimbal engines while flying the ship, but it works very well.In fact, you've teached me everything I know on assymetrical thrust ^^ And one of my 2 shuttles in devellopement in inspired by you Eagle Link to comment Share on other sites More sharing options...
Challenger-X2 Posted May 11, 2013 Share Posted May 11, 2013 That's a good idea... I've been trying to build a shuttle to bring supplies to my space station but I have yet to build one that doesn't flip over immediately after launch. Link to comment Share on other sites More sharing options...
SkyHook Posted May 14, 2013 Author Share Posted May 14, 2013 Guys! Success! 100x100 Orbit Achieved..now to triple that Uploaded with ImageShack.us Link to comment Share on other sites More sharing options...
AngelLestat Posted May 14, 2013 Share Posted May 14, 2013 In the front view seems like a whale XDCongrats skyhook.I wanna to do a thread to talk all about shuttles, reusable ships to carry crew and cargo, with different approaches in the design. can we use this thread? or I make another one?Maybe a new one with a more general tittle will be better. Link to comment Share on other sites More sharing options...
SkyHook Posted May 14, 2013 Author Share Posted May 14, 2013 (edited) In the front view seems like a whale XDCongrats skyhook.I wanna to do a thread to talk all about shuttles, reusable ships to carry crew and cargo, with different approaches in the design. can we use this thread? or I make another one?Maybe a new one with a more general tittle will be better.You have my permission to use this thread to continue, I will see about changing the title to suit things better. Cheers! Edited May 14, 2013 by SkyHook Link to comment Share on other sites More sharing options...
paleorob Posted May 14, 2013 Share Posted May 14, 2013 I would love to be able to do a "real" shuttle without a tank booster or odd horizontal engine somewhere. Most of my shuttle-like spaceplanes end up center-stack lifted on a traditional rocket (like the DreamChaser/DynaSoar). Link to comment Share on other sites More sharing options...
White Owl Posted May 14, 2013 Share Posted May 14, 2013 I think this is the third or fourth time I've posted this in various places...Get the Damned Robotics mod. Attach a powered hinge or rotatron where you want the engine to go, set up two keys to rotate it (I use 7 and 8, but I have a really weird keyboard, so you might want something else), attach the engine. It takes some practice to manually control the gimbal through launch, but I think the added flexibility in building assymetric launch vehicles is worth it.IMO, the stock hinge and rotatron are too fast for this job. I edited mine to make them turn significantly slower, like so:// toggle parametersrotateJoint = TruerotateAxis = 1, 0, 0keyRotateSpeed = 6.0rotateLimits = TruerotateMin = -60.0rotateMax = 60.0rotateLimitsRevertKey = FalsejointSpring = 0jointDamping = 0onActivate = FalserotateKey = uprevRotateKey = downfixedMesh = BaseservoName = New HingeHell, I'll just go ahead and post a link to my whole channel, since this kind of launch vehicle is what I use almost exclusively nowadays: http://www.youtube.com/user/TheWinterOwlReally, I kind of feel bad that this technique isn't more well known. I've been showing people exactly how to make it work for months. Link to comment Share on other sites More sharing options...
bs1110101 Posted May 14, 2013 Share Posted May 14, 2013 I used damned robotics before, it works, but it's really hard to fly, it's much easyer to just add the tiberdyne shuttle plugin to the engines you want to use. Link to comment Share on other sites More sharing options...
White Owl Posted May 14, 2013 Share Posted May 14, 2013 I was told that plugin only works for one engine at a time. Is that correct? Has it been fixed, maybe? Link to comment Share on other sites More sharing options...
SkyHook Posted May 14, 2013 Author Share Posted May 14, 2013 I was told that plugin only works for one engine at a time. Is that correct? Has it been fixed, maybe?I would love to know this. Damned robotics got me into orbit, but if a plugin could handle the gimbal for me, that would be awesome. Link to comment Share on other sites More sharing options...
White Owl Posted May 14, 2013 Share Posted May 14, 2013 I would love to know this. Damned robotics got me into orbit, but if a plugin could handle the gimbal for me, that would be awesome.Same here. The hinges are good... but they're also prone to glitches and bugs at unexpected moments. Link to comment Share on other sites More sharing options...
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