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Oysterbarron

Le shuttle Can you get this to work? (space plane with vertical rocket)

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Hi everyone Iv'e been working on this shuttle for a good 6-8 hours and i think it has huge potential Here's a video of it in action and you will see the problems i'm having with it. Do you recon you can fix it?

here's the download link video 1 version

http://www./?7an22ojnsleupza

I might add that this is a space plane so you will need to place it in the space plane save location. To edit it i suggest grabbing the cockpit and using the rotate keys to change the orientation. I have also found out that the liquid fuel boosters on the shuttle wont work like i hoped in space as the cease to work after first stage separation.

download link video 2 version

http://www./?5z7jn99j85g7do7

Edited by Oysterbarron

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Actually it doesn't really matter if you put it in the VAB or SPH or not.. All that determines is which building/editor you get, and where you launch from.. Pad or runway.. since this is built vertically, there'd be no harm in putting it in the VAB. I move .craft files back and forth regularly myself. Especially if it's something hybrid like this.. start in the SPH and build a workable decent flying space plane, then move the .craft to the VAB and start tacking on rocket parts for vertical launch.

Though.. to be honest.. i've never successfully managed a working 'shuttle like' launch vehicle. I had some success before putting the space plane as the last stage of a normal rocket though.

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the only way ive ever been able to get a shuttle to vertically launch is by changing the gimbal range on the engines to 10 or more, the actual shuttle has a gimbal range of 10.5

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His issue is shifting center of mass. As the main tanks empty, the center of mass shifts towards the space plane while the center of thrust remains the same. The result is the that big mainsail engine is thrusting off center and causes the thing to flip end over end.

A functioning spaceshuttle type design is VERY hard to accomplish with stock parts currently.

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Try taking off the boosters first, and external fuel tank. then, use the center of mass and center of thrust, and if its balenced right, they should be around the same for safe flight. if not, it will spin like that. Then add the boosters&fuel tank, and turn on the center of mass and thurst again. not the same? Thats why it crashes.

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Iv'e tried placing the 2 boosters in various locations and in most cases initial stablization is comprimised in most cases. Im pretty sure it's all about counterbalancing the craft out somehow. The SRB's arent active on initial launch they are part of the shuttle stage do they still effect the balance even when not activated? The fuel draining could be an issue I dont like the sound of that.

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The problem is, the SRBs. They are angled and is not designed to be placed under something (read its description).

Ugh. I didn't even notice the core of his spaceplane was 3 SRB's. Yeah that would be the problem. It's not shifting center of mass, it's changing center of thrust. When they run out, the center of thrust shifts and end over end it goes.

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That will probably get you in a circular orbit. You need to work on your launch though

You should try starting your gravity turn at 10000m instead of just burning straight up the whole way.

when you get to 10000m in altitude, roll your ship east along the 90 line to about a 45 degree angle. then switch to map mode. also click the ^ on the bottom to bring up the navball, so you can keep an eye on and adjust your orientation without having to physically watch your ship. You need to do this so you can watch what altitude your apoapsis is at.. 70km is out of the atmosphere, so anything past that is ok. Since this ship appears to be marginal on it's orbit capabilities, You probably shouldn't shoot for much past 80km. When your apoapsis hits 80km, hit X to cut your engines, and coast the rest of the way till apoapsis.. since your ship has a lot of mass and no RCS, you'll probably want to pre-rotate to point towards the horizion on the 90 line on the navball, the rotation will probably take a while. Since the mainsail engine is gimballed, you can give it a little thrust to help turn faster, but remember your eating fuel when you do this,

When your roughly 20 seconds away from apoapsis and pointed towards the horizon on the 90 line on the navball, do a 100% burn, and hopefully you have enough fuel left to circularize your orbit.

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in all honesty, the real shuttle even keels over backwards... which is odd since all the weight should be going forward with the tank

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I've been using the following design

screenshot0_zps1b603207.png

But my attempts to launch it like a regular spaceshuttle keep failing so I put it on top of my rocket just like the ESA spacecraft Hermes would

screenshot1_zps674b9003.png

I even landed on Duna

screenshot7_zps95017954.png

I've been trying to get to Eve but keep failing at it.

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in all honesty, the real shuttle even keels over backwards... which is odd since all the weight should be going forward with the tank

The reason the real shuttle behaves like that is due to the shuttle engines having almost 11 degrees of gimbal. What it does is once it gets high enough in the atmosphere that drag is drastically reduced (accomplished with the SRB's), it can roll on it's back, and gimbal the engines outward, which keeps the center of thrust in line with the center of mass.

This is pretty much the key of how the shuttle gets into orbit with even with off-center thrust (which, the way it's done, isn't off center) and is something that's EXTREMELY hard to do in KSP.. It requires modifying engines to have a greatly increased gimbal range, and flying manually.

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First, put an ASAS module on the shuttle and the booster so the shuttle is easier to maneuver, and also duplicate the booster w/o the counterweight on the top side of the shuttle so even if the tanks go empty, the shuttle will still be balanced and you won't have to waste all that precious speed.

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I've been having problems getting into orbit using the following design

screenshot3_zps9b64a609.png

screenshot2_zps23160d09.png

screenshot1_zps9a931766.png

Any crash you can walk away from

screenshot4_zpsd0b3a4db.png

SO the problem is always the same as soon as the lift stages go I have to sacrifice, the belly tank (while far from depleted) or my craft goes into an uncontrollable cartwheel.

And their is insignificant fuel in the orbiter itself to get into an orbit.

Edited by Resender

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Try playing with fuel flow, get the side stages to drain last instead of first, then see if when you loose the middle engine you can remain stable with the outer two firing, not exremely efficient I know but. . . hey who cares?

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Ive tried a similar design just like your ship. the problems i ran into....

1. The center of mass requires a counter mass at the opposite side of your space shuttle.

2. The ships engine and the rocket it is attached too must run out of fuel at the same time.

3. doing the apogee burn (once u get into a orbit height e.g. 78km) causes it to flip over, requiring you to ditch the main stage.

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Taking that route kind of failed as well, with me having to glide the shuttle back from an altitude of 20km, and the shuttle itself having been at a 65% angle with the horizon.

But I soon got on the glide, using the fuel onboard untill that too depleted

screenshot5_zpse4ed9246.png

screenshot6_zpsb1086ecc.png

screenshot7_zps2867af8d.png

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you could have a wing jut out on the opposite side of the plane with nothing but weight, ie fuel. Would act as a counter balance and keep it even.

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