NASA-style space shuttle help

[TerrificToby]

Hello all. I have recently attempted at a shuttle design, and i had the problem that there was too much thrust coming from the SRBs strapped to the external tank and not enough from the shuttle itself. the result was my shuttle nose diving the ground. How do I get it to go straight up?

I have used the Tiberdyne space shuttle system and the MK3 parts expansion pack.

Edited May 29, 2013 by TerrificToby
additional info

[Pursuedtank]

NASA style shuttles are very difficult to do right. You will have to have the center of thrust going through the center of mass, so that you could draw a line along the thrust line and it would intersect the center of mass. This has to keep being adjusted all the way up as you burn through fuel. I managed it once with an incredably unstable craft. It is not an easy feat.

[TerrificToby]

how is it that i have seen videos where a premade tiberdyne shuttle goes up dead straight? is there some mod?

[Tex_NL]

Add/rotate engines in such a way your total thrust vector is in-line with the center of mass. Keep in mind that while you're using fuel from the tank your CoM shifts and once you drop the SRB's your CoM AND CoT change.

Engine gimbal in KSP is limited and throttle can't be set for individual engines making classic shuttle launches inherently difficult. Sandwiching your shuttle between two boosters or launching your shuttle Hermes style is much easier.

[TerrificToby]

update on my situation: i have managed a nasa style launcher, it all goes well until the gravity turn. then the craft goes into a unrecoverable spin. need help! i really want this to work.

[rodion_herrera]

Add/rotate engines in such a way your total thrust vector is in-line with the center of mass. Keep in mind that while you're using fuel from the tank your CoM shifts and once you drop the SRB's your CoM AND CoT change.

Engine gimbal in KSP is limited and throttle can't be set for individual engines making classic shuttle launches inherently difficult. Sandwiching your shuttle between two boosters or launching your shuttle Hermes style is much easier.

To compensate for the change of CoG, one can use the Rockomax 24-77's in strategic places, mostly near the top of the fuel tank, to force it to a particular angle, as fuel gets drained. I saw this done in a KSP shuttle video once, but I can't find it at the moment.

[Crush]

Wings on a vertically-launched vehicle are always problematic. The moment you aren't ascending perfectly vertical, they start to generate lift which results in rotation.

For that reason you should wait with your gravity turn until you are outside the atmosphere.

[rodion_herrera]

Wings on a vertically-launched vehicle are always problematic. The moment you aren't ascending perfectly vertical, they start to generate lift which results in rotation.

For that reason you should wait with your gravity turn until you are outside the atmosphere.

There is a very simple solution to the problem of wings generating lift in KSP--mount control surfaces on radial decouplers, and these control surfaces must be aerodynamically positioned (via SHIFT-WASD) so that they create a DOWNWARD FORCE instead of lift)...and when preparing for re-entry, simply jettison these "Pusher" control surfaces away, and voila, your shuttle should now "normally" fly once it encounters enough air density in Kerbin's atmosphere.

[zanzibar196]

Can't be done using standard KSP parts, due to the fact of how lift works in the game, coupled with the fact there are no engines that gimbal enough... Hopefully they add some things that make a shuttle style craft possible!

[TerrificToby]

There is a very simple solution to the problem of wings generating lift in KSP--mount control surfaces on radial decouplers, and these control surfaces must be aerodynamically positioned (via SHIFT-WASD) so that they create a DOWNWARD FORCE instead of lift)...and when preparing for re-entry, simply jettison these "Pusher" control surfaces away, and voila, your shuttle should now "normally" fly once it encounters enough air density in Kerbin's atmosphere.

so they'll be like the wing extensions of a commercial airliner?

[boogman]

Hey bud, it's quite simple, I have a working shuttle , it can reach orbit with 3k deltaV spare and has an easily modifyable fuselage length

I edited 1 value to allow the ssme's to more accurately reflect the vectoring from the real shuttles.

If you would like I'll be more than happy to make a vid of sts1 to demonstrate its basic functions and then follow by release of the model

Lemme know if your interested

[Vanamonde]

That is kind of you, boogman, but since this thread is nearly 2 years old, OP has probably moved on.