What's wrong with this ships

[vtgbart]

Hi,

I have just spent couple of houors building thath ship on Kerbin's orbit - combined my lander and its deploing vessel to two space tugs ( I call them space taxis). One was mounted in front of the lander, the other behind. After long docking procedures I refuelled entire ship and tested it - teh objective was to get enough delta V to get to moho.

Unfortunately my ship started to revolve after i throttled it up. What did I do wrong? HELP ! I cant attach my save file, but If u want I can mail it to you.

[Vanamonde]

I can't see the details of your ship very clearly, but I have some suggestions/questions for you. Redesign the ship so that the LV-N engines are not the link between stages. The length of the engine seems to provide leverage for masses ahead of it to swing around and draw the ship off heading: far more so than with any other engine. Are only the rear set of engines firing at the time you're talking about? Engines to the front of the ship contribute little to stability. What kind of capsules/cores are you using for guidance? Do you have enough torque for the mass in question?

[Nimaci]

The game doesn't reverse controls for gimballed engines that are in front of the vessels centre of mass, try only using the rear engines.

[Galacticruler]

Also, be sure not to use ASAS if there is one on each vessel and RCS helps to dampen any velocity based swaying from the orbital path.

[msyblade]

First of all, Gorgeous build. That thing would stop my cpu in its tracks! I think the suggestions here are correct however. The engines facing different directions, and being able to gimbal is likely causing confusion in the controls.

[FlamedSteak]

It looks as though your fuel loads are unbalanced.

It's impossible to tell which tanks sit where, but there are some varying fuel loads which could account for a wayward centre of mass.

[mellojoe]

my initial thought was fuel balance. Right click through your fuel tanks and make sure you don't have a weird fuel line problem. I had a rocket that for whatever reason considered a random tank on a stack as debris and wasn't using the fuel out of it. All the other tanks worked, and they were all placed in 4x symmetry. But only that one tank was borked.

Check fuel balance. Transfer things around if necessary.

Also, you may have to use a combination of front engines AND rear engines to keep it from cartwheeling. If the front end is massive enough, inertia might play a factor. The back end getting pushed and the front end not wanting to move can cause a rotational element. Play around with using 2 or 4 of the front engines to help balance out the thrust.

Good luck.

[CCKinnison]

Not just front and rear engines... If you're using multiple "taxis", make sure you do "control from here" on the one that's facing FORWARD, after everything's docked. I get huge oscillations and destructive rotation when a core is trying to control a ship pointing the other way.