Attaching lander to side of mothership and keeping weight ballance

[kiwiak]

I dont want to attach lander in front of the ship. I cant attach it to the bottom (next to engines). So i have to attach it to side.

But i need to keep weight ballance to have controllable ship during burns.

Possible solutions i came up with:

- Using two twin landers attached to both sides of ship

- Attach droptank to other side of ship and after detaching lander pump fuel from drop tank and detach it too.

- Some very high gimbal engine?

- Move engine around using some servos from infernal robotics.

- Use multiple engines on mothership and adjust thrust using throttle controlled avionics mod to keep facing forward

[Pecan]

You can tweak the thrust in the VAB so you don't (necessarily) need a mod for that, otherwise I think you've covered all the options.

[Claw]

I see that this is already "Answered," but for sake of completeness (and if anyone else looks here for info)...

If you're using v0.23.5, ladders are now insignificant to the physics engine. So while the VAB may show that the CoM moves when you put the ladder on, it won't actually effect your CoM in flight. This can also be a problem as it make it difficult to line up Center of Thrust and Lift on a Center of Mass that isn't telling the truth.

You used to have to add ladders on opposing sides, or other utility things. But not anymore.

See these two threads for a list of physics insignificant parts (and discussion).

http://forum.kerbalspaceprogram.com/threads/75951-PhysicsSignificance-related-problems

http://forum.kerbalspaceprogram.com/threads/76173-Massless-parts

Cheers

[kiwiak]

I see that this is already "Answered," but for sake of completeness (and if anyone else looks here for info)...

If you're using v0.23.5, ladders are now insignificant to the physics engine. So while the VAB may show that the CoM moves when you put the ladder on, it won't actually effect your CoM in flight. This can also be a problem as it make it difficult to line up Center of Thrust and Lift on a Center of Mass that isn't telling the truth.

You used to have to add ladders on opposing sides, or other utility things. But not anymore.

See these two threads for a list of physics insignificant parts (and discussion).

http://forum.kerbalspaceprogram.com/threads/75951-PhysicsSignificance-related-problems

http://forum.kerbalspaceprogram.com/threads/76173-Massless-parts

Cheers

Actually i meant landers, not ladders

[cantab]

If you will only make major burns with the lander attached, angle your engines slightly so they point through the CoM of the whole combination.

If you're using multiple engines, you could probably keep balance with manual adjustment of the thrust limiters, since you only need to worry about two states: lander and no lander. You can adjust said limiters in-flight on liquid engines.

Whatever your solution, you'll make things easier the closer to the centreline you can get your lander. For example if most of your ship uses 2.5 m parts, consider putting a 1.25m tank in the stack and attaching the lander to that.

[Pecan]

I stick mine on a girder and then wrap fairings around the whole thing if possible.