Making big crafts maneuverable

[kiwiak]

How to make big crafts maneuverable and relavly easy to dock?

ANy tips on RCS placement? If i have RCS are reaction wheels still important? If yes, where do i place them?

Today i tried to dock 100 tonn module to my space station core, and... failed.

[KvickFlygarn87]

Place RCS as far from CoM as possible.

Reaction wheels are still good, and most crafts can do with 3 tops.

[Tank Buddy]

Reaction wheels help, but at a certain point you need a ridiculous amount of them to make a large ship very responsive. This mod: http://kerbalspaceprogram.com/rcs-build-aid-v0-2/ helps you balance RCS so you don't rotate while translating. I believe RCS is more effective the further from the center of mass, whereas SAS torque works better when in the center of a ship.

[relin]

Place RCS as far from CoM as possible.

That's the main idea. Placing them near the CoG will limit how much moment the give the craft, so put them near the extremities.

[Markus Reese]

For maneuverability, I guess it does depend on where you place them. It kinda makes me think though about something I never checked. Can you set toggle RCS? For large dockings, I place them close to center of gravity on either side to prevent spinning making it all translation movements and to minimize spinning. Long distance flight crafts, I will use structure to apply rotation torque which is what I want and not translation. I will need to try later, and if not, definitely going to add toggle abilities to my RCS so I can set up hotkeys. I usually have my thrusts and mass well balanced but I still hate translating with the rocket starting turning every time I try.

[JayKay]

I built a 900 tonne plus ship in my previous sandbox save. I had five central ASAS units and nine more reaction wheels by the Nervas at the back. It could quickly and precisely maneuver to any orientation I wanted (well, other than the horrendous lag slowing things down.) So, it is certainly possible to make a big ship maneuver using ASAS units. It won't help you dock, though, since you need RCS to do linear movements.

I used to regularly dock fuel ships to my space station at about 80 tonnes each. The best advice I can give is make sure your RCS units are positioned at the axes of the center of mass, and that you have four of them, symmetrically placed front and back and on both sides. This is more important than being at the corners of the ship. Sometimes it helps to move fuel back and forth between different tanks to help balance the ship. It's still important to have one or two heavy duty reaction wheels working to help keep the ship in line if it's slightly off balance. By switching back and forth between linear and rotation mode quickly you can also keep even badly balanced craft lined up, but it takes some practice.

JK

[Vanamonde]

A big ship is not going to be very maneuverable no matter what you do with it. The trick is to be patient and move it slowly.

[Blue]

A big ship is not going to be very maneuverable no matter what you do with it. The trick is to be patient and move it slowly.

And if you're handling it so it faces situations where it needs to be more manoeuvrable, then you're managing your maneuvers wrong and should slow down.

Almost all my spacecraft are handled just find with only 8 RCS Blocks-- placing them with 4-symmetry at the farthest ends of the spacecraft, "top" and "bottom".

[Taki117]

Might I recommend This Mod to help with RCS placement.

[Scarecrow88]

I generally only use RCS for translational movement, in which case it can be placed anywhere on the craft, but needs to be balanced to prevent any secondary effect rotation. However if you want to use it for rotational movement, moving it as far from the CoM will give the greatest leverage and most movement for any given use. Conversely reaction wheels will work best when placed as close to the CoM as possible as it will balance the mass they are trying to spin.

[kiwiak]

Are 7-point rcs thrusters worth using?

[Skorpychan]

My big multi-part ships have a reaction wheel or two on each section, and RCS at CoM for smaller bits, and at each end of larger ones. So far, it seems to dock pretty well, and they spin around fairly easily IF I'M CAREFUL on reaction wheel force alone. Unfortunately, I didn't get to check the maneuverability of extremely large things, because the kraken ATE my Duna mission.