'adjusting the trim'... what is it, and how do I do this?

[kahlzun]

In many of the KSP videos on Youtube, especially ones with spaceplanes, they mention 'adjusting the trim'.

What does this actually do, and how does one do it exactly?

[Synapse]

It moves the default position of your control surfaces

You hold alt and W/S/A/D

[El wonso]

Trimming adjusts not only cotrol surfaces but the whole steering.

[what-the]

Can also be used as cruise control on rovers. Press alt X to reset.

[Motokid600]

Ive never used it and still don't understand how it differs from the regular controls.

[Sean Mirrsen]

It's... well, it's trim. It's the same thing you use on every radio-controlled toy airplane ever, and on any decent joystick. It allows you to move the "center" of the controls, so that the "rest" position is actually a little off to the side and upward, for instance, to compensate for the model you're flying being off-balance.

[xclusiv8]

Ive never used it and still don't understand how it differs from the regular controls.

Unlike regular controls trim is not used to directly control the jet. It is instead used to compensate for any errors in flight. For example, imagine you damage your wing and the jet start turning slightly to the left. Once you trim the jet it will once again keep flying straight because the control surfaces have been set to bypass that previouse error and compensate for it.

[rpayne88]

IRL, trim allows the pilot to relieve pressure on the yoke or stick. It allows the pilot to place the plane at a particular attitude and have the plane remain in that attitude without any pilot intervention. It is almost a mechanical autopilot. It functions the same way in KSP and can offer even finer control over air/spacecraft.

[Fleb]

Press alt + the WASDQE keys(alt+x to reset), and watch the, pitch, roll and yaw display on the left. It moves your controls so they hold a set position. It's something present in most flight sim games. I mostly only need it to alter pitch trim(alt+W and S), to make a plane to stay level in flight.

[rgeber]

By the way. if you're on Linux, the alt key is not working. Use the right shift key. Took me a while to figure that one out. Now these contraptions can actually fly.

[arq]

Using alt+W/A/S/D/Q/E will change the 'center' of each control axis. For example, if you add a few clicks of alt+Q to a ship, it will roll all on its own without any control input. It is mostly useful for making aircraft fly straight in the pitch axis without control inputs (using alt+W/S), rather than pitching up or down naturally. However, if you have SAS enabled then trim doesn't really do much.

[Wanderfound]

And, as will inevitably happen:

When you get to space and find that your craft starts spinning whenever you disengage the SAS...cancel your trim with alt-X. Also worth checking when a satellite or space station contract is refusing to complete "for no reason".

[KatzOhki]

Turning the battleship!

[Zach Schultz]

Press alt+q or alt+e to roll, alt+w or alt+s to pitch, and alt+a or alt+d to yaw.

Compared to normal controls, where you must hold the key down, you can just press the trim control and it will stay that way until you press alt+x, to reset.

[James Kerman]

Welcome to the forum @Zach Schultz,

Even though this is an old thread that's really great advice. I would also like to add that anyone having issues with key mapping should start a new thread in the appropriate technical support subforum and include the native language of your keyboard. This thread is now locked.