How to make flaps for pure stock craft

[4472TJ]

Probably being really thick but, how is one to make flaps for an aircraft in stock KSP because I have no idea?

[Snark]

27 minutes ago, 4472TJ said:

Probably being really thick but, how is one to make flaps for an aircraft in stock KSP because I have no idea?

Control surfaces have an action called "deploy" that can be toggled on and off (either by a button in their right-click menu, or via action group).  When "deploy" is active, the control surface automatically moves to its maximum (positive) deflection possible, instead of being at its default "zeroed" position.

The control surface also has an option "Deploy Direction" which can be set to normal (the default) or "inverted", which you toggle on/off via a button in the right-click menu, either in the editor or in flight.  When "inverted" is turned on, then activating "deploy" causes it to go to its extreme negative position (i.e. the min instead of the max).

So, for example, suppose you've built an airplane, and it has some ailerons on the wings, and you'd like to be able to use those as "flaps".  So, here's how you could set that up in the vehicle editor:

1. Open the right-click menu and click "deploy", and see which direction they go.  Up, or down?
2. Presumably you want the flaps to go down, if they're on the wings, so they can give extra lift.  So, if you try the deploy button and they go down, great.  If they go up instead of down, just click the "invert" button to fix that.
3. Now that you've got them correctly configured for inverted-or-not, toggle deployment "off" again so they go back to the neutral position (assuming you want to launch your craft that way).
4. Let's say you want to be able to deploy/undeploy them via action group.  Go to the action-group pane, click on the aileron, and choose the "Toggle Deploy" action to assign to whatever action group you like.

There, that's it, you're done!    When flying, just press the appropriate action-group button to toggle your flaps on and off.

That's the simplest, most basic way to set them up.  There are some other options if you want to get fancy-- for example, if you want to have a control surface that only functions as flaps (and won't try to adjust pitch/roll/yaw), or if you want to have variable flaps instead of a simple on/off.  But that's the gist of it.

[4472TJ]

Thanks! Now to start work on a new top secret plane......