How to make vertical stabilisers and rudders.

[CaptainKipard]

If regular wings have a lift direction, then what's the proper work flow for vertical stabilisers?

[HoneyFox]

When wing is put at a position after the CoM, it will automatically provide pitch stabilization.

Reason simple: when under certain positive AOA, the lift generated by the wing will be higher than that when AOA is zero, since the lifting force is after the CoM, it will generate an additional pitch-down moment and the AOA will then tend to reduce. When negative AOA, the lift will be smaller or even negative, and will generate an additional pitch-up moment, change the pitch rate and finally AOA will increase.

[CaptainKipard]

Vertical Stabiliser, for the googly challenged

[Guest]

KSP wings have no lift direction. They're symmetrical airfoils (or rather, the simulation is too dumb to account for an airfoil type), the "lift vector" is removed from FAR for this reason. Generally, you just set up a regular wing and put it up vertically. Lift depends only on AoA.

[HoneyFox]

Vertical Stabiliser, for the googly challenged

Oops... you mean vertail...

Well just replace AOA with Sideslip angle in my previous post and pitch-down/up with yaw left/right and that's it.

[CaptainKipard]

What's this all about then?

[nli2work]

I imagine it'd be the same as a control surface. unless you're talking about a fin without a rudder... then it's probably just a normal wing piece, I'd copy the config from one of the SPP parts.

[Guest]

What's this all about then?

Well, obviously if the wing is wrongly oriented in general, it'll "think" it's facing the airflow straight on (like a big draggy board), while seeming to be attached properly.

[CaptainKipard]

... obviously...

Yes

Time for bed I think...

[CaptainKipard]

Back again. I tried to set it up like my wings, and it's making the plane veer wildly to one side. I know because taking it off makes the plane drive straight.

Also for some reason the rudder (obj_ctrlSrf) isn't rotating about its x axis, instead rotating about it's origin in the part x axis.

This is the last part left to be rigged in the Skylon mod. Let's make some progress.

PART
{

// --- general parameters ---
name = KipEngSkylonStabiliser
module = Part
author = Cpt. Kipard

// --- asset parameters ---
scale = 1.0
rescaleFactor = 1

MODEL
{
	model = KipEng/parts/SkylonC2/SkylonStabiliser
}

// --- editor parameters ---
TechRequired = advFlightControl
entryCost = 4600
cost = 600
category = Aero
subcategory = 0
title = Skylon Stabiliser
manufacturer = Kip. Engineering
description = Skylon Stabiliser

// --- node definitions ---
// attachment rules: stack, srfAttach, allowStack, allowSrfAttach, allowCollision
attachRules = 1,0,1,1,0

NODE
{
	name = vstabilisernode
	transform = n_vstabiliser
	size = 1
	method = FIXED_JOINT
}

// --- standard part parameters ---
mass = 0.6
dragModelType = override
maximum_drag = 0.02
minimum_drag = 0.02
angularDrag = 5
crashTolerance = 12
maxTemp = 3400
explosionPotential = 0.1


MODULE
{
	name = ModuleControlSurface
	dragCoeff = 0.6
	deflectionLiftCoeff = 0.4
	ctrlSurfaceRange = 15
	ctrlSurfaceArea = 0.2
}
}

Edited November 4, 2014 by Cpt. Kipard

[nli2work]

what orientation is the unity export? I'd set it up just like any other winglet part, leading edge +Y; axis of contro surface rotation on X

Edited November 5, 2014 by nli2work

[CaptainKipard]

Ok. I just realised that's what I did for my wings too. They are at an angle when attached but the part axis is aligned with the aileron axis.

That just leaves the mystery force.

Edit:

Problem solved. I was working on faulty information. The offending thread link has been removed from the dev links thread.

If anyone else is having problems follow the tutorial by Justin Kerbice. -Z for wings and control surfaces is Up in unity.

Edited November 14, 2014 by Cpt. Kipard