Force fairings to be larger

[vitekc45c]

Is there any way to force fairings to be larger in diameter? Say I take 3.75 one, extend it out as far as I can and save the craft in editor, what values in the craft file would I need to edit to up the fairing diameter to.... say 20 meters?

Edited July 9, 2018 by vitekc45c

[Snark]

34 minutes ago, vitekc45c said:

Is there any way to force fairings to be larger in diameter? Say I take 3.75 one, extend it out as far as I can and save the craft in editor, what values in the craft file would I need to edit to up the fairing diameter to.... say 20 meters?

It's not a property of the craft-- it's a property of the part.  Therefore, enabling this is not something you do by tinkering with the craft file.  Instead, you'll  need to patch the part config for the 3.75m fairing so that it lets you do what you want it to do.

If you look at the 3.75m fairing's config file, you'll see that its ModuleProceduralFairing entry has a line maxRadius = 6.  I presume that that's what sets the value of "what's the biggest radius possible for this fairing". So, I'm guessing that if you boost that value, it'll allow setting a bigger radius.  Probably the simplest way to do this would be with a ModuleManager patch, thus:

1. Make sure ModuleManager is installed.
   • If you've got many mods at all installed, there's a good chance that you've got it already.
   • If perchance you don't, you can get it from here.
2. Create a new file somewhere in your GameData folder, whose name ends in ".cfg".  (Can name it whatever you like, and it can go wherever-- either directly in GameData, or in a subfolder thereof.)
3. Paste the following content into that .cfg file you just created:

@PART[fairingSize3]
{
    @MODULE[ModuleProceduralFairing]
    {
        @maxRadius = 20
    }
}

...I think that ought to do the trick.  Once you've got the file in place, start up KSP.  Hopefully, that part will now allow you to go up to the desired radius.

(Haven't tested this myself.  But I'm guessing that this will do what you want.)

[Gargamel]

Making it bigger in the VAB, and aerodynamically stable.... two greatly different things.....   Don't think I've ever seen the airliner wings used as tail fins, but I may shortly. 

[vitekc45c]

Thanks, now I just need a bigger SPH

[DunnoAnyThing]

1 hour ago, vitekc45c said:

Thanks, now I just need a bigger SPH

Hanger Extender mod maybe?

 

[StrandedonEarth]

On 7/9/2018 at 5:57 PM, Gargamel said:

Making it bigger in the VAB, and aerodynamically stable.... two greatly different things.....   Don't think I've ever seen the airliner wings used as tail fins, but I may shortly. 

I haven't had to go that far, but I used Shuttle tailfins to get this station core into orbit...

[Gargamel]

1 hour ago, StrandedonEarth said:

I haven't had to go that far, but I used Shuttle tailfins to get this station core into orbit...

Well.... I bet it would fly much better if you lost the asteroids..... or added a fourth...

[StrandedonEarth]

5 hours ago, Gargamel said:

Well.... I bet it would fly much better if you lost the asteroids..... or added a fourth...

Well, I couldn't find a pic of just the core. The 'roid arms were added in orbit. The problem was the six-way 2.5m docking hub at the top. A 20m fairing could have helped with that, instead I had to brute-force it.

[swjr-swis]

On 7/10/2018 at 2:57 AM, Gargamel said:

Making it bigger in the VAB, and aerodynamically stable.... two greatly different things.....   Don't think I've ever seen the airliner wings used as tail fins, but I may shortly. 

Well... you have now.

Spoiler

Looks like someone got parts mixed up.

It does take off without incidents.

Full stick maneuvre, we keep flying.

Runway approach is not a problem.

Safely landed too.

Full imgur album: https://imgur.com/a/OEaCRFo

Craft file: https://kerbalx.com/swjr-swis/McTailfins

[swjr-swis]

On 7/9/2018 at 8:41 PM, vitekc45c said:

what values in the craft file would I need to edit to up the fairing diameter to.... say 20 meters?

On 7/9/2018 at 9:14 PM, Snark said:

enabling this is not something you do by tinkering with the craft file.

Actually, it can be done in the craft file too, if you just want to make this change once for that one craft.

 

Search for the following in the craft file:

		XSECTION
		{
			h = 0
			r = 0.625
		}
		XSECTION
		{
			h = 0.598072052
			r = 0.625
		}
		XSECTION
		{
			h = 1.24200153
			r = 0.523973823
		}

The fairing part in the craft file will have an 'XSECTION' per (height) segment of the fairing. h is the start of the segment counting from the top of the fairing base, and r is the radius, both in meters. The first XSECTION is effectively where the fairing touches the base, and should always retain the standard values.

Keep in mind that the fairing code will try to 'soften' abrupt changes in diameter, which may cause some of the segment edges to be wider/narrower than the exact number chosen.

Edited July 11, 2018 by swjr-swis
Why did my 'edit' of the first post save as a separate message?

[Gargamel]

9 hours ago, swjr-swis said:

Well... you have now.

Meh.... the planes just compensating for something there.... 

Nah.... I'm talking a rocket, with a 20m fairing, 100m tall, with an itty bitty 5m launcher, with these huggggge fin to keep it stable. 

[bewing]

2 hours ago, Gargamel said:

I'm talking a rocket, with a 20m fairing, 100m tall, with an itty bitty 5m launcher, with these huggggge fin to keep it stable.

I don't think that would work. For passive stability (using fins), the drag in the back has to be bigger than the drag in the front. If the drag in the front is proportional to the square of the frontal area -- being a 20 meter circle -- you need something even bigger than that in the back.

I think the only way to launch such a thing would be to use a puller-configuration. Engines in front, stack of fuel tanks, big fat fairing at the bottom.

 

[Superfluous J]

On 7/9/2018 at 11:24 PM, vitekc45c said:

 

21 hours ago, StrandedonEarth said:

Seeing these two images in quick succession in a thread about making fairings larger made my lizard brain think I was seeing fairings so big you can see them from space.