Now that we have stock fairings...

[Sokar408]

.. Is there any reason at all to use Procedural Fairings mod? The only functional advantage I see, is that PF has auto struting, which is great, but is there a functional difference between stock and PF fairings in their basic function, that is to shield stuff and reduce drag?

[Eric S]

Procedural Fairings have a few other advantages that I'm aware of:

No size limit (you can have a size limit, I think, but it isn't required)

Clamshell-style fairing separation, rather than the confetti separation that stock fairings currently use (hopefully we'll get an option to use clamshell fairing separation in 1.1, and possibly other settings)

Rounded fairings as an option as opposed to just pointy fairings

[peachoftree]

I also like how it determines the shape for you, I find making stock fairings to be quite tedious, especially bigger ones.

Also there's this:

[Requia]

How is mass of bigger procedural fairings? I've run into issues with stock where fairings are >30 tons for a 50 ton payload.

[sal_vager]

How is mass of bigger procedural fairings? I've run into issues with stock where fairings are >30 tons for a 50 ton payload.

Red Iron Crown and myself calculated that the fairing panels alone are equivalent to 14.4mm thick aluminium sheet, Kerbals are serious about protecting their payloads (and it explains why fairings are such good heat shields).

[Idrryl]

The thing I don't like about PF is that it looks ugly compared to stock so I avoid using them. Stock's fine for me, never ran into any trouble with the confetti explosions.

[Chaos_Klaus]

Well, I too think that tha fairings in stock are too heavy. Most of the time bringing a fairing doesn't give you an advantage over launching a naked payload due to the added mass.

Someone on reddit tested the best altitudes to jettison the stock fairings. It was around 20km already. If you bring them all the way to suborbital, they have don't save you any delta v.

[Requia]

Red Iron Crown and myself calculated that the fairing panels alone are equivalent to 14.4mm thick aluminium sheet, Kerbals are serious about protecting their payloads (and it explains why fairings are such good heat shields).

I may need to do one of those battlecraft mockups using fairings as ablative armor.

[Sokar408]

Well, I too think that tha fairings in stock are too heavy. Most of the time bringing a fairing doesn't give you an advantage over launching a naked payload due to the added mass.

Someone on reddit tested the best altitudes to jettison the stock fairings. It was around 20km already. If you bring them all the way to suborbital, they have don't save you any delta v.

My understanding was, form old FAR, that fairings was there to allow you to actually get to orbit. In old FAR, getting a lot of designs in space without a fairing was nearly impossible. As for the weight, isn't that as the devs intended?

[Soda Popinski]

I understand the stock fairings are physicsless parts. So when you jettison them, you keep the fairing mass. Not the same with PF. Plus the stock fairings disappear after jettison, unlike PF.

I'm playing stock right now with the 1.0 release, but may go back for a few mods.

[Sokar408]

I understand the stock fairings are physicsless parts. So when you jettison them, you keep the fairing mass. Not the same with PF. Plus the stock fairings disappear after jettison, unlike PF.

I'm playing stock right now with the 1.0 release, but may go back for a few mods.

That sounds completely out there if true.

[Red Iron Crown]

I understand the stock fairings are physicsless parts. So when you jettison them, you keep the fairing mass. Not the same with PF. Plus the stock fairings disappear after jettison, unlike PF.

I'm playing stock right now with the 1.0 release, but may go back for a few mods.

The mass part is no longer accurate. Fairing parts are massful (as are all physicsless parts now), their mass is added to the base and the CoM of the base is offset as appropriate, then when ejected that mass is removed.

I consider the parts disappearing a feature, having fairing debris would just be tedious for little benefit.

[Soda Popinski]

The mass part is no longer accurate. Fairing parts are massful (as are all physicsless parts now), their mass is added to the base and the CoM of the base is offset as appropriate, then when ejected that mass is removed.

I consider the parts disappearing a feature, having fairing debris would just be tedious for little benefit.

Did that change from 1.0? Maybe I just misread something.

If fairing mass is significant and set to the base, that can give an unrealistic CoM. You typically want as much mass up front.

[Red Iron Crown]

Did that change from 1.0? Maybe I just misread something.

If fairing mass is significant and set to the base, that can give an unrealistic CoM. You typically want as much mass up front.

It arrived in 1.0.1 IIRC, and the CoM of the assembly is offset upwards to account for where the combined panels+base CoM should be, as I mentioned.

[Soda Popinski]

It arrived in 1.0.1 IIRC, and the CoM of the assembly is offset upwards to account for where the combined panels+base CoM should be, as I mentioned.

Cool. Probably just stick with stock for now myself.

[Red Iron Crown]

It arrived in 1.0.1 IIRC, and the CoM of the assembly is offset upwards to account for where the combined panels+base CoM should be, as I mentioned.

I have to correct myself after testing this, it appears the mass of the panels is added to the fairing base but that the CoM is not offset.

[Captain Sierra]

I consider the parts disappearing a feature, having fairing debris would just be tedious for little benefit.

Are you dropping your fairings after circularization? The fairing shells should go suborbital and burn up on the way back down.

[Red Iron Crown]

Are you dropping your fairings after circularization? The fairing shells should go suborbital and burn up on the way back down.

I drop them before circularization during ascent, but that's not the only use case for fairings. Having the useless debris automatically removed is a feature, IMO.

Also, sometimes I forget to stage them before circularizing.

[Soda Popinski]

I have to correct myself after testing this, it appears the mass of the panels is added to the fairing base but that the CoM is not offset.

The main question is, does the mass of the craft get reduced after fairings are jettisoned?

[Murph]

The main question is, does the mass of the craft get reduced after fairings are jettisoned?

According to both KER and MechJeb, the mass is reduced when the fairing is jettisoned.

- - - Updated - - -

In the interests of science, I just did a simple experiment to confirm it.

1.25m fairing base with large fairing

OCTO2

Oscar-B

48-7S

Thrust limiter adjusted to give 0.5 TWR with the fairing, 1.3 TWR without it (but base still in attached). Launch, full throttle, stage the engine. Stuck firmly to the pad, not a hint of rising. Jettison fairing, and we have lift off.