Fairings with stock aerodynamics

[Jofe]

I was wondering if there's any usefulness with using fairings on the stock aerodynamics, beyond making cool looking rockets. I unlocked them but didn't use them for a while because the contracts I was getting could be easily completed by designs I already had just by adding a little something else depending on the contract. When I finally got to make a new rocket I decided to add a fairing and noticed I was losing around 800 m/s of delta V. So I was wondering if I was better off not having them and it was better just to have those 800 m/s. So considering what I was losing, is it really worth it to use them? Will the reduced drag compensate for the amount of delta V lost? Is there anything that I'm not taking in consideration?

[Frybert]

I personally have had nothing but problems using the stock fairings in since 1.05.

[FullMetalMachinist]

My experience with fairings has been that they're only useful for extremely draggy payloads, for the very reason that you mentioned. They add quite a bit of weight, but really don't cut down on drag that much, so they only help on a few edge cases where the payload is so draggy that it makes your rocket flip-happy. 

It's also worth noting that IRL fairings are more for protecting the payload. Streamlining the rocket is a secondary consideration. 

Edited January 25, 2016 by FullMetalMachinist

[FancyMouse]

Yup the more important part is to protect delicate stuff inside. For example with RT, most antennas snap under high dynamic pressure when deployed. This can be well shielded by a fairing and I now seldom use one extra antenna just for launch. Other case may include putting a heat shield on the top and you don't want to consume ablator during launch.

1.0.5 drag bug on the fairing is just a stupid regression - since we have a community fix in stock bugfix mod, just install that and forget about it.

[Streetwind]

What kind of rocket loses 800 m/s dV to a fairing?! o.O From my experience the cost is closer to 80, if that high.

I mean, you're supposed to stage the fairing away by the time you're three quarters to orbit, which is around 2400 m/s dV. So you're essentially saying that you are losing a full third of your dV. The fairing required to add that much mass should be larger than your entire rocket.

[Wemb]

I asked a similar question recently - it looks like they're somewhat broken in the stock game and will probably make your rockets considerably harder to fly, and, consequently potentially less effecient as you may need more care/equipment needed to keep them on course.  I've given up on them at the moment. Not sure if putting a big nose cone at the front of a rocket with a separator provides any protection to the parts underneath it or not (I don't deploy my antenna in the atmosphere), but it's aesthetically pleasing.

 

Wemb

[Crzyrndm]

You'd be better off with a nosecone sized to w/e the final attach node is. A larger cone is harmful in stock (larger front face, only partial occlusion of the back face. Doesn't care about any radial parts ever), and under most circumstances is harmful in FAR as well (same reasons, except it actually cares about everything).

Edited January 26, 2016 by Crzyrndm

[Tex_NL]

46 minutes ago, Wemb said:

I asked a similar question recently - it looks like they're somewhat broken in the stock game and will probably make your rockets considerably harder to fly, and, consequently potentially less effecient as you may need more care/equipment needed to keep them on course.  I've given up on them at the moment. Not sure if putting a big nose cone at the front of a rocket with a separator provides any protection to the parts underneath it or not (I don't deploy my antenna in the atmosphere), but it's aesthetically pleasing.

 

Wemb

And as it has been said in nearly every other thread the body lift vector on the fairings is placed too far forward. Claw's StockBugFix puts it back where it belongs.

[MagicFireCaster]

I use them a lot when i get rovers or delicate parts to orbit (i don't like slow rockets), other than that you could just go without them

[Jofe]

On 1/26/2016 at 3:28 AM, Streetwind said:

What kind of rocket loses 800 m/s dV to a fairing?! o.O From my experience the cost is closer to 80, if that high.

I mean, you're supposed to stage the fairing away by the time you're three quarters to orbit, which is around 2400 m/s dV. So you're essentially saying that you are losing a full third of your dV. The fairing required to add that much mass should be larger than your entire rocket.

I'm going  by what Kerbal Engineer tells me. I don't have the exact rocket anymore but from what I remember it was very close to this.

And after fairings while I didn't lose around 800 m/s dV this time, I lost around 650

Edited January 27, 2016 by Jofe

[FancyMouse]

11 hours ago, Jofe said:

I'm going  by what Kerbal Engineer tells me. I don't have the exact rocket anymore but from what I remember it was very close to this.

KER has a bug (or more precisely, a workaround for 1.0.4 stock bug that no longer applies for 1.0.5 because stock bug fixed) that double-counts the fairing mass. I've reported in KER thread but seems it got buried.

[Starhawk]

20 hours ago, Jofe said:

I'm going  by what Kerbal Engineer tells me. I don't have the exact rocket anymore but from what I remember it was very close to this.

And after fairings while I didn't lose around 800 m/s dV this time, I lost around 650.

It looks to me as though your fairing isn't nearly pointy enough.

Happy landings!